Amphibians and Reptiles
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Reptiles
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Ink turtle (Sepiochelys atramentophora)
Order: Turtles (Testudiniformes)
Family: Turtles (Emydidae)
Habitat: rivers and lakes of Central Africa.
Conservative and not too numerous group of turtles had suffered the big damage
as a result of human activity. Their largest species dwelt in islands had died
out the first. After them some endemic continental species which habitats were
destroyed by people had died out. The most mass species of sea and freshwater
turtles had suffered because of overhunt and unlimited egg gathering. In human
epoch areas of the majority of turtles had strongly reduced. Approach of the
ice age became one more impact to the variety of this order and besides appreciably
reduced the areas suitable for life of these reptiles.
In Neocene the warm climate had permitted to realize chance of a survival to
not numerous survived representatives of turtles. In various places of Earth
there were species adapted to
extreme conditions of inhabiting, or on the contrary,
prospering and dominant in favorable conditions. In some habitats turtles even
have turned to main predators of the ecosystem. But the majority of turtles
remained rather small animals, especially at the continents.
Presence of predators in the ecosystem stimulates the development of various
protective adaptations. In rivers of Central Africa the place of crocodiles
extinct till Holocene is occupied by the huge representative of Squamata order
– huge crocodile monitor lizard. This reptile hunts with the help of sight
and sense of smell, and force of its jaws permits this reptile to eat any animal
from ones living in rivers. One of turtles living in the neighbourhood of this
monster had developed the way to avoid the danger coming from the giant.
It is the aquatic turtle of rather usual appearance – it has flat carapace
of rounded outlines, webby paws and large head on mobile and strong neck. Usually
it slowly swims near the bottom, searching for forage: freshwater crabs, snails
and carrion. When the crocodile monitor lizard or predatory fish starts to
chase it, this turtle tries to rescue by flight. But, if the distance between
the turtle and its persecutor became critical, the reptile exposes “the second
line of defense”: it emits a cloud of black liquid from cloaca and receives
some seconds to hide. Hence the name of this reptile – it is ink turtle.
Ink turtle belongs to rather large species: carapace length of adult individual
is up to 60 cm at weight over 30 kg. The carapace of ink turtle is colored
olive with small black speckles. At old individuals it becomes covered by algal
layer, and even by aquatic moss. It serves as additional masking of the reptile.
Skin on legs, neck and head is brownish with set of light spots. On head of
animal spots merge to longitudinal strips, and the throat looks much more lighter,
rather than skin. Paws of the reptile have palamas between toes – ink turtle
swims very well, accelerating momentum under water up to 30 kms per hour. On
forepaws of males increased claws grow: they are very long (up to 5 cm), strong
and sharp. With their help males fight in courtship season. Claws also help
the male to be kept on the carapace of the female till the pairing.
The main weapon of ink turtle is the liquid of black color emitting out in
case of danger. In walls of cloacal bladders at this species numerous ink glands
accumulating pastelike black dye had appeared. When the turtle is in danger,
it squeezes out their secret to cloacal bladders where it mixs up with their
contents and is emitting in water as black liquid with unpleasant smell. Ink
of this turtle is a little bit similar by action to cephalopods ink: it has
poorly narcotic property, and may paralyse olfactory nerves of predator. It
has an action at reptiles in some minutes, but sense of smell of fish may be
paralysed till half an hour and more. Even the most young ink turtles having
length of carapace about 5 centimeters are able to emit ink.
Breeding at ink turtles lasts the year round. Courtship displays of these reptiles
are rather primitive: males try to banish each other from the female. The strongest
male, having got rid from contenders, starts to swim near the female, trying
to bite slightly its paw or neck. When the female shows the submission, stopping
attempts to departure, male couples to it and right after this act abandons
the female.
Eggs form in organism of the female till 25 – 30 days. For egg laying the reptile
leaves in wood, digs out the small hole in ground and lays simultaneously up
to 8 – 11 eggs. Having dug the nest, it is not interested in destiny of posterity
any more. The incubating lasts about 40 days. For one year the female can make
up to three clutches.
Algal
turtle (Thalassotestudo algophaga)
Order: Turtles (Testudines)
Family: Tortoises (Testudinidae)
Habitat: Tanganyika passage, coastal thickets of seaweed. Young growth lives
in estuaries of the rivers.
Before man began attack to nature, at sea meadows overgrown with seaweed
and sea grasses, large herbivorous water mammals – sirens (Sirenia) – grazed.
Unlimited
hunting has resulted to that dugong and manatees became very rare, and Steller’s
sea cow dwelt in Pacific Ocean had been exterminated at all. Ecological crisis
of the end of Holocene had resulted in extinction of the rests of sea herbivorous
animals. When balance in ecosystems of Earth was restored, seaweed and
sea flowering plants began to occupy much more extensive territories, than
in Holocene – they have taken place of productive communities earlier belonging
to coral reeves. In early Neocene at algal “pastures” only numerous shoals
of omnivorous fishes fed. But later new eaters, reptiles, huge algal turtles,
had added to them.
They are not descendants of sea turtles, existed millions years and suffered
from the human in Holocene, but completely independent group of reptiles.
They had descended from one of species of herbivorous tortoises, and the
combination
of unpretentiousness and diet has permitted them to gain sea meadows. Certainly,
many species of water turtles had gone through ecological crisis, but they
are predators and can not pass to vegetarian diet completely.
Algal turtle is rather large species of reptiles: the length of its carapace
reaches 1 meter. As at all turtles living in water, the carapace of algal
turtle has the streamline oval form. Head at this species is very big, with
strong
cutting jaws. In case of need this turtle can defend itself from any predator
by bites. Head does not retract under carapace, therefore additional protection
was developed on it: it is covered with special convex osseous scute. The
top part of carapace at algal turtle is colored light brown, but this colouring
can be invisible because of layer of the special microscopic algae settling
on carapace. When turtle creeps out on coast, algae cells form mucous membranes
protecting from drying in the sun, and due to what survive. Therefore carapaces
of turtles, as a rule, have more or less appreciable greenish shade. The
plastron
of turtle is colored yellowish-white. Skin on neck and basis of legs is grey-green,
on head and legs gray-brown. Males are larger than females, their plastron
in bend, as at all turtles; around of eye of the adult male the ring of large
thick scales of yellow color develops – it is a distinctive attribute of
the sexual matured male. Besides at males on forepaws the thick claws grow,
necessary
for female keeping at pairing.
Column-like legs of tortoises have turned at algal turtle to flat oar-like
flippers. This reptile perfectly swims and can dive for a long time, feeding
with underwater vegetation. But on land flipper-like paws are almost useless:
the turtle moves on sand hardly, dragging body like a seal. However it does
not create problems for turtle: this species of reptiles inhabits eastern
coast of Tanganyika passage belonging to Eastern - African subcontinent
(Zinj
Land) where large predators are not found. And against small and medium-sized
predators both in water and on land the algal turtle is reliably protected
with carapace.
The most important danger, with which the descendant of ground animals faces
passing to life in sea, is the danger of dehydration: concentration of salts
in sea water is more, than in blood of animals. The organism of ground turtles
is adapted to economical expenditure of internal stocks of water that had
permitted to ancestors of algal turtle to occupy sea. For more effective
life in sea
water at turtle in eye-sockets large salt glands were developed. When turtle
gets out on land, it can seem, that it “weeps”. Actually it is the work of
salt gland, removing surplus of salts from blood. The brine flows down on
each side of heads of the turtle having a rest on coast. From time to time
the reptile
rubs head against forepaws, cleaning off crust of salt.
On the coast turtles are basking after nourishing dinner, having stretched
flippers in sides. The gathering of turtles from afar is a little similar
to rookery of seals, but almost full silence here reigns: turtles do not
utter
loud sounds. Knock of carapaces when any turtle pushes another one, crawling
on sand, or hissing when two turtle males sort out their relationships in
breeding season, is only heard sometimes. Turtles live in gathering in common
and at
the same time separately: each of them perceives neighbours only as an annoying
obstacle at the way to meal or the sand heated up by sun. They are united
only with presence of meal – thickets of sea grasses and seaweed waving in
shallow
waters.
In water awkwardness of turtles vanishes: alternately moving by paws, they
dive to the bottom and bite sprouts of sea grasses. Each turtle is constantly
accompanied with school of small fishes: so it is much safer to them, besides
turtle muddles sand, facilitating search of tiny invertebrates. Some small
fishes scrap seaweed overgrown back of the reptile, others tear
rags of skin exfoliating at shed. The turtle has nobody to be afraid of:
monstrous sharks, capable to bite through half-and-half its carapace are
not found here.
Only before storm turtles creep out to the coast and even go deep into coastal
wood: waves easily can carry away any algal turtle to the sea or (that it
is even worse) simply break against rock.
At young algal turtles salt gland is not advanced yet. However, it is not
so vital for them: in youth they do not live in sea water. Algal turtle,
as against
sea turtles of Holocene, does not bury eggs at the sea coast. Fertilized
females leave coast, swim up rivers deep into woods of Zinj Land. Turtles
from islands
near continental coast should cross a passage for this purpose. In forest
turtles crawl out searching for soft ground, suitable for the nest arranging.
Having found the likely place, turtle digs out by hinder legs small hole
where lays about 30 rounded white eggs. After that it fills nest up with
wood dust,
some times crawls across it, and then comes back to the river. Weakened after
egg laying turtles are floating in current, having a rest. At this time they
eat of nothing.
If the laying will not be dug out by inhabitants of wood, after 3 - 4 months
young turtles will hatch out. They at once search for water, with the help
of sense of smell precisely determining concentration of water vapor in air.
Having found the river, young turtles live in it the first year of life,
gradually passing down from wood streams to the basic channel and further
to river mouth.
Later, when salt glands will develop, young turtles will leave in the sea.
Sexual maturity at them will come at the age of 10 years, and common life
expectancy can reach 150 years and even more.
Spike-headed tortoise (Cephalotestudo strobilocervix)
Order: Turtles (Testudines)
Family: Tortoises (Testudinidae)
Habitat: Galapagos Islands, bush and forest.
In human epoch Galapagos Islands were rather well-known due to huge tortoises.
Sluggish reptiles had become original “visiting card” of islands, and even
other name of Galapagos Islands is “Tortoise Islands”. The destiny of these
reptiles in historical epoch had balanced at the edge of nonexistence: in the
beginning because of extermination of tortoises by people, and then because
of their competition with introduced mammals. But tortoises managed to survive
successfully due to the world surrounded them. Galapagos Islands differ in
driest climate though are located in the ocean. At these islands there are
no rivers, and there are no constant water sources. In such conditions in combination
with hot climate few mammal could exist normally. Therefore an ice age when
the amount of deposits had even more reduced, introduced animals had started
to die out, and tortoises, on the contrary, began to master rather actively
becoming empty territories from which they were superseded earlier by introduced
and feral mammals.
Spike-headed tortoise is one of few descendants of representatives of native
fauna of islands. This is a large creature which has kept characteristic shape
of the tortoise: the carapace length reaches two meters at one meter height
and width about one and half meters. Outlines of carapace are rounded, above
the neck the edge of carapace is bent upwards, forming characteristic “collar”.
Carapace colouring is light grey with darker middle of scutes. Legs of this
tortoise are similar to elephant’s ones; they have large hoof-like claws and
thick corneous scutes. Weight of adult reptile reaches 500 kg and more; males
are approximately 20 % heavier than females.
This tortoise eats leaves and branches, and can reach them due to a long neck.
It is able to eat plants up to height of one and half meters above the ground.
But the neck creates a vital issue for this tortoise: it can not retract under
the carapace completely, and predators appeared at islands together with people,
could easily attack these reptiles. Therefore till the process of evolution
at tortoises the interesting protective adaptation giving to them fantastical
appearance was developed. At young tortoises on back edge of head and on neck
some ring lines of corneous spikes protecting head from bite of predator are
located. At adult tortoises bases of thorns gradually expand in continuous
rings of corneous scutes, and sharp tips of spikes gradually erase. But the
adult tortoise is able to protect itself actively: it bites, and its jaws are
very strong: they easily bite off pieces of lignificated trunks of local huge
cactuses. Young tortoises, protecting themselves from attack, brandish a head
(neck at this species is very flexible), trying to strike a blow to predator.
Spike-headed tortoises avoid open places, but in woods and bushes they thread
out the true circuit of wide tracks. These creatures are not inclined to communication
with congeners: they meet together only at rich in forage sites, but even in
this case each tortoise keeps separately, not paying attention to congeners.
These reptiles eat various vegetation including plants inedible for other herbivores:
they willingly eat leaves and branches of poisonous plants of spurges family,
and also prickly sprouts of cactuses making a basis of flora of Galapagos Islands
in Neocene.
The courtship season at these reptiles lasts practically the year round: presence
of the female ready to pairing stimulates activity of males. Courtship ritual
at these tortoises does not differ in special complexity: males push each other
away from the chosen female, hiss and strike each other by heads, trying to
hit in unprotected place between neck and forward legs. The male had won in
duel shows itself to the female: he walks around of her on extended legs, from
time to time striking on edge of her carapace. The female at this time retracts
head and legs under carapace, showing submission to him.
Till the year female lays eggs up to three times. In clutch it may be about
20 eggs a little bit smaller than goose egg by size. Female lays them in secluded
place in bush, and does not come back any more to the nest. Incubating lasts
about two months. Young tortoises at once leave nest and hide from enemies
in thickets of cactuses. They grow slowly, and reach the maturity only at 30-th
year of life at carapace length of about one meter. Up to this time many of
them perish from enemies – rodents and birds. But all the same the population
of tortoises of this species at Galapagos Isles is numerous. Life expectancy
at this species is extraordinary long; it also may make over 200 years.
Collarbill
tortoise (Ramphotestudo dorsognatha)
Order Turtles (Chelonia)
Family Tortoises (Testudinidae)
Habitat: tropical forests of Zinj Land.
Turtles are rather conservative group of reptiles: having evolved at Earth
in Triassic period, they actually did not change the anatomy features, differing
mainly by the habit of life. Protective tactics of these animals remained practically
identical from the moment of occurrence of these reptiles – at any age they
entirely relied on passive protection with the help of carapace.
Passive protection is not the best one – not receiving due repulse, predator
finds an opportunity to force a reptile by ruse to jut out from under the carapace,
and to kill it. Therefore various species of turtles used active defense for
protection: some of them became fast swimmers, and others began to bite. But
the most original way of active defense was developed by tortoises living in
tropical forests of Zinj Land. On the top part of the carapace above a head
at them the narrow strong wedge-shaped outgrowth of edge scutes, sticking up
forward, is developed. This outgrowth resembles a horn of the rhinoceros beetle
or a beak of some bird species. For this feature this tortoise is named the
collarbill tortoise.
Collarbill tortoise is the medium-sized reptile: length of carapace of adult
individual is about 30 cm, but usually it is much smaller. Its shape is typical
for turtles, but there are some essential differences. The head of this reptile
is very big and consequently it can not be retracted under the carapace completely.
But this feature does not prevent, and on the contrary, helps this tortoise
to defend. On the head of this tortoise the thick corneous scute with several
jags sticking upwards above nostrils and eyes was developed. Head and the outgrowth
at forward edge of carapace form the kind of “pincers”, like at males of Hercules
beetle (Dynastes): having pressed head to this outgrowth, the tortoise “bites”
predator, clamping its paw or tail, as if any alive trap. Strong cervical muscles
attaching to the top edge of carapace help this tortoise to compress “jaws”.
Force of the “bite” is so great, that even the adult tortoise can hang on aggressor
and do it till some minutes.
Despite of such protection, this tortoise nevertheless prefers to hide from
predators. It lives in underbrush, and leaves to feed in hottest time of day
when the activity mammal is reduced. This reptile eats mainly plants and mushrooms,
and especially willingly regales itself with fruit dropped from trees. Moreover
the collarbill tortoise eats eggs of birds nesting on the ground, and snails.
The carapace of the collarbill tortoise is colored contrastly: it is light
yellow with dark spots in the centre of each scute. Young tortoises have no
such protective adaptation; they are colored almost black color; also they
are timid and hide from enemies in bushes. “Beak” starts to grow at them at
the approach of sexual maturity – it happens approximately to the tenth year
of life. In same time on edges of scutes light corneous cover appears, and
the tortoise becomes spotty.
The basic destination of this “beak” is to be the weapon in tournament fights
of males. In courtship season they become even more aggressive, than usually
are: reptiles creep in forest, trying to “bite” by outgrowths any moving object
suitable in the size. It happens they hook by head and crush lizards and smaller
tortoises of other species, and even try to attack birds. Having met each other,
males try to hook by head and to overturn the contender. Thus they puff throat
and hiss – it is a unique sound which they can utter. Having met the female,
male begins displays: it creeps around the female, pushing her by “beak”. During
the display male taps with a head on “beak” at the carapace from below. The
female has lesser “beak”, and she does not render resistance to the displaying
male.
Pairing occurs quickly, and male abandons the female. From six to seven weeks
after pairing female lays 6 – 8 eggs in simple nest as a small hole, dug out
by hinder legs in wood ground. Having laid eggs, she crawls across the nest
some times, and then masks it additionally. For this purpose the tortoise digs
out some small shallow holes (“false nests”) near the true nest, fills them
up with the ground, simulating the dug nest, and does not care of clutch any
more. The incubating lasts about three months; young tortoises at once leave
nest and hide in bushes.
At the western coast of Zinj Land the close species lives: it is “fanged”
tortoise (Ramphotestudo odontophora). At this tortoise above the head deflexed edges
of scutes stick up, forming something like toothed jaw. Its head is wide and
angular, and above eyes strong sharp spikes serving for “biting” grow. This
tortoise also differs in increased aggression.
Mole tortoise (Subterraneotestudo talpina)
Order Turtles (Chelonia)
Family Tortoises (Testudinidae)
Habitat: islands (“oases”) of Mediterranean swamps.
Live creatures select various strategies of survival at change of environment
conditions. They can move in searches of suitable to life conditions or to
change habit of life, adapting to new environment. Such choice had been chosen
by Mediterranean tortoise (Testudo graeca) when conditions of life in the Mediterranean
had started to change. The sea without the connection with ocean because of
formation of the Gibraltar isthmus gradually had dried up, having transformed
district favorable for life earlier to rigorous desert with extreme conditions
of environment. Rather favorable conditions had kept only at tops of mountains
sticking up among salt desert - at former islands of the Mediterranean. Tortoises
dwelt there, had been compelled to adapt to such conditions. And the part of
population of Mediterranean tortoise had acted easy and more artfully: they
simply began to avoid influence of extreme factors, having disappeared under
the ground and having turned to the special kind of digging tortoises.
It is too difficult to believe that this descendant of Mediterranean tortoise
is the close relative of huge Antheos
tortoise playing the same role at these
small islands, that large ground herbivorous mammal at continents. The mole
tortoise almost constantly lives under the ground, occasionally creeping out
on a surface to get warm in beams of the morning and evening sun. In the afternoon
this reptile digs holes and disappears in them from the sun drying up heat.
Armour of mole tortoise is extended and rather high; its length is no more
than 30 cm. Scutes of carapace are smooth: it reduces resistance at movement
in holes. Main digging instruments of this creature is head with strong beak,
and thick sharp claws on forepaws. Eyes of this turtle are very small, and
sight sense is bad. During digging the ground the reptile blinks thick eyelids
at all. The firmest and dry ground easily yields to pressure of this creature:
by beak the tortoise loosens ground, and wide forepaws rakes it back. The back
edge of carapace is movably jointed with other carapace, and can fall down
with the help of contraction of special muscles. This adaptation, on the one
hand, protects tortoise from attacks behind, and on the other hand, helps to
rake away and push the dug out ground from hole. Hinder legs of mole tortoise
are armed with strong claws and become reliable support during ground digging.
This reptile eats mainly at the surface of the ground, leaving holes at night.
It eats greenery of treelike salttrees and other plants meeting in “oases”
of the Mediterranean, adding to leaves ripe fruits and small invertebrates.
At night these tortoises also can ravage ground nests of birds and eat carrion.
In the afternoon this reptile does not go hungry too: it undermines roots of
plants and eats them. Also it eats tubers and bulbs of grassy plants.
During the rigorous Mediterranean spring when rains from Atlantic and Northern
Sea overcome mountain ridges, at mole tortoises the courtship season begins.
At night, when fog falls on the ground, these tortoises leave holes. Between
males there are duels accompanying with knock of carapaces and hissing of excited
“grooms”. The male tries to impress the female, accompanying the courtship
with impacts of claws of forward legs on her carapace. Pairing occurs at night
on the ground surface. The second wave of breeding takes place in an autumn
but then pairing occurs not so roughly. After pairing the female lays in deep
hole eggs in amount no more than 5 – 6 ones. For egg laying the female chooses
a hole in bottom layers of ground, digs out a small hole in its bottom, lays
eggs and buries them. After that female crawls out and does not care any more
of posterity. Such process repeats twice per year. At this tortoise the interesting
feature had developed: oosperms can develop with high degree of probability
further, and from such kind of eggs the normal posterity hatches. The sex of
posterity is determined by an ambient temperature, therefore parthenogenetic
populations at this tortoise do not appear. But in different “oases” there
are the subspecies distinguished in size and coloring of carapace.
The incubating of eggs lasts about two months. Young tortoises are completely
independent. In winter when the temperature is cooler, the posterity of autumn
laying can remain in nest till the next spring. Young animals live in tunnels
dug by adult tortoises, and eat the same food, as adult individuals. They become
sexual mature at ten years' age and can live over hundred years.
Elasmosaurine
hydromedusa (Herpetomedusa elasmosauroides)
Order: Turtles (Testudines)
Family: Snake-necked turtles (Chelidae)
Habitat: rivers of tropical zone of South America.
Sometimes successful types of anatomy met in any group of animals, can be successfully
shown in another one, though in another form. This situation had taken place
at Neocenic water turtles of South America: among them one absolutely unusually
looking creature had appeared more similar to plesiosaurs for a long time missed
from face of Earth. Turtles are rather conservative by their anatomy group
of reptiles, but features of their structure have permitted developing of such
original design.
The inhabitant of great rivers of South America, the elasmosaurine hydromedusa,
is externally very similar to any dwarfish plesiosaurus: the neck length one
and half time surpasses length of carapace. It precisely repeats principle
of constitution of this sea reptile: long flexible neck permits to seize dexterously
the most agile catch under water, and the massive body serves as reliable point
of support, allowing making throw. In cervical of this turtle the number of
vertebrae is increased (up to 30 vertebrae), and joints between them are improved;
due to it neck has got significant flexibility and mobility. But such structure
has the return side: head of this turtle can not retract under carapace. But
this reptile lives far from coast, in thickness of water, and large predators
of South-American rivers, able to harm it, prefer coastal habitats.
Elasmosaurine hydromedusa is adapted to pelagic habit of life: it is tireless
swimmer seldom getting out on riverbank. Extremities of this turtle are oar-like,
wide and long, and lengthened fingers form similarity of flippers. At males
on forepaw two long thick claws are advanced, and on hips of hinder legs there
are long corneous heels. The reptile moves basically due to simultaneous flaps
of forepaws, hinder legs during swimming serve as rudders. To improve this
animal covered with carapace, keeping in water easily and do not sink, under
carapace thick layer of fat serving as float is accumulated. Additional buoyancy
to turtle is given with the porous bones impregnated with fat, and voluminous
lungs. Horn plates of carapace at this turtle in youth are as thick and strong,
as at other turtles of comparable size, but at the adult reptile they are appreciably
thinner, than at other turtles. Length of carapace is about 1.7 m, weight of
adult animal is up to 250 kgs. Tail at this turtle is short, serving basically
for storage of fat stock.
Scutes of carapace of the elasmosaurine hydromedusa are smooth and skintight
to each other. On medial scutes of carapace at turtles there are small vertical
keels, at males a little more sticking up, than at females.
The top part of carapace at the elasmosaurine hydromedusa is colored light
brown with darker spots in the centre of each scute. Abdominal shell (plastron)
is white with contrast black spots. Neck and extremities at the adult turtle
are colored gray-blue with dim white longitudinal strips, at young individuals
– dark-brown with grey-green strips. At males an iris of the eye is red, at
females it is pale yellow.
Head of the elasmosaurine hydromedusa is wide with strong jaws. Males are more
“large-headed”, than females. Edges of jaws are sharp, cutting, and tips of
jaws are bent like beak. This turtle eats fishes and other water animals. Young
turtles of this species search for water insects, river shrimps and crabs.
They live in coastal zone (it is the reason of their darker colouring in comparison
with adult reptiles) and do not compete to larger representatives of the species.
Growing up, they start to hunt fish in thickness of water and to develop deep-water
sites of the river. Adult turtles live far from coast and eat mainly fishes.
They also can catch water birds (seizing them from below from under water)
and eat corpses of sunken animals. The elasmosaurine hydromedusa almost does
not creep to land, only sometimes it has a rest, having clung by paw to trees
floating in river or fallen in water.
These turtles are solitary animals meeting together only in pairing season.
Because in river it is difficult to mark any conditional borders between sites,
turtles simply try to avoid company of each other. Sometimes some turtles surround
one large shoal of fishes, but during hunting they operate not together, differing,
for example, from dolphins or pelicans.
Hunting turtle tries to catch up planned fish and to push it to water surface.
It makes sharp lunges by head, biting fish. Sharp jaws of turtle can literally
shear across smaller catch, and to larger animal it puts deep wounds and catches
prey weakened from loss of blood. If the preyed fish is too great, turtle simply
bites off from it pieces and swallows them. Usually it eats catch while it
keeps on water, and does not dive for sunken one. The full turtle has a rest
and is basked at the sun, floating on surface of water and occasionally flapping
flippers to keep on current.
The pairing season is time when turtles pay attention to the neighbours though
any time. Elasmosaurine hydromedusas breed the most part of year, making a
break only in dry season. In northern part of area seasonal prevalence in breeding
of this turtle is not present. The female ready to pairing emits in water musk
liquid, involving males by smelling trace. Sometimes the chain of several males
follows such female showing the keenest interest to it. At turtles constant
pairs do not form, and female basically is indifferent, what male will be father
of its youngs. Males moving by breeding instinct, push away each other from
the female, and try to hook by claws for edge of its carapace.
Males never leave water, except for cases when the river or lake where they
live, become shallow and dries up. And females annually should make hard way
to land to lay eggs. They hardly move overland, dragging massive body forward
by flippers, and pushing by back ones. On land the elasmosaurine hydromedusa
is very sluggish and clumsy.
However, the female occupied with the nest making, is not defenceless, similarly
to sea turtles of Holocene epoch: powerful jaws and long neck allow it to keep
nest ravaging lovers at respectful distance. If any predator especially desiring
to eggs (for example, the otterodent,
large local river rodent) will approach too close, turtle warns of the intention
to protect, opening wide mouth and loudly hissing. If threats of the reptile
are not taken seriously, it can seize by sharp attack the uninvited visitor
and then it is possible to get rid of its stranglehold, perhaps, only having
torn off turtle’s head or having left in its jaws a fair piece of own skin.
And due to flexibility of the neck turtle can keep all-round defense, simultaneously
digging nest for the posterity.
In one clutch it can be up to 20 - 25 eggs. Their incubating lasts more than
three months, in colder southern areas delaying up to five months. Young turtles
with length of carapace about 5 cm live in shallow wood streams, eating small
fishes and shrimps. Dark colouring helps them to mask at the bottom among fallen
leaves. For improvement of masking at young turtles on sides of neck and legs
skinny scalloped outgrowths develop. Young turtles catch prey by sharp throw
of head, not leaving shelter.
At growing up reptiles behavior and shape change: colouring brightens, and
young turtle starts to catch fishes, chasing them in thickness of water more
often, and, at last, at the age of six years completely turns to pelagic predator.
The ten years' turtle becomes able to breed, and the age limit of this species
can pass for 130 - 150 years.
Atlantic bat turtle (Pteromedusa vespertilionina)
Order Tortoises (Testudinata)
Family False scuteless turtles (Neoathecae)
Habitat: tropical latitudes of Atlantic Ocean, Caribbean Sea, Pacific coast
of Central America.
In Neocene reptiles have made one more resolute attempt to win a sea inhabitancy.
Warming of climate in Neocene epoch, and also the mass extinction of cetaceans,
pinnipeds and many other sea inhabitants had permitted them to develop pelagic
habit of life. In tropical latitudes of Pacific Ocean the huge sharkodile,
one of last species of crocodiles reigns. Except for it, various turtles live
in sea. They are not descendants of sea turtles of Holocene epoch. Some species
of sea turtles of Neocene descend even from tortoises. The algal
turtle from
Tanganyika Passage separating Africa and Zinj Land is those, for example.
But this reptile does not leave far from the coast. But other turtles have
developed
true pelagic habit of life. They meet at open ocean far from coast, and need
the ground only for egg laying.
Water literally boils under impacts of mighty flippers, when one of such turtles
emerges to the ocean surface to make some breaths. It represents an impressive
show: the body is up to five – six meters in length at width over two meters.
And the span of huge forward flippers even exceeds the general length of the
reptile. They are very similar to wings of huge bat, hence the name of the
turtle – the bat turtle. Some loud breaths follow, and the giant plunges in
water again. Having emerged to the surface and having recovered breath properly,
this turtle may not emerge till two hours. It even sleeps hanging in thickness
of water, and only slightly moving by flippers.
The body of the bat turtle keeps the flattened streamline form characteristic
for turtles, but has no main feature of turtles – firm armour. Instead of corneous
scutes it is covered with thick rough skin, as at the leatherback turtle (Dermochelys)
extinct to Neocene. But bat turtles are not lineal descendants of these animals
– they descend from one species of freshwater turtles of South America. The
heavy armour is not necessary for this reptile - it prevents to swim, and speed
protects it from enemies, but not only it. The principal organ of movement
of this turtle is the pair of long forward extremities similar to wings. Flapping
them up and down, the turtle can swim accelerating for a long time the speed
more than 30 kms per hour, and at the short distance it even may accelerate
up to 60 kms per hour. Shoulder and forearm at this reptile are rather short,
but hand and fingers are very long: they amount more than half of length of
forward
extremity. Bones of fingers are wide and flattened, connected by elastic skin
membrane, and the short thumb is not connected by membrane and has some mobility.
With its help the male keeps the female at pairing, and the female clings to
ground creeping out to the land for egg laying. The back edge of forward extremity
is joined to side of turtle with the help of rag of mobile and extensible skin.
This feature makes the bat turtle very similar to gigantic bat swimming under
water. Back extremities of the reptile are modified to short and wide flippers
serving for turns and maintenance of balance. Their length hardly probable
makes third of length of forward flippers.
The body of this reptile is colored softly dark grey color with small amount
of dim dark spots on back. The bottom part of body at these turtles is light
grey. Such colouring helps the animal to mask in thickness of water. But masking
and speed not always can help to escape from predators, especially to young
turtles. Therefore this species has one more weapon very effective against
underwater predators, from large squids to the sharkodile. Already at early
age at young turtles in cloacal bladders glands secreting very poisonous paralytic
substance develop. It represents transparent yellowish liquid; escaping from
predator, the turtle emits it out in water. When the predator swims through
the cloud of such substance, receptors in its mouth and olfactory bodies appear
paralyzed till some hours. Besides these turtles are able to protect themselves
actively, biting the enemy by strong jaws. The adult turtle of this species
having reached the maximal size does not have enemies.
At bat turtle there is wide flattened head with short, narrow and high beak.
They eat various food which may be found in sea. Atlantic bat turtle differs
in bias to vegetarianism. It often meets by big groups at algal fields near
New Azora Island, and near thickets of sea salad in Caribbean Sea. Young turtles
of this species keep near to coast and eat macroalgae growing at the bottom,
and adult individuals pass to pelagic life. Only females once a year come back
to land to lay eggs.
Pairing at these turtles takes place at open ocean. It is preceded by primitive
courtship displays. At this time males chase the female and push each other
away from her by body. During courtship displays the skin on head of the male
becomes bright: along the side of head through an eye black strip stretches,
and the throat turns bright blue color. The iris of the eye at the male is
white, and it is clearly distinguished on the background of head. The winner
male tries to keep the female, seizing her by beak for edge of the carapace.
When he succeeds to do it, he creeps on the female and couples with it. Pairing
lasts till some hours.
After the pairing in organism of the female eggs ripen within approximately
5 months. They are too small for the multiton giant, but all the same they
have the impressive size: length is up to 20 cm at the width about 10 cm. The
clutch of this reptile may number up to 100 – 120 eggs. All turtles of this
species breed in the same place – in South America, at the land area between
Amazon and Hyppolite rivers. They swim up-stream in these rivers to tens kilometers
far from the coast, and lay eggs at sandy riverbanks. The nest of this turtle
is a hole about one and half meters deep. The female digs eggs in sand and
leaves them to the mercy of fate.
If 3 months of incubating pass successfully, young little turtle with the length
of carapace about 15 cm hatches from egg. The hatching of young turtles passes
almost simultaneously, but each young turtle should independently dig the way
through the thickness of sand for itself. Such work lasts up to three or four
hours. Usually it starts in the afternoon when the sun warms up sand well,
and is finished up to the night. Young turtles appear in water simultaneously,
form schools and swim downstream to the sea. The mass downstream migration
of young bat turtles takes place at night within approximately one week, but
separate singles swim downstream till about next two weeks. The considerable
part of them becomes prey of fishes and other inhabitants of the river whereas
schools of young turtles suffer less damage from predators.
Young bat turtles grow rather quickly: till the first years of life they increase
2 – 3 cm in length; farther up to 60-years age they grow up to 5 cm per one
year. At this time they reach maturity, but further their growth is slowed
down. But they reach the really the monstrous size due to the large life expectancy:
the bat turtle may live over 250 years.
Other species of this group live in oceans:
Pacific bat turtle (Pteromedusa velonectes) differs from the Atlantic congener
in smaller size: the length of the adult reptile exceeds 5 meters seldom, and
usually exceeds 4 meters only a little. At this reptile colouring of body is
gray-blue without dark spots. Sometimes the reptile gets an appreciable greenish
shade because of symbiotic green algae settling on its skin. Forward flippers
of this turtle are narrower, and back ones are more lengthened, rather than
at the Atlantic species. This turtle swims faster, than the Atlantic species.
It also differs in greater aggression, and frequently attacks the enemy: some
sharkodiles have deep scars on a body, and sometimes the tip of the flipper
at them appears bitten off – these are traces of counterattacks of turtles
of this species. Pacific bat turtle eats mainly pelagic invertebrates – jellyfishes
and gardenersalpas. It breeds at Hawaii, swims upstream in rivers and lays
eggs in soft forest ground.
Dwarf bat turtle (Micropteromedusa australis) lives in the Southern hemisphere.
This species, on contrary to the relatives, do not keep away from coast. It
lives along the coast of Meganesia and New Zealand, and the separate population
inhabits Eyre Gulf, not having contact to ocean populations of this species
at all. The length of body of dwarf bat turtle does not exceed two meters.
It also differs in more advanced claws on forward flippers and massive head,
and its beak is not cutting, but crushing. This reptile is zoophagous – it
eats molluscs, crabs and dead fishes. Populations of open ocean breed at small
islands near the coast of New Zealand; for this purpose individuals from the
coast of Meganesia gather to schools and cross Tasman Sea. The population from
Eyre Gulf breeds at northern coast of Tasmania. For the breeding females of
this population had to cross sandy shallows in the mouth of gulf till the inflow.
The idea about the existence of this group of animals was stated by Tim Morris, Adelaide, Australia.
Leaf-looking
gecko (Phyllogekko platysomus)
Order: Squamates (Squamata), suborder Lizards (Lacertilia)
Family: Geckoes (Gekkonidae)
Habitat: woods of Equatorial Africa.
If large animals can expect to own force and size in case of danger, tiny creatures
had to resort more often to tricks to not get to somebody for dinner. One of
prevalent dodges in animal kingdom is masking. Managing to pretend to what
you are not (and mainly - does not causing appetite in predator), it is possible
to receive quite good chance to survive. Various insects frequently act so,
simulating branches, knots, leaves of various degrees of freshness. In Neocene
epoch in tropical woods of Africa another kind of imitator had appeared: it
is small forest lizard, the gecko simulating tree leaf.
Leaf-looking gecko lives on trees, inhabiting branches in forest canopy at
height of several tens meters above the ground. It is rather large for the
gecko though its body length including tail does not exceed 20 cm, and tail
accounts about one third of general length. The body of this lizard is strongly
flattened in dorsoventral direction, simulating leaves of tree. On edges of
body and tail the wide skinny border grows, forming scalloped outgrowths: it
helps animal to look rather convincingly, simulating insect-eating leaves.
Besides outgrowths on edges of body help to reduce up to a minimum treacherous
shadow can come to naught masking of the reptile. Head of leaf-looking gecko
is flat, eyes are strongly spread and look in sides. Above eyes triangular
skinny outgrowths stick up in sides, masking them at sight from above.
The body shape is harmoniously supplemented with colouring. The body of leaf-looking
gecko is colored from above bright green. Along back thin light strip passes
simulating middle nerve of leaf, and on each side there are short cross strips.
At edges of lateral outgrowths of body there are some brown irregular-shaped
spots: it is the imitation of damaged leaves. Even eyes of this lizard are
perfectly masked: the iris of the eye is colored green, and vertical pupil
may be voluntary narrowed up to the thinnest crack, imperceptible at passing
to the hidden lizard. When this gecko sits on branch or on leaf, having turned
up paws under body, it cannot be founded while it’ll move.
But the belly of leaf-looking gecko is colored deliberately contrast: at males
it is black with red spots and dubs, and at females it is one-color black one.
Such distinction helps to individuals of different sexes to distinguish each
other.
To live on the tree, it is not enough to have only cryptic colouring. Paws
of many geckoes, even largest ones, are well advanced and also are very tenacious
due to set of microscopic fibers taking place on their bottom side. The leaf-looking
gecko is not exception here: its wide flat fingers are adapted to keeping even
on smooth surface of leaves.
Main food of this species of geckoes is insects. Large cockroaches and small
termites – all of them are devoured with identical pleasure. The leaf-looking
gecko supplements insect diet with small snails and ripe fruits with soft pulp,
even little bit begun to rot.
By their nature leaf-looking geckoes are solitary animals. They occupy the
certain territory somewhere in crone of tree, and zealously preserve it against
neighbours. Each lizard declares its rights to territory by the loud cries
similar simultaneously to bark of tiny doggy and voice of the newborn crocodile.
If any gecko will come to the territory occupied by another one, owner of territory
at first tries to banish it, having started to shout more loudly and more often.
If the newcomer does not go away, the owner leaves shelter and creeps towards
to the unbidden visitor. Both opponents start to show themselves, having risen
on legs and from time to time sharply nodding heads. But such demonstration
does not proceed long: the newcomer either leaves in good time or fight begins.
Both lizards bite each other, drag each other by legs or lateral outgrowths
of body. Usually in this case both opponents get numerous scratches from sharp
teeth of the neighbour.
Only time when such selfish creatures willingly suffer presence of strangers
(but not everyone!) at their territory is breeding time. In courtship season
males of leaf-looking gecko show bright belly, involving females. For this
purpose they hang on branch headfirst, gripping it only by back paws. Thus
they utter the special cry similar to chirp of bird. The female has entered
to territory of the male, should show two signals: belonging to fair sex and
humility. Coming nearer to the male, she turns a head by bottom jaw to his
side. It allows to see color of throat of the female, having no bright spots,
and simultaneously tames aggression of the male as very weak spot is shown
to him.
Pairing lasts some minutes, and then female leaves territory of the male and
twice zealously starts to protect her own one: in her organism ripening of
eggs begins. About three weeks after pairing the female lays in tree-trunk
hollow or behind peeled off tree bark two or three eggs. For one year the female
can make up to three - five such clutches.
First minutes shell of freshly layed egg is soft and sticky, but in air it
quickly hardens, and egg appears firmly pasted to substratum. About two months
later tiny (about 4 cm long) copy of the parent hatches from it. Young leaf-looking
geckoes have smooth outgrowths on sides of body and uniform green colouring
without brown spots. At their growing up jags at edges of body appear, and
in colouring in the beginning the pattern of leaf nerves and then dark stains
simulating decay will be shown. At the age of 18 - 20 months young lizards
can breed.
The leaf-looking gecko keeps mainly on branches of trees. And the closely related
species, lichen
gecko (Ph. lichenodermatus), lives on wood trunks and large branches.
It is similar to leaf-looking gecko, differing from it in larger size (up to
30 cm) and some features of appearance. On surface of its body numerous warts
and knobs imitating lichens on tree bark are located. Colouring of this species
is well matched with habitat: it is the combination of grey and brown colors
with greenish spots. Skinny edging of body at it is smoother.
The lichen gecko, just as leaf-looking one, eats insects have sat on bark.
Generally the diet of lichen gecko includes butterflies and capricorn beetles;
it catches them creeping closely and sharply rushing at prey. As many butterflies,
spending daytime on tree bark, have cryptic colouring, this gecko finds them
with the help of very keen sense of smell.
Flower
gecko (Anthogekko scandens)
Order: Squamates (Squamata), suborder Lizards (Lacertilia)
Family Geckoes (Gekkonidae)
Habitat: Northern Australia, rainforest canopy.
Lizards pass to vegetative food very seldom. The majority of their species
eats insects or small vertebrates. One of reasons of this phenomenon is considered
to be easier digestion of food of animal origin in comparison with vegetative
food. But in tropics where climate is constantly warm, there is a significant
amount of herbivorous reptiles. During evolution vegetarian species appeared
in various families. And even among especially carnivorous lizards there are
the species eating sweet and high-calorific fruits of plants. In Neocenic woods
of Northern Australia one species of geckoes have completely changed its habits,
having turned from predator to vegetarian. But the food which it uses differs
in refinement: it is flower nectar.
The Australian flower gecko spends all life in forest canopy at dizzy height.
Here, in empire of wood crones and epiphytic plants it finds enough flowers
rich in nectar.
This lizard grows only to 15 cm length, and about half of it thin tail accounts.
Flower gecko is dexterous acrobat: its legs are rather long, and on fingers
characteristic for these lizards combs, permitting clambering on even smooth
surface of leaves, are advanced. This gecko moves slowly, but in case of danger
it can make very fast throws and even jumps up to meter long.
The skin of this lizard is colored green with bright red legs and spot on nape;
stomach and throat are white. Large eyes have straw-colored iris with narrow
vertical pupil.
The head of flower gecko is narrow, and tongue can extend rather far. Practically
constantly these geckoes walk over the territory, searching for flowers of
plants. Because stocks of this food are rather small, lizard constantly inspects
territory, zealously preserving it from competitors. Each lizard declares rights
to territory, uttering loud sharp sounds similar to peal of hammer against
anvil.
On the tip of tongue of flower gecko fibers forming hairy brush, convenient
for nectar gathering, grow. In addition to nectar plenty of pollen gets in
stomach of gecko. Pollen of many species of plants is not digested, but pollen
of some plants serves as additional food source for lizard. Also flower gecko
willingly regales itself with fruits begun to rot.
The breeding period of this species stretches practically for the all year:
at any time in wood there are young lizards of this species. The female lays
only 2 - 3 eggs, but egg layings can repeat up to four times once a year. For
breeding female chooses deep tree-trunk hollows or cracks under peeled out
bark where eggs are inaccessible to casual predators. In breeding season males
willingly admit females to their territories, but after pairing banish them.
The young growth hatches from eggs after 10 - 11 weeks. Young geckoes differ
from adults in brighter colouring: at them head, paws and tail are red, and
only on back there are some green spots. They spend the most part of time on
flowers of trees and epiphytes, disappearing at approaching of adult neighbours.
At their growing up more and more green spots merging in a continuous background
appear on their bodies.
Mouse-eating
gecko (Macrogekko myophagus)
Order: Squamates (Squamata), suborder Lizards (Lacertilia)
Family Geckoes (Gekkonidae)
Place of an inhabiting: temperate forests of New Zealand, wood litter.
In human epoch fauna of New Zealand haâ undergone radical changes: in this
“lost world” inhabitants unknown earlier, mammals, had appeared. Among them
there were both herbivores and predatory species. Newcomers had started to
destroy local animals, and to the end of human era only separate species had
remained from endemic fauna.
But influence of alien species to fauna of New Zealand was not only negative.
Some species of local animals had developed new kinds of food being absent
at islands before human colonization. Murine rodents and even small predators
belonging to weasel family became the basic prey of one surprising creature.
In deciduous woods of New Zealand ground is covered with thick layer of fallen
foliage. In it numerous insects crawl, and small rodents hunt them. They obviously
feel like in safety, but this impression is deceptive Attentive eye of predator
hidden literally right at mammal’s very nose observes of carefree rodent. One
careless movement – and rodent is seized. For a share of second leaves laying
before it turn to head and paws of large-headed lizard. Reptile catches small
mammals by wide mouth and compresses by jaws. Quiet crunch is heard, and little
body of small mammal lifelessly hangs, and the hopeless peep breaks. Lizard
slightly inclines head sideways, catches prey more conveniently, and starts
to swallow it, inclining head alternately to both sides. Eventually only tail,
sticking up from mouth of lizard, remains from unlucky rodent.
When the job is done, lizard creeps out of shelter: the successful hunter has
received dinner which will be sufficient to it to nearest few days. Now main
task is to find good shelter where nobody will disturb this lizard.
The large lizard is the mouse-eating gecko - one of representatives of endemic
New Zealand fauna, the descendant of native species of these islands. When
small predatory mammal had appeared at islands due to human will, the majority
of New Zealand reptiles had been exterminated by them. But some gecko lizards
had survived, and one of their species has turned to predator.
It is a reptile up to 70 cm long; this one is true giant among geckoes, usually
do not exceeding 20 cm in length. It is remarkable, that before human colonization
of these islands in New Zealand very large species of geckoes was found. At
the mouse-eating gecko there are large head with strong jaws, rather short
paws and short tail.
This lizard hides in leaf litter, trapping small mammal, birds and reptiles,
and catching them by fast throw. This species avoids competition with predatory
mammals due to habit of life: it is active in the afternoon while predatory
animals go to hunting at night. For improvement of masking the skin of mouse-eating
gecko is covered with lines of warty outgrowths, and flat pointed outgrowths
stick up above eyes. The skin is colored brown with yellow “nerves” and dark
spots. Even eyes of reptile are masked: the iris of the eye is colored beige
with twisting vertical brown strips. The pupil of reptile looks like vertical
crack. Having slightly dug in rotten leaves, lizard becomes imperceptible for
possible prey.
At wood geckoes tail serves as the balance weight during tree-climbing. The
mouse-eating gecko spends most part of time at the ground, therefore the tail
at it had became much shorter, than at wood relatives. In tail stock of fat
is accumulating permitting to wait cool winter days. Though in habitats of
mouse-eating gecko snow never falls, in winter it becomes appreciably colder
and appetite of reptile reduces. Mouse-eating gecko spends winter in hibernation,
hiding in deep tree-trunk hollow or in crack between stones. Lizard keeps some
activity even in the most cool winter time, slowly creeping in the refuge.
At the end of winter when sun heats up stones and trunks of trees, the lizard
creeps out to get warm not for a long time.
When short cool winter comes to an end, mouse-eating geckoes leave shelters
and start to feed again. During first weeks after hibernation they look poorly:
tail is very thin, and skin on body here and there is wrinkled. But gradually
they are eaten off: at first they catch insects, and then small animals. Eggs
of birds are special delicacy, and geckoes willingly climb for them on bushes
and trees.
When lizards restore forces after wintering, tournament fights of males begin.
The male at this species is larger and more large-headed than the female. In
courtship season its eyes change color: the iris of the eye becomes bright
red. This color is supplemented with light pink mucous membrane of mouth.
Gecko males share forest to set of sites. The owner of site creeps on tree
trunk or stone, and declares rights to territory by cries. The voice of the
mouse-eating gecko resembles yelping of small dog. Having noticed the female,
the male starts to cry even more often and louder.
In clutch there are 2 - 3 eggs by size like chicken ones, with dense skinny
shell. Shell of freshly layed egg is sticky. The female lays them usually in
tree-trunk hollow or in crack between large stones. Here, in conditions of
more stable microclimate, the incubating passes more successfully. The female
protects place of clutch, and drives neighbours off from it, puffing throat
and hissing.
The incubating lasts about two months. When young lizards hatch from eggs,
female leaves post and any time continues usual life. For a season she can
make only two layings, but survival rate of posterity due to protection of
a laying is rather high.
Young mouse-eating geckoes eat insects. Later they pass to feed by rodents,
and in the beginning ravage their nests and eat newborn cubs. At the age of
three years they become able to breed.
Butterfly
gecko (Papiliostellio quasivolans)
Order: Squamates (Squamata), suborder Lizards (Lacertilia)
Family: Geckoes (Gekkonidae)
Habitat: Indonesia (Jakarta Coast), crones of trees of tropical rainforest.
Sites of land open to ocean winds near equator are a place where a plenty of
pre-glacial forms of life had kept. In Neocene some of them have died out,
not having sustained a competition to newcomers from more cool areas, but as
a whole variety and originality of life in these places remained up to the
mark. Reptiles are presented especially richly in equatorial area. In Neocene
they have started to occupy new ecological niches, turning to surprising creatures.
One of such Neocenic reptile species had evolved on the long site of land earlier
representing the Big Sunda isles which in Neocene had merged to common belt
of land - Jakarta Coast. In conditions of winds constantly blowing from ocean
this creature had adapted to gliding flight. It is the small lizard – gecko
about 20 cm long including tail. It would look quite usual lizard, marking
among many neighbours only with bright red eyes. But at once feature for which
this lizard is named "butterfly gecko" is evident: on each side of
the body scales of this lizard are extended and have turned in feather-like
outgrowths with fibrous back edges. Such feature already had appeared during
evolution process at the Triassic reptile Longisquama dwelt in the Central
Asia. But at it such scales had grew along back in two parallel lines. But
if about their applicability at the fossil reptile long disputes had taken
place their role at the butterfly gecko does not cause doubts: with their help
it can make long gliding jumps from tree to tree. The length of "feathers" reaches
10 cm, they are slightly bent back. Especially long "feathers" grow
on sides at once near forepaws. To hips they gradually become little, on the
tail basement they are very small, but on the tip of tail they form the small
blade, suitable for jump driving. Small muscles are connected to the basis
of every "feather". Therefore the butterfly gecko can lift and lower
them and also change their inclination during a jump. All fingers of the butterfly
gecko are wide, tenacious, with hooked claws.
The top side of body of the butterfly gecko is painted not strikingly: it is
green with brown spots and grey points. By color and the texture the skin on
back of the lizard successfully imitates bark and lichen. But in breeding season
the reptile changes: from below "feathers" are colored much more
brightly, red-colored with white tips, and they are actively used in courtship
games. The male shows them to the female, having lifted upwards and having
opened, as if the peacock tail. Thus it marks time on stretched legs, trying
to keep to the female by side. The throat of the male gets at this moment white
color with black longitudinal strip.
This lizard is a predator eating insects and snails, cracking their shells.
It can catch flying insects like flies and butterflies.
This species breeds, laying eggs. In clutch there are only 2 rather large eggs
hiding by female in tree-trunk hollow. For one year egg laying can repeat up
to 10 times. Zygotes are kept in female organism for a long time and quickly
turn to eggs, therefore after one pairing the female can lay fertilized eggs
5 – 6 times.
The incubation lasts about 2 months. Just hatched geckoes are about 5 cm long.
They have no “feathers”, but their growth begins almost at once, and at the
age of 2 month reptile already completely becomes “fully fledged” and can make
long jumps. At the age of half year gecko becomes completely mature, and its
life expectancy in wildlife is about 5 - 6 years.
Duckweed
basilisk (Nanobasiliscus lemnodromus)
Order: Squamates (Squamata), suborder Lizards (Lacertilia)
Family: Iguanas (Iguanidae)
Habitat: South America, slowly flowing rivers, swamps and lakes.
At the boundary of Holocene and Neocene the area of tropical woods had been reduced
everywhere at Earth. Only in Indonesia, Equatorial Africa and South America small
sites of rainforests had kept. Only few inhabitants of this type of ecosystems
had managed to survive up to Neocene. Some inhabitants of rainforest had died
out because of chasing from the part of people; others had not managed to keep
viable populations at isolated sites of solid earlier area. But the small part
of inhabitants of tropical wood had kept up to Neocene and evolved actively.
Among them there were mainly medium-sized animals not demanding a plenty of food
and able to endure short-term deterioration of inhabiting conditions. Reptiles
having such abilities, had received in Neocene the right of the further evolution.
Among them fantastical and original lifeforms have appeared.
One of surprising reptiles lives in rainforest reservoirs. It is tiny lizard
with brightly yellow corneous crest on head. It can be seen more often on leaves
of water lilies where this reptile is heated, having stretched paws in sides.
Length of this creature is about 20 cm including long tail making more of half
of the general length.
While the lizard is quiet, it differs from other neighbours with nothing. Only
its rear paws are approximately twice larger than front ones, and toe tips are
edged with thin bristle-like outgrowths of scales. When above surface of leaves
the fly flies by, the lizard reacts instantly: it jumps up, and rushes for the
fly. When the insect turns off to water, the reptile does not lag behind: slaping
by paws on surface of water, tiny lizard jumps, snaps fly right in air, and runs
back to leaves right on water surface. Lizards of basilisk genus (Basiliscus)
dwelt in historical time in South America had this skill. This reptile has inherited
and has developed this unique skill, having specialized to life on water surface.
It weighs so little, that can easily run on thickets of duckweed (Lemna) spread
on surface of water. Hence the name of this lizard – the duckweed basilisk.
To be simply very small – it is obviously insufficiently to have ability to run
on water surface. In body of duckweed basilisk also qualitative changes have
taken place: its bones are strongly pneumatized, air bags penetrate them, as
at birds. The constitution of this reptile is very fragile – at it there are
thin paws and long thin tail. The adult reptile weighs no more than 20 grammes.
The skin of the lizard is colored bright green which shade can vary depending
on condition and mood of the lizard. Stomach of the reptile is white. The skinny
crest on head of the lizard is colored lemon yellow shade. It is an attribute
using which lizards distinguish congeners.
Duckweed basilisk can not only run but also swim, though it makes it reluctantly.
In water the lizard easily can fall prey to various predators – fishes and turtles.
Besides duckweed basilisk is too tiny to swim quickly enough and to escape from
underwater predators. And one more danger is that this tiny lizard can easily
cool down in water and becomes inactive. Therefore duckweed basilisk escapes
in water only when there is no another way to hide from predator (for example
when the reptile is attacked from air by bird of prey or bat). The main way of
rescue from enemies at this reptile is fast run.
Duckweed basilisk eats almost exclusively insects living on surface of water.
It eats water scaters and catches larvae of mosquitoes in leaf axils of floating
plants. Occasionally duckweed basilisk eats small snails (more often it is made
by females shortly before to egg laying), fry and tadpoles living at the surface
of water. In dexterous jumps duckweed basilisk catches damselflies and the flies
hovering above water.
Duckweed basilisk is a tiny creature which is quickly heated up and quickly loses
heat. At night when it becomes colder, reptile gets into axils of leaves and
falls into catalepsy. At night the duckweed basilisk is very sluggish and easily
can fall prey to various predators, therefore it tries to hide more reliably.
In the morning lizard gets out on leaves of plants and is heated in first beams
of sun.
It is unprofitable to be too heavy to animal having such habit of life, therefore
at females of duckweed basilisk one ovary is reduced, and eggs develop and are
laid by two – three ones. The courtship season at duckweed basilisk lasts a year
round. The male of this species is smaller than female, and it also differs with
more advanced red coloured gular pouch. It arranges displays for females, climbing
on stalks and peduncles of aquatic plants sticking up above the surface of reservoir.
Involving females, male stirrs head up, puffing ular pouch. When two males meet,
they begin bloodless and transient tournament. Males show gular pouches to each
other, are shaken on peduncles, and in near fight try to push each other out
in water. At this moment they become striped.
The female ready to pairing shows the submission to the male, having light green
colouring. After pairing it undertakes risky travel on coast, and lays eggs among
moss thickets on tree trunks at height up to five meters. Cycles of breeding
repeat each two weeks.
Young reptiles hatch approximately after three weeks. Young lizards go down from
tree trunks and search for reservoirs where they will spend, probably, all life.
They easily settle on floating plants.
Life expectancy of duckweed basilisk makes no more than 4 – 5 years. But the
female starts to lay eggs at the age of five months.
The idea of existing of this animal was stated by Rafael Silva do Nascimento, Brazil.
Salt-loving
skinkfish (Ichthyoscincus halophilus)
Order: Squamates (Squamata), suborder Lizards (Lacertilia)
Family: Skinks (Scincidae)
Habitat: Mediterranean salt swamps.
When in early Neocene Mediterranean sea has completely dried up, rich fauna
of fishes and other water animals inhabited it earlier had left to non-existence.
After changes of climate water by means of plentiful rains gradually began
to come back to extensive salt desert of Mediterranean, having formed extensive
shallow reservoirs and bogs. But in these places no one fish may be found:
the salinity of water is too great for them, and Mediterranean is not connected
to any sea of World ocean. Nevertheless, at the bottom of Mediterranean reservoirs
live creatures teem: larvae of different species of flies, and also small crustaceans,
steady against the high contents of salts in water. But if the local birds,
flightless crested
flamingoes eat crustaceans,
larvae of flies living at the bottom of reservoirs, feel like in relative safety
from them. And nevertheless they have enemy.
In greenish because of seaweed and muddy water long white creatures slide,
wriggling. They are similar to fishes, but they are not fishes: from time to
time they emerge to surface of water, putting out muzzle tip, and breathe with
characteristic puffing. But they also are not amphibians: any newts or salamanders
will not endure so salt water. When one such creature creeps out on stone,
it becomes evident, that it is the reptile: its body is covered with dense
granular scales. It is the lizard – the skinkfish.
Desert inhabitants, skinks have developed adaptations for survival in conditions
of shortage of water. They prosper in most droughty places of planet. And in
bogs of Mediterranean these features were useful to them, having permitted
to master new habitat, atypical for lizards – supersalt reservoirs.
The length of body of skinkfish is about 60 cm; from which tail amounts about
2/3 (males are longer, than females, but their body is more graceful). Body
of animal is cylindrical; tail is flattened from sides and edged from above
and from below by wide skinny plica, permitting to swim. Head of the reptile
is pointed in front, covered with thick horn scales. Eyes of skinkfish are
protected by eyelids grown together – at this reptile it is unblinking “snake”
sight. Nostrils of skinkfish are shifted upwards and protected by skinny valves
which are closed when lizard dives. Paws of reptile are similar to mole’s ones
– they are short and thick, with long claws. Hinder legs are little bit longer
than forepaws. Because the reptile spends significant part of life in water,
belts of extremities are poorly joint to backbone that gives the skinkfish
some advantages.
The body of reptile is covered with dense corneous cover shedding similarly
to snake skin – it exfoliates from edges of mouth, and gets off by entire piece.
During shedding skinkfish rubs body against stones and twists to rings, rubbing
different parts of body against each other. Colouring of skin of skinkfish
is grayish-white without spots and strips.
In physiology of this reptile there is one feature directly connected to habitat:
very large kidneys stretched practically along all body from shoulders up to
pelvis, partly coming even in tail due to elastic connection of pelvis and
backbone. These kidneys effectively eliminate from blood salt, plentifully
treating to animal with food.
Skinkfish feeds with few species of insects had mastered life in Mediterranean
swamps: larvae of flies and water
beetles. Fodder areas of skinkfishes stretch in shallow waters, where under
the bright sunlight microscopic algae expand on stones plentifully. The basic
catch of skinkfish, larvae of blood-sucking
flies, scraping this seaweed by mouths, keeps there. Usually skinkfish
cautiously creeps to catch, drifting in thickness of water. It is not afraid,
that it will be noticed – larvae of flies are completely blind. But they sensitively
react to slightest movements of water; therefore any careless movement of lizard
will frighten them off. Having swum up closely enough, skinkfish makes sharp
movement sideways, creating whirlpool. Current of water tears larvae off from
stone, and lizard picks them up by mouth. But even if larvae have felt approaching
of the enemy and have hided between pebbles at the bottom, skinkfish will not
stay hungry: it simply will dig out bottom by powerful sharp-clawed forepaws
and tip of muzzle, and will seize larvae.
When the lizard seizes larvae, it faces with main difficulty for all creatures
living in this place: in its organism salt can get. And here the interesting
mechanism of protection was developed at the reptile. In soft palate skinkfish
has plica tightly closing gullet. It interferes to casual swallowing of salt
water. In mouth of lizard there is submaxillar throat pouch for catch, therefore
skinkfish may not emerge to surface too frequently - having filled this bag
with catch up to the full, lizard creeps out on stones and outside of water
eats caught larvae. But under water lizard all the same should open mouth and
to prevent getting of salt in blood through mucous membranes of mouth, they
are protected from brine by slime rich in protein with addition of fats making
this slime water-repellent.
From time to time skinkfishes creep out to coast to have a rest and swallow
caught larvae. Usually each lizard has stone chosen for this purpose, but outside
of water they quietly tolerate company of each other, and at times at one convenient
stone up to ten lizards gather. They do not try to take away each other’s catch,
because, swallowing caught larvae, lizard may not open mouth at all. Only having
crept out on land, it accurately contracts throat, squeezing out water from
mouth. Sitting on stone, skinkfish from time to time raises head, squeezes
out from throat pouch by effort of its ring muscles caught larvae one by one,
and swallows them.
On land skinkfish moves hardly: it pushes body by movements of tail, because
hinder legs of reptile are rather weak, and pelvis is attached to backbone
by flexible and extensible ligaments. Such feature of anatomy permits to skinkfish,
however, to avoid some difficulties which wait for reptiles in this salty world.
Skinkfishes do not lay eggs – they are live-bearing reptiles. Pairing of skinkfishes
takes place on land: it excludes salt getting in organism of female through
oviducts. Before pairing males arrange courtship demonstrations: they lift
heads upwards, inflate throat pouches and shake them. Thus skin on throat of
the lizard becomes bright red because of extended blood vessels. When the female
comes nearer to chosen male, showing by lowered head the submission, he twists
around of her body, and the fast pairing occurs.
Pregnancy of the female lasts about three months, and then she gives rise to
unique young on land. Young skinkfish is practically a copy of the adult reptile;
its length makes approximately half of body length of mother. To bear and to
give rise easily to such large posterity extensible connection of pelvis and
backbone helps to the female. Birth of youngs occurs 2 times per one year:
during pairing there is a fertilization of several ovocytes from which only
one develops, and other thus are “inhibited”. After birth of first young the
second ovocyte starts to develop.
After birth of second cub other zygotes do not collapse: they survive through
the most adverse season, but their destiny is not determined yet. If the female
will not receive visual signals from other males, at “spare” fertilized ovocytes
there is a chance to develop to high-grade youngs. In such way the population
can restore, basically, from few fertilized females. Presence of other males
causes changes of hormonal level of the female, and “spare” zygotes collapse.
But at the same time new ovocytes ripen, ready to fertilization.
Prickly
agama (Echinagama spinosa)
Order: Squamates (Squamata), suborder Lizards (Lacertilia)
Family Agamas (Agamidae)
Habitat: steppes to the west from Fourseas.
Agamas are one of the most successful families of lizards. In Old World their
representatives during Cenozoic superseded representatives of other groups,
adapting to various conditions of inhabiting: from deserts up to tropical woods.
High abilities to adaptation have permitted these reptiles to survive successfully
during an ice age.
From eastern coast of Fourseas (Garagumy beach) up to bush wastelands of Mongolia
steppes, overgrown by grasses, were stretched. Here there are not many rivers,
and fauna is presented by mainly drought-resistant species. The interesting
species of agamas – prickly, or hedgehog, agama – lives here.
When this lizard is quiet, it almost by nothing differs from other representatives
of family. It is the lizard of approximately half meter long including tail
and large head. On body and lateral faces of tail scales are lengthened, having
turned to spikes. Scales on shoulders are especially long – up to 3 cm. By
shape scales resemble three-edged blade: they are flattened, and on the external
side longitudinal edge passes. These scales are colored dark-brown, being especially
visible on background of grayish-yellow skin. They grow by longitudinal lines,
forming on the top side of body of animal regular pattern. On stomach spikes
are much less, and skin is colored lighter, being of almost white color. At
the male throat is colored bright red and spike scales are white. At the female
color of throat does not differ from color of stomach. The bright throat pouch
is using by male in courtship demonstrations.
Prickly agama like its neighbours is afraid of birds and large mammals, and
hides from them in shelter – cracks in stones and holes of rodents. But it
is not afraid at all of snakes being enemies of many lizards of such size,
because it is able to protect from them originally.
Having seen snake, lizard takes menacing pose: it rises on straightened legs
as the toad, and puffs. It has some air bladders connected with lungs, and
special valves allow to force in them air at an exhalation. As a result the
reptile quickly inflates, and its visible size is increased more than twice.
Covering its body lengthened scales stick out, turning to the terrible weapon.
Puffed up, lizard keeps at predator’s movement. If the distance too decreases,
it swings by tail in sides. From birds and mammals prickly agama uses one more
way of protection: being strongly puffed up, it slightly “blows off”, and thus
utters loud whistle through densely compressed jaws. If enemy does not recede,
lizard beats it by prickly tail, or makes lunge, striking it by spikes of sides
and shoulders.
Courtship games of prickly agama are similar by something to displaying at
man-o-war birds from far Holocene. Males get on separately sticking up branches,
and puff throat pouch, becoming appreciable from afar. Each male protects the
territory from contenders.
During rain season (spring) the female makes 2 layings: in first one there
are up to 10 - 12 eggs, in second one (2 – 3 weeks later) - no more than 10
eggs. The posterity hatches in second half of summer. They spend winter in
holes of rodents, fencing off from restless neighbours by several ground “fuses”.
The young reptile reaches maturity at the age of two years.
Leaf-headed agama (Compressisaura angustissima)
Order: Squamates (Squamata), suborder Lizards (Lacertilia)
Family: Agamas (Agamidae)
Habitat: humid subtropical woods at southern and western coasts of Fourseas.
During an ice age the rests of heat-loving European flora and fauna appeared
“compressed” at the narrow strip between cold glacial tundras stretching from
the north, and dry salt deserts at the place of Mediterranean Sea dried up
when strait of Gibraltar had closed for ever at movement of Africa to the north.
There were only few “oases” where the rests of Holocene flora and fauna dragged
out a miserable existence among new species appeared in glacial epoch.
In early Neocene the flora and fauna of Europe had gone through the rebirth:
when glaciers had thawn and at Earth extensive shallow seas had appeared again,
the climate became more humid and steady. The huge Fourseas lake isolated from
the ocean, formed in early Neocene, softens the heated breath of Mediterranean
hollow and supplies with moisture the mysterious world of subtropics of South-East
of Europe. This world is isolated from tropics of Asia and Africa by mountains
and salt desert, therefore it was occupied mainly by descendants of local fauna
and flora. Representatives of heat-loving southern fauna are not very numerous
in woods of Balkans and Caucasus: there are only separated species of small
vertebrate animals, insects and few plants had reached here over mountains.
In warm and damp woods at the southern and western coast of Fourseas reptiles
are numerous. One of their representatives is the leaf-headed agama, the small
tree-climbing lizard living on tree trunks.
Lizards represent easy catch for various predators. The majority of their species
has no poison and is too small to protect itself actively. Therefore till the
evolution process lizards either studied quickly to run, or developed various
ways of masking for protection against predators. The leaf-headed agama shows
one of such kinds of protection.
Body of this reptile is strongly compressed from sides and high: it hardly
exceeds 2 cm in width at length of the reptile about half meter. The height
of body of this lizard amounts about 10 cm; on its back the skinny crest with
slightly cut up edge grows, on head there is also thin jagged comb. When the
lizard freezes sitting vertically on bark of tree, it is similar to the exfoliating
piece of bark. One more advantage of this skinny crest is an opportunity to
be warmed faster: in the morning lizard creeps out on tree trunk and turns
sideways under beams of rising sun.
The fantastical body shape is supplemented with cryptic colouring which varies
over a wide range: from green with narrow white strips simulating leaf nerves
up to light grey or brown with longitudinal lines imitating color of tree bark.
At this reptile even eyes are disguised – the iris of the eye is colored yellow
with tiny brown speckles. Such colouring is successfully combined with any
variant of skin colouring.
Paws of the leaf-headed agama are thin and have tenacious sharp-clawed toes.
To keep on tree trunk stronger, at back edge of forearms and on the internal
side of shins spike-like scales develop. When the lizard sits on tree bark
upwards a head, they are stuck in bark and the reptile keeps on trunk without
the special efforts. The tail is long (it accounts more than half of general
length of animal) and thin; its tip is extended. It serves as the balance weight
when the leaf-headed agama jumps from branch to another. Also the attacked
lizard can whip small enemies by tail. The basis of tail has some small skinny
outgrowths continuing a crest on back at the top side.
The leaf-headed agama is the diurnal reptile. Usually it sits on tree trunk
as precisely as possible imitating color of its bark. This lizard is a predator
and eats insects and spiders, but can attack small wood frogs and ravage bird
nests. Usually it expects while suitable catch will come nearer to it itself,
catches it by short throw, quickly swallows and freezes again not to be noticed
by larger predators. It spends night in shelters – cracks of tree trunk and
in narrow cracks under scaled out bark. The hidden lizard supports by paws
against bark and tree trunk, and tenaciously keeps by claws. Only few nocturnal
predators are able to pull out the leaf-headed agama hidden this way.
Features of constitution impose restrictions to some vital processes of this
lizard. In thin body of the female many eggs can not form at once, therefore
the female of this species lays eggs in small portions - 2 – 3 ones at once.
The egg of leaf-headed agama is very much extended and covered with limy shell.
Till first minutes after laying the shell is soft and sticky, then on air it
hardens quickly. This feature permits the reptile to lay eggs in well-protected
shelters – on tree trunk under bark where this animal usually hides at night.
The pasted egg keeps strongly on tree trunk and is inaccessible so to the majority
of predators.
In connection with such breeding feature the courtship season at leaf-headed
agamas is strongly dragged out: it takes place since late spring up to middle
of an autumn. Courtship display of the male happens rough: having felt a smell
of the female ready to pairing, it begans the display – the male rises on extended
legs, puffs an extensible throat pouch of brightly-yellow color with black
spots, frequently “nods” a head and expects for the appearing of the female.
If the female is not shown for too long time, male starts to follow its tracks.
When the male sees the female, his demonstrations become even more active:
he starts to utter abrupt whistling sounds, blowing air from throat pouch through
slightly opened lips. When near one female two males appear, between them fight
is possible; in this situation contenders bite each other, beat by tails and
try to push each other away from the female. But usually males avoid fight
and simply try to make impression of the bellicosity against each other. They
puff throat pouches, whistle and whip tails, trying to strike the contender.
The male had losed fight in any case has an opportunity to breed: till the
peak of breeding season in forest females ready to pairing meet frequently.
Readiness of the female for pairing happens about each 10 days, right after
the next laying. For one season the female may lay more than 30 eggs: it is
even more, rather than it happens at other lizards living in the neighbourhood.
The incubating of eggs lasts about 2 months, but last autumn layings develop
much longer: their development is delayed for all winter. From such eggs young
animals hatch approximately in middle of spring. Adult reptiles hibernate in
deep tree-trunk hollows. Their aggression to each other is reduced in an autumn,
and they gather for wintering by groups of some tens of animals. In winter
animals are inactive, but approximately at the end of March when it becomes
relatively warm, they one by one leave the common shelter and occupy territory
suitable to life.
Pangolin lizard (Neocordylus armatura)
Order: Squamates (Squamata), suborder Lizards (Sauria)
Family: Girdle-tailed lizards (Cordylidae)
Habitat: Southern Africa, savannas of various types.
Human epoch is characterized by change of borders of natural zones. At this
time there was a reduction of areas occupied with forests and grasslands, but
areas of deserts extended. It took place because of irrational economic activity
of people. In historical epoch the significant territories occupied earlier
with productive natural communities, had turned to deserts and became unsuitable
for human life and for agriculture. But in these places rather large number
of animal species was kept. The greatest distribution of deserts was typical
for Africa to the north of equator, and for Near East. In South Africa extensive
territories also were occupied with deserts – Namib, Kalahari and Carroo. In
these deserts rich fauna of reptiles evolved and was kept. One of Neocene species
of South-African fauna is pangolin lizard.
Pangolin lizard is a small reptile of strong constitution, with very powerful
and clawed forepaws. It is the descendant of Holocene girdle-tailed lizards
(Cordylus) characteristic for South Africa.
This species has a little changed in comparison with the ancestor: the length
of adult individual seldom exceeds 20 cm. This lizard has rounded head covered
from above with strong corneous plate, flattened body covered with cross lines
of large pointed scales (hence the name), and thick armored tail covered with
scale rows overlapping each other, and similar to pine cone. This tail serves
for reserving of fat stock, and in courtship season is used for displaying
to females – they more willingly are coupled with successful and full males
which tail is full of fat. Protecting itself from small predators, lizard beats
them by tail, as if by buldgeon.
Living in small groups – 1 – 2 males (one of which is obvious subdominant)
and 5 – 6 females – these yellowish-brown reptiles something resemble miniature
anteater monitors from deserts of Meganesia. Peaks of activity of pangoline
lizard fall to morning and first half of day when their forage – various small
and medium-sized invertebrates – has not come to the senses yet after night
catalepsy, and is easy for catching. Lizards are heated in beams of rising
sun on stones or walls of termitaries, and then start search of food. Forage
of these reptiles includes termites, ants and other insects and invertebrates.
Due to strong jaws these lizards easily chew strong armours of beetles.
By way of life pangoline lizards divide in two groups – “tramps” and “homebodies”.
“Homebodies” are lucky beggars managed to settle near large ant hill, or, even
better, near termitary which is exposed periodically to their attacks: due
to thick skin pangolin lizard can rather painlessly suffer relatively large
number of stings of ants, termites, and others small, but poisonous insects.
It breaks a surface of termitary by forepaws, and simply licks off running
out insects.
“Tramps”, on the contrary, have no constant residence. Almost all of them are
young males did not manage to secure a constant colony of fodder insects. Therefore
all the time they are occupied with searches of their own colony, and are compelled
to spend much more time for search of daily portion of food – any insects or
arachnids, which they can eat. This is rather dangerous occupation, because,
despite of hardness of skin and camouflage colouring, pangolin lizards are
regularly eaten by various animals, from larger lizards, and up to large spiders
and scorpions, attacking young reptiles. Besides they constantly should search
for shelter to wait in shadow hotter second half of day, and to spend the night
in safety.
At the middle of dry season pangolin lizards have a new care: the courtship
season begins. Homebody males get on any eminences – for example, on tops of
the “own” termitaries, and start to hiss loudly, puffing and showing bright
throat having violet or yellow spots. Basically, this representation is intended
not for females, but for tramp males of this species, which would like to expel
the owner from its house after long fight. During the courtship tournament
two males push each other by breast, creeping on top of termitary, ant hill,
stone or other eminence. Two or three fights usually are enough to reveal the
weakest one, which leaves a place of struggle, conceding to the winner territory
and females, which are immediately fertilized.
This species of lizards is ovoviviparous. At the end of summer, in the beginning
of rainseason, females give rise to 2 – 3 live youngs. Among females of pangolin
lizards there are no “tramps”. If any female does not live in constant colony,
it may be only very young female had left to search for new place for residence.
Adult females also can be “tramps”, but only when the colony of insects in
which they ate, was exhausted and lost, that happens, but too seldom. On the
contrary, almost all males leave a place of their birth to the beginning of
the next dry season, and do not come back to it even to the beginning of courtship
season, preferring to win a place for life somewhere at the distance. In such
way pangolin lizards succeed to avoid inbreeding.
Birth of young pangolin lizards is dated to the beginning of rainseason, because
at this time at termites, ants and other social insects of South Africa courtship
flights begin. In same time other insects, grasshoppers and locusts, burst.
At this time in nature there is a greatest variety of food for young pangolin
lizards, opportunities for growth of their colony are greatest, and aggression
of adult individuals is reduced. But further, somewhere in second half of rainseason,
all young males and some females leave a place of the birth, being banished
by old male and sometimes by other females.
This species of reptiles was discovered by Bhut, the forum member.
Lizardboa (Sauroboa trachycephalus)
Group: Scquamates (Squamata), suborder Lizards (Lacertilia)
Family: Blindworms (Anguidae)
Habitat: humid subtropical forests at the coast of Fourseas – from the Balkan
up to Caucasian Peninsula.
Ice age at the boundary of Holocene and Neocene had become serious test for
European herpetofauna. Glaciers held down by continuous armour the most part
of Europe had forced heat-loving reptiles to recede to the south, or had simply
exterminated their populations. Therefore in early Neocene the herpetofauna
of Europe had began to form practically from zero. Some widely settled European
species had survived at the south of former area, and had returned to habitats
of their forefathers in new quality. Among such species there was one representative
of blindworm family, the glass-snake (Ophisaurus apodus). This species of snake-like
lizards had successfully survived in agrarian landscapes of human epoch, and
its descendants had taken a dominant position in herpetofauna of European subtropical
forests.
The descendant of this large lizard had turned to true giant over 3 meters
long. By its powerful constitution this reptile is similar to small boas and
hence is named lizardboa. As against to true snakes which are strict predators,
lizardboa is omnivorous one. This reptile feeds on various large insects and
small vertebrate animals, and also willingly eats soft fruits fallen from trees.
In appearance of lizardboa there is one more feature distinguishing it from
snakes - at this lizard there are mobile eyelids, and it can blink. Also at
lizardboa the cervical narrowing very characteristic for snakes is poorly expressed.
The skin of this reptile is covered with small scales forming a continuous
cover. Colouring of lizardboa helps to mask in underbrush, waiting for prey
approaching. The basic background of colouring is yellowish brown. On it a
spots of brown color are scattered making three faltering longitudinal lines
– along back and on each side. On tail spots merge to continuous strips with
rough edges. The head of reptile is covered with set of small irregular-shaped
spots.
Lizardboa leads passive enough habit of life. In day time it hides in wood
litter or under bushes, waiting for approaching of small animals suitable for
eating. Attacking them, this reptile strikes a blow by head which is covered
with strong corneous armour; impact stuns prey, or at once kills it. Protecting
against large predators, this lizard applies similar tactics: it rises on tail
like cobra, loudly hisses, and if the enemy does not recede, strikes sharp
and strong impacts by head.
At the end of the summer and in autumn lizardboa is actively fattened, gathering
the stock of fat necessary for successful wintering. Per bumper-crop years
the diet of this reptile may more, than half consist of berries and fruits.
Before wintering reptile does not eat, exempting intestines from the rests
of food.
Few large reptiles expand far to the north. Only the huge lizard gila-dragon
(Helodermopsis monstrosus) lives in North America almost so far at the north.
In conditions of seasonal climate reptiles face to the necessity to go through
winter period adverse for life, running into more or less long hibernation.
Shortly before an autumn cold snap lizardboas begin to search shelters for
wintering. Lizardboa winters in burrows which digs itself, or occupies ready
burrows of various mammals. Usually few animals can resist to this reptile
if it has chosen their burrow for wintering; therefore lizardboa usually does
not have problems with search of winter habitation. In areas where there are
karstic caves with narrow entrances, these reptiles gather for wintering by
tens. At this time lizardboas are inactive and rather tolerant to relatives.
In spring, when stabile warming comes, lizardboas leave shelter in which they
had spent cold season, and start to feed actively. At this time they behave
extremely aggressively, and the adult reptile can even eat young growth of
own species. It is connected to vital necessity – after wintering the exhausted
reptiles as soon as possible should restore the physical shape and start breeding.
The courtship season at these reptiles begins approximately one month after
the end of hibernation. Males colour very brightly: their colouring becomes
very contrast. In courtship dress male is almost black-and-white with slight
yellowish shade on white areas of body. Males become very active. They creep
in forest, expelling contenders from the territory, and mark borders with odorous
liquid. If two males about identical in force meet, they arrange noisy combat,
coiling bodies and biting each other. Having met the female, male tries to
press her body to the ground and to turn on back in order to couple with her.
If the female is not ready to breeding, she tries to turn to dense ball preventing
male to unwrap her body. If the female is ready to pairing, the pair of reptiles
coils and coupled during several hours. At this time male is very aggressive,
and attacks even animals much larger than its own size.
Lizardboa belongs to egg-laying reptiles. During two months after pairing in
organism of the female up to ten large eggs develop. During the pregnancy the
female becomes cautious and keeps mainly at warm forest clearings where sometimes
some individuals of this species gather at once. Such behaviour is connected
with the fact that eggs of lizardboa pass the first stage of incubation in
organism of the female. Then the female lays them, digging in forest litter.
The further care of posterity is not characteristic for this species. The incubation
proceeds till about one month, and young individuals about 30 cm hatch. They
differ from adults in cross-striped colouring. The diet of young ones consists
of insects and berries.
Lizardboa becomes completely developed at the age of 4 years, at length up
to 170 cm. Life expectancy of this reptile makes more than 60 years.
Ant-monitor
(Myrmivaranus flagellicaudis)
Order: Squamates (Squamata), suborder Lizards (Lacertilia)
Family: Monitor lizards (Varanidae)

Habitat: savannas of Australia.
Long and thin tongue of reptiles of order Squamata, is constantly put outside
to gather information about the environment and to carry it to Jacobson’s organ
at the palate. It is frequently able to penetrate into various cracks and apertures.
Therefore would be quite possible to it to get in the future any more function,
which was earlier not met at present group of animals.
In human epoch monitor lizards (Varanidae) were considered as the most progressive
family of lizards. One of variety centers of this family is Australia. In Neocene
one of survived representatives of monitor lizards family from savannas and
semi-deserts of this continent, using an abundance of various species of social
insects, had passed from predating habit of life to feeding by this specific
catch. Before this species Australian echidna (Tachyglossus) and less specialized
banded anteater, or numbat (Myrmecobius) had such diet. This reptile became,
thus, their ecological analogue, taken place of these animals in savannas of
Neocenic Australia.
Reaching more than 2 meters in length, the Australian ant-monitor is rather
sluggish and slow, and rather peaceful in comparison with its relatives. It
has powerful enough claws, both on front and on hind legs, with which breaks
the ground and nests of colonial insects. Long and thin tongue, doubled at
the end and covered with sticky saliva, allows to catch insects and to draw
them in mouth. Saliva also involves by taste and smell some ants, which get
on tongue when lizard pushes it in their nest. Teeth of this reptile are considerably
reduced; they are small and sharp, located only in forward part of jaws.
Thick scaly skin protects body from stings which are put to monitor lizard
by insects, furiously protecting ravaging nests. Head of this monitor lizard
is covered from above with almost continuous corneous armour. On back of ant-monitor
there are sticking up enlarged scutes also used as passive protection. They
form cross belts on all back of the reptile, representing reliable protection
against medium-sized predators.
In case of danger the ant-monitor protects itself by impacts of tail, on which
end some rows of pointed scales were developed, and also by big powerful claws,
making aggressive lunges aside the enemy.
Colouring of body is soft: from yellowish-grey to dark brown tones (there are
individual deviations in color), lighter yellowish strip through lateral part
of neck and shoulders serves for recognition of neighbours. For strengthening
of contrast with colouring of body it is shaded from above and from below with
darker strips. Color of this strip directly depends on physical condition of
animal. At meeting two reptiles of this species turn heads aside, showing this
strip and estimating thus physical opportunities of each other.
The basic food of ant-monitor is social insects. This monitor lizard feeds
with them as in nests (destroying them with strong claws), as on their tracks
or in thickets. Perhaps, only soldier ants devouring all alive on their way,
represent the certain danger for it, but their more peaceful neighbours frequently
become its food. In searches of insects ant-monitor is able to rise of hinder
legs, and base by forepaws against trees trunks, surveying bushes and branches
in searches of insect nests. But because of massive armour this reptile does
not differ in abilities of tree-climber. Also this reptile can feed on ground,
digging out underground nests of insects, or eating underground larvae of beetles
and cicadas.
Ant-monitors are single animals, but in areas of dense settlements of social
insects they keep by groups of 3 – 5 individuals. Usually these reptiles constantly
wander in savanna, not being late for a long time in any place.
Males at this species are larger than females. Ant-monitor lays eggs (up to
20 ones) to unusual incubator: into termitarium. After all clutch is laid,
female leaves it, and termites repair the damaged wall of nest. Eggs appear
in very favorable conditions, and besides, they get a smell of termitarium.
Therefore practically nothing threatens to clutch and young ant-monitors, and
the first time they grow in environment of own food. The adult female, contrary
to habits of majority of lizards, does not leave nest at all. It marks termitarium
becoming an incubator for its clutch, and also remarkable objects in its vicinities
with musk liquid from glands opening on hips, and keeps beside. It will drive
off adult neighbours from nest during all term of incubating, but approximately
when the young growth hatches from eggs, it leaves a post. The first ant-monitor,
destroying termitarium in searches of food, involuntarily releases young growth
from imprisonment.
Young ant-monitors have brighter and contrast colouring, than adults. Primary
color of their body is yellow, on it brown cross strips pass. Stomach is white;
along neck and on shoulder brown strip passes. Later colouring changes: strips
on body disappear, and strip at shoulder becomes brighter: on it light stains
appear, merging at the adult reptile to continuous strip.
Young ant-monitors are still too weak to break open nests of termites independently.
Therefore they keep near to adult reptiles, and feed after them at cracked
termitariums. They will reach the size of adult animal approximately to 6 -
to 7 years, though they’ll become able to breed already at 3-rd - 4-th year
of life.
This species was discovered by Arseny Zolotnikov
Crocodile
monitor lizard (Pseudosuchus varanoides)
Order: Squamates (Squamata), suborder Lizards (Lacertilia)
Family: Water monitors (Aquavaranidae)
Habitat: rivers of Southern and Eastern Africa, south of Zinj Land.
After the ice age number of crocodiles, last representatives of prospering
in far past Archosauria subclass, had sharply reduced and they have died out
practically at all area. But in warm and damp climate of Neocene when many
finny rivers and lakes have appeared, the place of large fish-eating predators
did not remain empty: it was occupied with representatives of large monitor
lizards. Once in Cretaceous period monitor lizards have already achieved short-term
success, having evolved to predatory mososaurs – true horror of seas. In Neocene
the opportunity to make the second attempt has appeared at them, and they again
have taken advantage of it, becoming ancestors of separate family of water
monitors, including predators similar to crocodiles of last geological epoch.
They are settled in rainy tropic areas of Old World: in Africa, at East-African
subcontinent, south of Arabia, Hindustan, in South-Eastern Asia and Indonesia.
In Nile which in Neocene had changed the channel and flows across former Sahara
desert as in prehistoric times, representatives of water monitors are not found:
there they are replaced by other predatory river reptile, huge
crocoturtle (Archotrionyx vorax), the representative of soft-shelled turtles.
At the coast of Tanganyika passage separating the East-African subcontinent
from Africa, the crocodile monitor lizard, one of widespread species of this
family, lives. It is the huge water reptile (its length is up to 5 - 6 meters),
externally similar to crocodile with longer neck and without characteristic
skin osseous plates. The skull of crocodile monitor lizard is more than half
meter long. It is rather wide and flat. Eyes of reptile are shifted in top
part of head and stick up above it a little. Haw has a role of “underwater
glasses”, permitting monitor lizard to see normally under water. Nostrils of
crocodile monitor lizard open at the end of muzzle that allows the reptile
to breathe, only minimally displaying itself for catch. Edges of nostrils can
close automatically at diving. Under water this monitor lizard finds possible
catch with the help of sight and strongly advanced chemical feeling: the reptile
from time to time analyzes water by tongue like snake.
Paws of crocodile monitor lizard are well advanced, animal easily moves on
the ground. On toes claws, with which help monitor lizard tears apart large
catch, are advanced. Palamas between toes of reptile are not present. The main
swimming organ at the crocodile monitor lizard is long tail (its length is
about half of general length of reptile). On tail the skinny edge is advanced,
stretching up to middle of back. The skin of this monitor lizard is colored
greenish-grey with pattern of longitudinal lines of darkly-green spots. Stomach,
chest and throat are covered with soft yellowish-white skin.
Crocodile monitor lizard is active predator and scavenger. Its basic forage
includes fishes, but the reptile equally willingly eats ground animals, for
any reasons got in water, and during river floods searches corpses of sunk
animals. Teeth of this reptile, as against to crocodile’s ones, resemble more
teeth of shark: they are leaf-shaped with sharp saw-toothed edges. Attacking
large animal, reptile puts to it deep cut wounds by teeth.
These reptiles are rather tolerant to each other, and frequently it is possible
to see, as they gather on riverbank by small even-aged groups. The most part
of day adult crocodile monitor lizards bask at the sun. If they become hot,
huge lizards slip in water, wet skin and creep out to riverbank again, or hide
in shadow of trees, or wallow in dirt. But such picture can be observed only
when reptiles are full. Hungry crocodile monitor lizard is dangerous creature.
It arranges ambush on shallow, near to favorite watering places of ground animals.
Usually this reptile lays at the bottom, occasionally putting out from water
tip of muzzle to breathe. Through river bottom monitor lizard feels steps of
animals going to watering place. When the catch is located, monitor lizard
cautiously creeps up in bottom as close as it is possible to animals drinking
water, and makes sharp throw, trying to seize the chosen prey to the muzzle.
If the attack is successful, reptile jerkily fells catch and drags it in water
to drown. Thus it strongly grips it by jaws, not giving to prey any chance
to escape.
Young crocodile monitor lizards eat at first insects, and then pass to more
essential catch: frogs, small fishes, birds and animals had fallen in water.
Crocodile monitor lizard eats exterminated catch alone when it is not so large.
But if carcass is too large, it should hasten: the successful hunter is immediately
surrounded by hungry neighbours, and everyone strives to bite off from another's
catch richer piece. Sometimes near catch serious fight springs up. But teeth
are not used, in other case after each such conflict the population promptly
would decrease. Monitor lizards fight, pushing away opponents by all body,
striking impacts by head and scratching by claws. Teeth are used only for demonstration
of force: driving away neighbours from lawful catch, crocodile monitor lizard
widely opens mouth, showing lines of sharp teeth, but does not try to bite
the contender.
Being adapted to life in water, the crocodile monitor lizard confidently feels
on land. It easily walks, and can even run to small distances. Sometimes it
hunts on land, hiding near track of large animals. Here excellent masking colouring
helps reptile. It attacks nothing suspecting prey when it walks beside. Sharply
having turned around, monitor lizard strikes blow of tail on legs of prey,
and then, having turned to it by head and rushes on animal trying to rise,
seizing its neck or thorax. Even if the prey will escape, it is practically
doomed: teeth of crocodile monitor lizard put to prey such wounds, that it
quickly perishes from loss of blood. And the reptile easily finds wounded prey
by blood trace. As against water turtles, the crocodile monitor lizard easily
can swallow catch outside of water, and teeth with which it is possible to
bite off suitable piece easily, favorably distinguish it from crocodiles. Crocodile
is compelled to snap for its any sticking outside part and to turned around
axis to dismember large catch. And such trick succeeds only in water.
The crocodile monitor lizard is very enduring, and it can even stay short time
in sea water. Sometimes on “rafts” of floating trees these reptiles can be
carried away far to the ocean, receiving an opportunity of settle at islands.
They had crossed this way Tanganyika passage and have occupied the East-African
subcontinent, and also had settled in Southern Arabia. On East-African subcontinent
this species had formed the separate dwarf form (Pseudosuchus varanoides
carcinivorus) up
to 3 meters long. The dwarf crocodile monitor lizard eats mainly fishes and
freshwater crabs.
The breeding season at these reptiles stretches almost for all year, except
for dry season at edges of natural habitat. Usually the male (on the average
it is about meter longer than the female) begins caring: it chases female ready
to pairing, seizing by paws for the basis of her tail (usually males of lizards
keep females by teeth, but teeth of crocodile monitor lizard can put painful
wounds). If the female is not ready to accept caring of the male, it can shake
him from herself, having swept by the ground or having swam through driftwood.
If some males try to care to one female, there can be severe fights between
them: contenders push each other away from the female, strike impacts by head
and scratch by claws. If the competition becomes especially sharp, teeth are
used and then fight may terminate in heavy traumas. In colonies of crocodile
monitor lizards it is quite often possible to see animals with bitten off toes,
injured skin and knocked out eyes, crippled during courtship tournaments.
Caring for the female, male pays to her signs of attention: it rubs against
her head and throat. On riverbank male lays near to female, driving away from
her probable competitors and when the female leaves in water, follows her.
Pairing of reptiles takes place in water and repeats some times. After pairing
male some time stays near to the female.
Pregnancy at crocodile monitor lizard lasts about three weeks. When the female
feels, that there comes time to lay eggs, she leaves riverbank and searches
for secluded place in forest. In moisturized and friable wood ground she digs
out by hinder leg hole about half meter depth, and lays in it about two tens
eggs by size like goose ones. When all eggs are laid, female digs nest in and
by bottom jaw rakes up atop leaves and branches of it. The care of posterity
at this species of reptiles comes to an end at this moment, and female leaves
nest.
The incubating lasts about two months. The length of just hatched young retile
is only about 25 cm. By colouring it differs from adults: its skin is emerald-green
with faltering cross strips of black color. Fin plica on tail is well advanced,
and the young growth is able to swim and dive since the first day of life.
But the first day of life is the hardest for the future river tyrant.
Young monitor lizards should fulfill very hard task: to dig independently the
exit to the surface, and then to find way to water. It succeeds not to all
ones: if the place for nest is chosen unsuccessfully, the overflow after rain
river may simply inundate nest. A part of clutches may be founded and dug out
by predatory animals, they destroy part of young monitors. In the river both
predatory fishes and adult neighbours hunt young crocodile monitor lizards.
Therefore the just hatched young monitor lizards searches shelter from cannibal
neighbours in thickets of marsh plants where adult crocodile monitor lizard
is not able to creep through. In total only posterity from one third of laid
eggs survive up to monthly age. But at two-year-old age they reach one-and-a-half-meter
length, and many of former enemies easily can turn to catch. And the eight-year
reptile being about four meters long has practically no enemies. At the same
age crocodile monitor lizards can breed. Life expectancy of this reptile can
reach 70 years.
Pike
monitor lizard (Varanesox velonatans)
Order: Squamates (Squamata), suborder Lizards (Lacertilia)
Family: Water monitors (Aquavaranidae)

Habitat: islands of Indonesia, South-Eastern Asia.
Change of climatic conditions and natural accidents accompanying them were
reflected at the reproduction of plankton by the most pernicious way. Biological
efficiency of seas had sharply decreased, that had caused extinction of most
part of coastal fish-eating organisms. But ecosystems of rivers not so strongly
depend on sea plankton, and only separate species of animals had suffered here.
General efficiency of rivers had practically not decreased.
It had permitted to some species of terrestrial animals to make attempt to
pass to aquatic habit of life. In Indonesia conditions had especially favored
to it. At the ice age the ocean level was lowered, and islands had merged to
some common areas of land that had allowed to ground animal to settle widely.
Among successful migrants there were various reptiles, including monitor lizards.
When glaciers have thawed, the common land appeared divided to set of islands.
Due to plentiful rains at islands the set of rivers had appeared. One of optimum
ways of adaptation to this change of inhabitancy was the passing to life in
water.
Coast estuaries are rich in life – here larvae of fishes growing up in brackish
water and small shrimps meet, amphibians and insects live in freshwater sites
of flowing rivers, and also there are different species of waterfowl. Medium-sized
lizards of monitor lizards family had started development of this promising
inhabitancy, having evolved to essentially new form – pike monitor lizard.
This almost completely aquatic lizard most advantageously lives in shallow
warm gulfs. Its close relative is African crocodile
monitor lizard (Pseudosuchus varanoides). It differs in larger sizes being
less adapted to aquatic habit of life.
The pike monitor lizard, on the contrary, spends significant part of time in
water. It has streamline body shape, but has kept many features of common terrestrial
reptiles. Main movement organ at this lizard is the tail; it is short and compressed
from sides with oblong fin at the end. Extremities are rather small, flatten
like crocodile paws, having claws at fingers and toes. Hinder legs are larger
than front ones. At the land pike monitor lizard moves clumsily and reluctantly;
it does not creep far from reservoir.
Pike monitor lizard reaches one and half meters long, but more often it is
smaller. The skin is covered with smooth, small, densely fitted scales colored
dark green with cryptic vertical stripes of grayish-yellow color.
Eyes and nostrils are shifted to the top part of muzzle that permits to look
over vicinities, only slightly having put out muzzle from water. Head of the
reptile is rather large: approximately the fifth part of the general length
of animal. Neck is almost not expressed.
This reptile swims by means of tail and paws. Certainly, in quickness this
monitor lizard concedes to fishes, however it successfully hunts them from
an ambush. Usually the reptile hides among water plants, or driftwood. Thoroughly
having recovered breath and having inhaled air in lungs, it can stop breathe
during approximately quarter of hour. Thus its blood circulation is switched
in such manner that blood supplies first of all brain and heart. Muscles exist
due to internal stocks of chemically fixed oxygen.
Less often this monitor lizard attacks amphibians and nestlings of waterfowl,
and also eats carrion.
It swallows small catch entirely, taking it to swallow from head. This reptile
can bring large fishes or dead animal which cannot be swallowed at once, for
convenience to shallow water, and then tears it apart by teeth and claws of
forepaws.
In the morning, or after meal, pike monitor lizard quite often creeps out of
water to get warm on driftwood or to sandy spit in river channel, keeping up
for environmental conditions. On land this reptile behaves very cautiously.
Any sharp sound or suspicious movement it regards as danger, rushing in water
and hide deeply in thickets of underwater plants. Being caught, this monitor
lizard is able to defend itself actively, biting by mouth full of rather large
needle-like sharp teeth.
Courtship season at this species takes place rather roughly, that is especially
remarkable for such cautious animal. Pairing is preceded with tournaments in
the water, accompanying with jumps and fountains of splashes. At this time
males chase and bite each other by mouth, trying slightly subsurface the contender,
showing the superiority. Loosed one stops resistance, having pressed paws to
sides, and when the competitor male lets it off, immediately retires.
Appreciating the origin, for egg laying this reptile comes out to land. Pike
monitor lizard is egg-laying reptile. In clutch it happens up to ten eggs by
size like small chicken ones. Females of this species dig eggs by back paws
in coastal ground above line of inflow. For breeding these monitor lizards
gather at small islands inaccessible to the majority of ground predators.
Nevertheless, the specific habit of life has already an effect for features
of breeding of these reptiles. Term of incubating of laid eggs at pike monitor
lizard is less, than at overland reptiles of the similar size. It is connected
with the feature of its development: development of embryo begins still long
before egg laying, in organism of mother. Pregnant females become inactive,
and spend more time in well warmed up gulfs. At this time they eat much less,
and frequently meet in groups up to ten reptiles and more.
Young pike monitor lizards, distinguishing from adults by brighter spotty colouring,
live in thickets of plants in shallow water, catching insects, larvae of fishes
and small frogs. They keep up-stream to avoid the possible attack of adult
reptiles of this species. Right after hatching the young growth aspires to
get in rivers, instinctively moving against current. The greatest mortality
among young animals is observed at this particular time: fishes and adult pike
monitor lizards attack young ones. Due to smaller weight young pike monitor
lizards move overland, passing through watersheds and settling in other rivers
easily. Adult reptiles are usually adhered to places of inhabiting though among
them there are some “tramps” overcoming even rather narrow sea passages between
islands.
It is possible, that in more long-term future descendants of this monitor lizard
may at all lose connection with land and pass to life in high sea, taken place
of dolphins and large predatory fishes in tropical seas of Earth.
This species was discovered by Arseny Zolotnikov
Underground
crown-tailed snake (Coronocauda caeca)
Order Squamates (Squamata), suborder Snakes (Srepentes)
Family Blind snakes (Typhlopidae)
Habitat: Hawaiian Islands, rainforests.
Hawaiian Islands are the land of volcanic origin separated from continents by
extensive water spaces. By virtue of reliable isolation on islands some groups
of animals typical for continents were abscent. So, at these islands there were
no ground tetrapods (except for birds): Pacific Ocean appeared practically insuperable
to them. But till the human colonisation of islands the situation had sharply
changed: similarly to many other islands, Hawaii became a shelter for set of
animals from various continents imported intentionally or casually. Their presence
had completely changed a direction of evolution of local flora and fauna, and
many species had completely disappeared. But nevertheless as a result in Neocene
at Hawaii the balanced but absolutely another ecosystem had generated, rather
than it could develop by natural way.
In the ground of Hawaiian rainforests the set of burrows forming extended circuits
is dug. They were dug out by local digging rodents, Hawaiian false mole rats,
similar to large-headed moles. In tunnels they are protected from ground predators,
but they never disappear from other creature also leading underground habit of
life. Pinkish body of this creature almost silently slides in tunnels of rodents,
and sharp sense of smell prompts this predator where it may search for holes
in which young rodents hide.
Tireless hunter for rodents, living at Hawaii, belongs to the primitivest snakes
on Earth – blind snakes. But by size this creature surpasses any of its continental
relatives – its length reaches one meter at thickness about 6 cm. Flattened head
of this snake is covered with thick corneous armour, and tail, on the contrary,
is obtuse. The tip of tail is topped with flat corneous “incrustation” with small
denticles at the edges, directed sideways and back. This formation looks similarly
to crown, and for that snake is named crown-tailed snake.
Present species of reptiles is the descendant of bramin’s blind snake (Typhlops
braminus) or “pottery snake” – small blind snake about 10 – 12 cm long, casually
introduced to Hawaii with indoor plants. At the islands this small creature had
received a fine food source as insects, including introduced ones. Its descendant
has reached length of one meter – millions years of evolution practically out
of competition had an effect. Large descendants of bramin’s blind snake passed
to feeding with small vertebrates including their own congeners. Gradually they
began to include in diet rodents digging in ground – descendants of mice introduced
to Hawaii. Underground crown-tailed snake became the largest digging creature
at islands.
Sight had not any significant role in life of ancestors of this creature, therefore
eyes of crown-tailed snake had completely disappeared, and even their seen traces
did not remain. Head of this reptile is covered with integral corneous shell,
becoming the fine instrument hole burrowing in wood ground. In behavior of blind
snake living under ground, colouring of body also does not matter, therefore
covers of body of this reptile became semi-translucent, pinkish-yellow. Skin
is covered with thin scales forming integral smooth cover. On the tip of tail
of snake the corneous scute with denticles sticking back on edges, similar to
crown, grows. This formation was developed as a support at movement under ground
– snake supporst by denticles against walls of hole. Usually crown-tailed snake
lives in holes of rodents, but easily burrows own holes in friable wood ground.
On ground surface this snake becomes absolutely helpless: crown-tailed snake
tries to find a point of support for tail to push and to burrow in the ground
again. Its muscles are very strong; therefore snake literally “dives” into the
ground and quickly digs in.
Crown-tailed snake has kept predating habits characteristic for all snakes. It
eats small rodents, Hawaiian false mole rats, chasing them in their own holes.
Keen chemical feeling helps crown-tailed snake to search for rodents by smell.
Teeth of this snake are sharp and recurved. Having grasped the catch, snake keeps
it in teeth while catch bleeds to death, and then swallows it. It equally easily
swallows catch both from head, and from tail.
Similarly to the majority of snakes the crown-tailed snake is oviparous species.
Once per half-year female lays up to five lengthened eggs covered with thin pergamen-like
shell. Males of this species may be met rather seldom. They are longer than females,
but differ in narrower head. Male finds female ready to pairing by the special
smell. For pairing snakes bury deeply in ground, and arrange under tree roots
the special hole ending by spherical chamber. In this chamber male and female
twist as if a knot, and spend some hours in such position while pairing lasts.
But as a rule, these snakes have parthenogenetic breeding without participation
of males. Stimulating the increase of hormonal level, females simulate pairing,
gathering by some individuals in the certain similarity of “marriage holes”.
Such behaviour promotes development of ovocites, and approximately after two
weeks females lay eggs. Female hides eggs in hole, digging it and stamping ground
by pushes of head.
Approximately in ten weeks from eggs young snakes hatch. They at once leave parental
holes and dig own burrows: adult snakes frequently eat their own posterity.
Young snakes become able to breeding at the age of about one year. First clutches
are parthenogenetic; completely advanced individuals pair with males and lay
normal eggs.
Atargatis
(Atargatis platicauda)
Order: Squamates (Squamata), suborder Snakes (Serpentes)
Family: Aquatic natricids (Aquanatricidae)
Habitat: southern part of Fourseas.
Fourseas, huge brackish lake in South-Eastern Europe, had appeared in Neocene
literally from non-existence. When climate began more humid, water had filled
hollows at the place of Black, Azov, Caspian and Aral seas, having formed common
midland reservoir. Sea animals could not occupy it: Mediterranean Sea nearest
to Fourseas had dried up, and because of increase of amount of rains in its
hollow the set of bitterly-salt swamps had appeared. Certainly, in such conditions
any sea animal could not survive physically. Therefore Fourseas was occupied
with rests of former fauna of Caspian and Black seas – fishes and invertebrates
had survived in salt lakes which existence was supported during ice age by
rivers of Eastern Europe.
The ichthyofauna of Fourseas is made basically by gobies and some other species
of fishes. But except for them in huge reservoir the set of various species
of vertebrates lives. In the sea-like lake there are even water snakes: it
is atargatis named after ancient Phoenician sea goddess.
By appearance atargatis resembles sea snakes dwelt in tropical seas in Holocene.
But those sea snakes lived on Earth in human epoch were poisonous representatives
of order belonging to separate family of sea snakes (Hydrophiidae), and atargatis
is the specialized descendant of colubrid snakes, having been classified, of
course, in independent family because of big differences in anatomy and habit
of life.
Atargatis is rather large snake: the length of its body is up to 3 meters;
the basic swimming organ, tail flatted from sides, accounts about half from
them. Up to tail body is cylindrical, slightly flattened at the stomach. The
skin is covered with homogeneous small scales, adjoining “end-to-end” and forming
smooth surface. Scale has “marble” grey pattern of irregular-shaped spots on
blue background, perfectly masking reptile in thickness of water. One detail
spoils this masking a little: on tail of snake there is oculate red spot with
white border – one from each side. This element of colouring plays double role:
during courtship season male (which is are longer and more harmonious than
female is) shows these spots to the female, and in case of danger spots, simulating
eyes, distract attention of predators from the true head.
Head of atargatis is flattened; at sight from above forward part of head is
rounded. In mouth of snake there is plenty of recurved teeth. This snake eats
fishes, killing them biting through head by teeth (poisonous glands at atargatis
are not present). The basic catch is fishes up to 30 cm long, usually small
and medium-sized gobies with cylindrical body. Also this snake willingly eats
crayfishes and large scuds. Due to rather thin forward part of body atargatis
can catch fishes and crayfishes even in holes. Usually this snake slowly swims
above thickets of water plants, from time to time putting out tongue. Due to
chemoreceptors atargatis catches chemical substances indicating presence of
fishes or crustaceans. Having caught presence of possible catch by smell, snake
starts to try water by tongue, shaking head in sides more often: it like scans
water, catching direction to source of smell. When the snake “detects” catch,
it bends tail S-shapely and makes throw by forward part of body, overtaking
prey. The lateral surface of tail serves to snake as support at throws to catch.
Atargatis kills prey not by poison, but by bite of long teeth. Snake tries
to seize fish by head and at once to bite through its skull, and seizes crayfishes
by armour from above (to avoid their pincers) and some time “chews” by jaws
to shatter its shell. Scuds having weak legs do not cause the big harm to snake:
at atargatis there is armored head. Snake swallows catch entirely: fishes are
swallowing from head (to avoid wounds by spikes), crayfishes and scuds, on
the contrary, from the part of abdomen.
Due to slow metabolism atargatis can hold breath at the whole hour, and even
prefers to sleep under water, having hided in thickets of plants in shallow
water.
This species of snakes had completely severed life on land, having reconstructed
breeding process. Even some species of sea snakes of Holocene epoch were compelled
to creep out on land to lay eggs. Atargatis had escaped of this difficulty:
it is ovoviviparous species.
The female ready to pairing emits in water odorous substance from cloacae glands.
Having felt it, males start to search and chase the female. During courtship
ritual male twists around of female, bites it by edge of mouth to the basis
of tail, pushes by head to surface of water. If near female at once some males
gather, they start to struggle with each other, twisting by bodies and trying
as it is possible to squeeze contender stronger. Only trembling of tips of
their tails indicates the huge effort to which there is a struggle. Usually
weaker contender, surrendering, starts to pull head in sides, trying to free.
In this case hard embraces are immediately unclenched, defeated male swims
away, and the winner starts to care at the female.
After long pregnancy (about half-year) the female gives rise to 2 – 3 rather
large youngs (up to 60 cm long). At the birthing moment each young reptile
is covered with thin membrane, and it immediately breaks it off by several
sharp movements. Having released from egg membrane, young snake emerges to
surface of water and makes the first breath. From the moment of birth it is
completely independent. First weeks youngs eat small fishes and large plankton
crustaceans. Sexual maturity at young snakes comes at the age of three years,
and life expectancy can reach 30 – 40 years and more.
Blind
cavesnake (Cavernerpeton caecus)
Order: Squamates (Squamata), suborder Snakes (Serpentes)
Family: Grass-snakes (Colubridae)
Habitat: caves in mountains of Central Africa.
Usually in caves rather small animals live: insects, spiders and other invertebrates.
More progressive animals, as a rule, do not belong to number of permanent inhabitants
of caves. Only in cave reservoirs there are fishes and amphibians. But in Neocene
mountains of Central Africa became the native place to one of most unusual
cave animals.
Food resources in caves of equatorial area differ in abundance in comparison
with those in temperate latitudes. The abundance of sunlight in equatorial
latitudes favors to growth of mosses and algae in caves even at significant
distance from an entrance. And such animals as bats and birds, settling in
caves, become a constant and reliable source of organic substances. Therefore
tropical caves have more various and numerous population.
In caves of mountains of Central Africa there is the original ecosystem including
different insects: beetles, cockroaches and larvae of different butterflies.
Some of them eat dung of bats, others gnaw seeds and sprouts of plants which
have got in cave in stomachs of bats. There are scavengers eating dead small
mammals, or tiny predators.
But all of them do not occupy top of feeding pyramid of caves: other predator
lives here. Between stones the long body of this rather large creature (its
length is about 1 meter) slides. It is covered with smooth shining scale, and
moves practically silently.
When the animal creeps out from stones to open place, it can be seen better.
It is a snake of ivory color with pale pattern like chain of yellowish spots
on back, with white stomach. The snake lifts head and then one feature of its
appearance at once is evident: it is blind. Eyes of this snake are latent under
skin, and scutes, closing eyes, differ from others practically with nothing.
The blind cavesnake – it is the name of this reptile.
The cavesnake never leaves underground world. Here it finds everything necessary
for life. The climate in cave is constant, here dangers of overheat or overcooling
are absent. Due to narrow body this snake easily squeezes even in “bottle-neck”,
therefore it in due course had widely settled in caves of Central Africa.
Sight at snakes has already undergone a partial degeneration when they passed
to partly underground habit of life during evolution. At the blind cavesnake
this process has gone even further, and there are only eye rudiments under
skin at this species. But instead of sight at this snake other feelings, senses
of smell and touch, are developed, permitting to receive the adequate information
about the world around.
Nostrils of blind cavesnake are well advanced and very large.
Because blind cavesnake is a predator, it lives only in caves where there are
colonies of bats. Cavesnake eats basically insects inhabiting such caves, but
also willingly eats fallen down cubs and weakened adult individuals of bats.
As against to many snakes, blind cavesnake eats carrion as willingly, as fresh
catch: food resources of caves are rather poor, and it is more favorable to
use them maximally full. Teeth of this reptile are numerous, but short, thin
and recurved.
Snakes are known for the ability to feel vibrations of ground, determining
in such way approaching of large animals or possible catch. Blind cavesnake
has unusually keenly advanced ability to feel vibration of objects. Due to
it this reptile it can feel the cockroach or cricket running on stone. During
hunting the snake constantly puts bottom jaw to stones or ground, determining
presence of moving catch. Snake makes solving throw completely blindly, having
found catch by speed and direction of movement. After throw the reptile promptly
rolls up to spiral, trying to “overflow” by loops of body environmental space,
and then compresses to dense knot. The sense of this tactics is, that even
if the insect at last moment will change movement direction, one of rings of
snake will necessarily cover and will press it down.
Cavesnake can not digest chitin of insects, therefore it from time to time
spits out the rigid armors of prey pressed to dense lump.
Despite of relative food abundance, each separate cave can support only limited
population of predators which stand at the top of feeding pyramid. But here
there is other problem: the population of snakes containing too little number
of breeding females, easily can degenerate. Therefore blind cavesnake during
process of evolution has got one more property: it became the hermaphrodite
from diecious animal. Sexual glands at this species had changed: one of them
became masculine, and another feminine one. Snake ready to pairing emits small
amount of odorous liquid, leaving appreciably smelling trace. By the same traces
left by other snakes, it finds partners for pairing.
During pairing two snakes mutually fertilize each other. Pregnancy lasts about
4 months. Blind cavesnake concerns to ovoviviparous species: each snake once
a year lays 5 - 7 large eggs covered with thin filmy shell, in which there
is already completely advanced posterity. Young snakes about 20 cm long hatch
from eggs practically at once. At them there is more contrast colouring, and
eyes appear under skin like dark spots. They can distinguish light and darkness,
and vaguely distinguish contours of subjects. After the first shed they start
to eat small insects, obviously preferring larvae of beetles and butterflies
with soft covers.
Young snakes can leave cave, and at night crawl out in searches of new places
of inhabiting. Thus they expand an area of species, and interfere with inbreeding
which leads to degeneration. Traveling snakes spend hot time of day in holes
of rodents or under stones. These snakes are guided, analyzing streams of air,
and finding wind carrying specific smells of caves. They grow slowly: sexual
maturity comes only at 6 - 7-years age at length of body up to 70 cm. But duration
of their life frequently exceeds 30 years.
Chameleon snake (Mutabilophis mutabilis)
Order: Squamates (Squamata), suborder Snakes (Serpentes)
Family: Grass-snakes (Colubridae)
Habitat: Japan Islands, humid tropical forests of south-east of islands, forest
canopy.
Snakes have very original evolutional history. In the beginning of formation
of this group of reptiles its early representatives passed to partly underground
habit of life; therefore their eyes had started to reduce partly. Further the
direction of evolution had changed: they had become active predators at the
ground surface again, and even had developed the world of forest crones. But
eyes earlier started to reduce had not restored to the full. At snakes cones
in eye retina are absent, and though some snakes have sharp sight, all their
species are not able to distinguish colors. Because of it snakes had lost many
features of behavior connected to the color signal system usual for lizards.
And one more feature of lizards had remained inaccessible to snakes of Holocene
epoch – they had not mastered the skill of color change for masking in environmental
district. At lizards of various species such ability was developed up to refinement
– in human epoch the word “chameleon” in some languages became the nominal
one, emphasizing variability of subject of conversation.
The world varies unpredictably, and the direction of evolution of any group
of live creatures can vary sharply. In this case attributes which gave advantage
earlier, may turn to serious difficulty. But occasionally evolution finds original
decisions for the similar problems formed at ancestors of evolving group in
connection with their further evolutionary history. In Neocene at Earth one
species of snakes able to change colouring partly – the chameleon snake – had
appeared. This reptile lives in Japan Islands, preferring warm rainforests.
Japanese chameleon snake has kept habitual shape of snakes. It is rather massive
reptile about 2 meters long with flattened body. It spends practically all
life in tree crones where it eats birds, wood mammals, amphibians and even
large insects. The chameleon snake prefers to swarm up thick branches and trees
trunks, and is also sluggish reptile.
At this reptile there is large head with expressed cervical interception. Chameleon
snake is not poisonous, but its teeth are numerous, sharp and slightly bent.
Slow moving does not prevent this snake to hunt successfully because it is
compensated by the most remarkable feature of chameleon snake – the ability
of color change. The mechanism of this phenomenon permits to bypass such lack,
as absence of color sight. Abdominal scutes of this snake are connected to
numerous receptors, and allow the reptile to define features of surface on
which it creeps. According to these sensations color of skin of the snake varies.
Sight of all snakes is bad, therefore chameleon snake is not able to estimate
precisely color of objects among which it moves. The mechanism of color change
at chameleon snake is very approximate; it is based at the estimation of contrast
of environmental district and character of tactile sensations. At chameleon
snake there are few variants of colouring, connected with certain tactile sensations,
and this reptile can change color only in these rigidly determined limits.
On rough bark snake gets brownish color with longitudinal wavy strips. Among
smooth leaves the chameleon snake becomes spotty – on green background black
spots appear. At night colouring of the reptile darkens, and at the bright
sun it turns lighter.
Scales on the top side of body of this reptile are small and transparent. On
skin chromatophores are placed, due to which contraction and expansion this
reptile can change color. The stomach of this snake does not change color –
it is white; on throat and neck there are black spots.
The chameleon snake lives in wood crones, only occasionally creeping down to
the ground. Usually snakes living on trees are thin and mobile. But this species
is massive reptile not able to chase catch for a long time. This snake can
make only short throws for catch, therefore it prefers to expect while catch
will approach to it itself closely. The chameleon snake suits ambush on branches,
using its ability to change color. Usually it nestles against the bark or hides
among moss and foliage. The reptile kills catch with the help of teeth, not
strangling it like boas or other snakes.
In courtship season males actively search for females, defining their presence
by smell. The male ready to pairing changes color: it becomes black with white
stomach and separate white spots on body. The male shows to the female the
throat, lifting head upwards at the right angle to body. If two males meet
near the female, they try to push each other away from it, striking the contender
impacts by lateral face of head. Fights of males in courtship season resemble
the competition of heavyweight wrestlers – it is more force struggle, rather
than effective demonstrations. Sometimes one of males may simply “bind” the
contender by rings of body to the branch and show to the female readiness for
pairing, physically keeping the contender. Recognizing defeat in courtship
duel, the contender strongly turns pale, becoming almost completely white.
Then won male lets the contender off.
The female turns pale only a little, admitting the male to pairing. Pairing
occurs in tree-trunk hollow and may last some hours in succession.
The chameleon snake belongs to oviparous reptiles. The female is compelled
to creep down to the ground to lay eggs. It cautiously creeps down the trunk,
clinging by scutes tor roughnesses of bark. On the ground the female finds
a secluded place (frequently right among roots of tree on which it lives),
and lays to simple small hole in the ground some tens of eggs. Having dug eggs,
snake comes back to the tree crone and does not care any more of posterity.
The incubating of eggs lasts about 55 – 60 days. Length of just hatched chameleon
snake is about 20 cm. At young snakes ability to change color is less advanced.
They are green with brown irregular-shaped dabs and live in bush and among
young trees. Later, having had reached the length about half meter, young chameleon
snake gets ability to change color and moves to the tree crone.
Hopping tree snake (Trachygasterophis saltatus)
Order: Squamates (Squamata), suborder Snakes (Serpentes)
Family: Grass-snakes (Colubridae)
Habitat: Japan, rainforests.
Japan islands are the volcanic ridge in the place where the bottom of Pacific
Ocean “dives” under the continental plate. Pacific Ocean renders enormous influence
to the climate of this region. In Neocene, when the climate of islands became
warmer and more humid, southern islands of archipelago had become covered by
rich rainforest. This forest is rich in various lifeforms, among which extermely
specialized ones frequently live.
The canopy of Japan rainforests is strongly close and bound by lianas: it is
an adaptation for survival in conditions of often hurricanes blowing from Pacific
Ocean. It represents very favorable inhabitancy for species of tree-climbing
animals. Some of them never go down to the ground.
Among inhabitants of forest canopy there is a lot of climbing mammal and reptiles.
And one of the most interesting snakes of the world lives in rainforests of
Japan – it is the hopping tree snake. It is the reptile up to three meters
long with very thin body and long tenacious tail (its length amounts more than
half of general length of the reptile).
The hopping tree snake has cryptic colouring: top of its body is green, bottom
is brown, and lines of short slanting strokes of black color pass on sides.
This reptile eats mainly small birds, showing the big dexterity in hunting.
It seizes them hurriedly, at throw clinging for branch only by tail. In some
cases it rushes on birds, completely coming off from branches and catching
prey in flight. Having caught prey in air, the reptile falls back in branches,
and manages to seize branch by tail in falling. In dexterity of movement in
branches it does not concede to monkeys.
Eyes of this snake are rather large and also shifted to the forward part of
head. They provide practically three-dimensional sight that is very important
at an estimation of distance to catch or next branch. In retina there is lack
of cones (it is usual attribute of all snakes), but by density of rods the
retina of this snake is comparable to retina of nocturnal mammals. Pupil is
chinky, longitudinal, with small expansions on edges. It results to that in
eye of hopping tree snake two areas of the best perception are present: one
of them is formed by first line of pupil and helps to consider catch and to
estimate the distance, and the second one, perceiving images transmitted from
back edge of pupil, provides the snake good lateral sight. Having slightly
turned head, snake can look objects behind its head.
The tail of hopping tree snake is very strong and tenacious, it is easily bent
in any side, and vertebrae can even turn a little about the axis. On the bottom
side of tail corneous scutes have small spike-like outgrowths on edges assisting
to fix in throw. Scutes on the bottom side of tail also can rise with the help
of special muscles, improving durability of branch capture.
To lead such way of life, it is not enough only to have tenacious tail. Wood
mammal and lizards, jumping from branch to branch, amortize inevitable pushes
by paws, and their internals do not feel impacts. At the hopping tree snake
paws are not present, and it must accept impact against the branch by all body.
To not injure internals this reptile had got additional protection. Abdominal
scutes at this species of snakes are firm and elastic; at impact against the
branch they spring, protecting internals of snake from traumas. The snake weighs
a little; therefore corneous scutes protect its interiors well.
Ribs of hopping tree snake also had changed a little: they cover internals
from sides, and their tips are connected by extensible sheaf, also amortizing
at impact. Such additional protection has imposed the certain restrictions
to the diet of hopping tree snake. Usually snakes eat rather large catch which
can be larger than diameter of their body. When the usual snake swallows catch,
its internals and muscles stretch strongly. The hopping tree snake does not
presume to itself such diet because of ligaments between ribs and strong abdominal
scutes. It eats only small birds, and even attacks large insects: it eats butterflies
and big caterpillars. But the thin body and ability to jumps allow this reptile
to eat nestlings of small birds nesting in narrow tree-trunk hollows or attaching
nests to tips of thin twigs. Food specialization of this reptile is rather
strict; therefore hopping tree snakes are territorial very much. Each reptile
marks borders of hunting site by secretions of glands located near cloaca,
and does not tolerate strangers at its territory.
hopping tree snake is very much specialized to tree climbing. It spends all
life in forest canopy, never creeping down to the ground. This reptile prefers
to live in old woods with rich canopy interwined with lianas. This specialization
considerably limits opportunities of its settling; therefore the distribution
of this species is limited only to sites of rainforest at the south-east of
Japan Islands.
Pairing of these reptiles occurs unusually: male and female weave together,
hanging on tails under tree branch. Frequently pairing takes place at height
up to 30 – 40 meters on branch shaken in wind, but it does not frighten reptiles:
in such place they are perfectly protected from the majority of predators.
Only predatory birds can attack them at this moment. They are main enemies
of hopping tree snake.
The female in which ovaries eggs are forming, becomes less mobile and more
cautious. It prefers to hunt on branches and does not make risky jumps for
catch. Fertility of hopping tree snake is small, and does not exceed 5 lengthened
eggs in one clutch, but the egg laying may repeat each month. This reptile
lays eggs in tree-trunk hollows, burying them in dust at the bottom of hollow.
Frequently the female makes some clutches in same tree-trunk hollow, and at
the bottom of such hollow there are simultaneously egg shells, eggs at various
stages of incubating, and young snakes.
Young snakes hatch after 6 – 7 weeks of egg laying. Young snakes are colored
green with white stomach. They become sexual matured at three-year age.
Lancing snake (Hastatoserpenta sylvatica)
Order: Squamates (Squamata), suborder Snakes (Serpentes)
Family: Grass-snakes (Colubridae)
Habitat: Eastern Madagascar, a rain tropical wood.
Tropical regions of Earth differ in surprising variety of reptiles, among which
there are numerous snakes. Till the ice age at the boundary of Holocene and
Neocene many species of these reptiles had died out, as the area of rainforests
had strongly reduced. But in Neocene changes of climate had resulted in expansion
of the area of tropical forests, and as the consequence to the increasing of
number and variety of snakes. Some of them had got new features of behavior
which had not been present earlier.
In rainforests of Eastern Madagascar there is one interesting species of forest
snakes. It is usual medium-sized reptile – its length is no more one and half
meters, and its body is thin. This snake has brownish-grey color, masking it
on the background of wood bark. Its body is covered with irregular mesh pattern
imitating wood bark, and on head from above there is a yellowish-white spot.
This reptile lives in tropical woods of Madagascar, equally well feeling like
on trees and in wood litter.
This snake is really surprising. The descendant of Madagascar leaf-nosed snake
(Langaha madagascariensis), the lancing snake differs in interesting way of
food getting. The matter is that the nose of this snake, both at males and
at females, terminates by long narrowed edge. This outgrowth is approximately
equal the other part of head of the snake; it is very durable, and also is
sharp: it is formed by lengthened and partly grown together bones of skull
covered with dense ridge scales. Hence this snake has received the name “lancing
snake”. This reptile differs in inactive way of life, and usually expects catch,
having hidden on branch. Thus colouring of its body merges with texture of
bark, and head precisely simulates the broken bough with light wood. As soon
as it notices any potential prey (large wood frog, bird or rodent), it makes
flash-like strike by head, piercing prey by nasal outgrowth, as if by dagger.
Having struck prey, snake at once pulls out the killing instrument from the
wound. “Dagger-like” impact lasts only a split second. If the prey was not
killed at once and had managed to escape, it dies later from loss of blood
and damage of internals. The snake simply finds it by smell and swallows entirely,
as well as it is characteristic for all snakes. It may happen that catch will
remain pined on snake’s nose, especially when it is small creature. In this
case lancing snake removes prey from nose, having griped it in rings of body.
One more interesting feature of the lancing snake is the structure of its tongue:
on its tip there is the fleshy pillow, serving to clear eyes and head of blood.
At the attack of large animal lancing snake can use rostrum as means of protection:
it puts painful wounds to nose and eyes of aggressor. The similar way of protection
is developed at snake of other species living in savannas of North Africa –
egg drillsnake (Ovisugerpeton ovisugus). But it strikes impacts to the enemy
not by rostrum, but by strong teeth sticking forward.
It is the oviparous snake breeding at any time of year. Eggs in amount of 10
– 15 ones are layed in ground, and the female does not care of clutch protection.
Strong rostrum helps to young snakes to punch skinny egg shell, but it is too
short to be used as the hunting weapon. Small lancing snakes first time catch
insects and tiny vertebrates, biting them by teeth. But at them the spike develops
rather quickly, helping to hunt the same way, as it is done by the adult reptiles.
The closely related species of snakes lives in rivers of Eastern Madagascar:
the river
lancing snake, or the harpoon snake (Potamohasta ichthyophaga).
It is similar to the wood relative, but differs a little in colouring and the
body shape. Top of body at this snake is silver-grey and stomach is milky-white.
Body of this reptile in back part is rather wide and massive, and head and
forward third of body are thin. It eats fish (preferring small fishes with
long and not deep body) and water frogs, killing catch the same way as its
forest “cousine”. Thus the wide body serves as a support for snake at the rush.
Harpoon snake often hides among driftwood and water plants, and even is
dug by tail in river bottom. Being externally similar to sea snakes of Holocene,
this reptile is not as specialized, as they were: it can creep on land, easily
crosses marshy sites of wood, and besides lays eggs in ground.
These species of reptiles are discovered by Simon, the forum member.
Dwarf vinegar snake (Acetophis foetidissimus)
Order: Squamates (Squamata), suborder Snakes (Serpentes)
Family: Grass-snakes (Colubridae)
Habitat: Japan Islands, humid forests at the southeast of archipelago.
Snakes are youngest groups of reptiles existing in a Neocene. Having evolved
in cretaceous period, they had kept rather monotonous and recognizeable shape,
and differ only by some features of anatomy. In human epoch basically large
or local species of snakes had died out – mainly because of destruction of
habitats, and partly because of hunting. But smaller snakes frequently adapted
to life in the neighbourhood with people and found rich prey as rodents and
small birds, and in tropics more lizards and large insects besides of them.
One small insectivorous snake of Neocene lives in tropical forests at the southeast
of Japan Islands. It is dwarf vinegar snake, the only representative of genus
endemic for Japan Islands, harmless reptile which spends the most part of
time, creeping in forest litter and searching for prey. It feeds exclusively
on insects
(preferring soft-bodied cockroaches and grubs) and slugs. Body length of dwarf
vinegar snake is about 40 cm. It has rounded head, cylindrical body and very
short tail.
Appearance of this snake is very bright and well-remembered. It imitates very
precisely tiger millipede – a kind of poisonous millipeds living in the same
place. Colouring of body of this snake is orange with black cross strips. The
tip of muzzle of snake is black (it is an imitation of head of millipede),
and eye is masked by black vertical strip. Edges of belly plates are white
with black border – they imitate legs of millipede. Usually dwarf vinegar snake
tries to hide in depth of leaf litter in order to avoid meeting with possible
predators. The disturbed snake imitates a way of protection of milliped – it
rolls in spiral and hides head among coils of body. Also it imitates smell
of protecting milliped, emitting from cloaca an odorous liquid having vinegar
smell and unpleasant bitter taste. But, as against to tiger millipede, this
species is absolutely poisonless. The only active protection of which this
snake is capable is a bite of pointed teeth. It may be enough to support warning
colouring which it has.
Due to warm climate these snakes are active the year round. Dwarf vinegar snake
searches for food from midday till evening, and in the rest of the time it
prefers to stay in shelter, having turned to spiral like a protective pose
of milliped.
Seasonal prevalence in breeding at this species is not expressed. Male differs
from female in a little bit longer tail and thinner body (it weighs less, rather
than female at equal body length). Male searches for the female ready to pairing
with the help of smell sence. Pairing takes place at night in shelter, where
the female is usually hidden.
Dwarf vinegar snake is ovoviviparous and differs in very low fertility – in
ovoduct of the female no more than two eggs in thin leathery pellicle are incubating
simultaneously. Their development lasts till about 4 months. The female bears
posterity two times within one year. Young snakes leave egg covers right at
birth. The length of young snake makes almost half of length of the parent.
Young snakes of this species frequently search for carrion or dung of large
mammals, and eat larvae of flies developing in such substratum. They reach
length of adult individuals in three years, and one more year later become
able to breeding.
Saw-nosed
crocodile (Pristisuchus serratorostris)
Order: Crocodiles (Crocodilia)
Family: Saw-nosed crocodiles (Pristisuchidae)

Habitat: brackish sea gulfs, mouths of rivers of South-Eastern Asia, Indonesia,
Australian-New Guinean continent (it is especially numerous in Arafura Lake).
In warmed up extensive shallow freshened coastal lagoons of coast of South-Eastern
Asia life boils over. Here it is a lot of forage, algae, plankton; it ideal
place for feeding and fatting. Besides water has the lowered salinity that
reduces expenses of forces to osmotic regulation. Here numerous oceanic fishes
come to food up. They frequently swim in big dense shoals, relying to the best
passive protection by the large number. It is meaningful frequently, but not
always. Suddenly narrow long shadow runs into such dense shoal. Narrow long
flat “saber”, armed at edges by big sharp thorns, starts operate barbarously
here and there, harming strongly incautious fishes. In shoal the panic begins.
The density of the fish shoal plays not on a hand to its members; they rush,
come across against each other, are thrown here and there and in larger number
get under ruthless impact of terrible weapon. Eventually the shoal blurs in
sides, leaving about ten twitching, bleeding profusely, and crippled fishes.
Predator quietly begins meal.
It is the saw-nosed crocodile growing up to length up to 3 m. It is one of
few species of crocodiles had survived up to this time. It is very much specialized
one and it seems similar to gavial. But gavial had died out, not having left
descendants: its number was decreased by people, and specialization did not
promote a survival in epoch of mass extinction. The saw-nosed crocodile descends
from any Asian species of crocodiles had survived in epoch of global cataclysms.
Other species of crocodiles, the furious sharkodile,
lives in tropics of Pacific Ocean. In the majority of tropical rivers the place
of water predator was occupied by fishes (up to sharks!) and lizards. Therefore
the saw-nosed crocodile lives any more not in rivers, but at the coast of sea
lagoons where there are more fish frequently keeping in dense shoals.
It is perfectly adapted to feeding by fishes. At this reptile there are narrow
graceful body, wide tail and extended narrow jaws. Long teeth at its long and
sword-shaped top jaw grow originally: they are directed perpendicularly sideways.
As a result the “saw” is formed like existing at Holocene saw-fishes one. It
also operates by this saw in shoal of fishes, having rushed into its thicket
and making sharp jerks by head here and there, horizontally and aslantly. The
small part of teeth of usual shape and smaller by size, is visible in intervals
between “saws jags” and serves for capture of catch. On the bottom jaw all
teeth are small and “standard”. During hunting jaws are closed, and resistance
of water is minimal. The body of this crocodile is not covered any more by
heavy osseous armour as at its far ancestors, it is not necessary any more
to this species to protect intensively, it is more necessary to have speed
and maneuverability. This reptile is covered with strong elastic skin. Rudiments
of armour are submitted partly by back and occipital scutes. The skin has greenish-grey
color with fuzzy cross-striped pattern and lighter belly, masking it in a thickness
of water have been lit up by solar patches of light in shallow water. Its paws
are weaker, than at ancestors, and it never leaves far from water. But a lot
of time it spends in water, but quite often it can be seen at the coast where
it is basking at sunny place. Especially numerous groups of crocodiles of this
species gather at sandy shallows in river estuaries.
Having got warm, crocodile starts to hunt, making the way to water along fenny
marshy coast. Its paws are weak, and frequently the animal simply slides on
dirt on stomach, pushing by them. It quickly and dexterously swims, using rather
wide powerful tail. In the beginning, having noticed suitable fish shoal, it
imperceptibly creeps to fishes, then as the knife, promptly runs into it and
swings the weapon. Having sated, the reptile creeps out to the coast and has
solar baths. The terrible blow of jaws armed with sharp teeth and a powerful
tail waits predator dared to interrupt its rest. However large or pack predators
occasionally nevertheless manage to win it, because paws of the crocodile are
not such powerful, and skin is not so is strong as at crocodiles of Holocene.
It breeds like all crocodiles: the female lays eggs in nest dug on coast in
silt and grass, and protects posterity. Young ones feed in shallow water in
thickets, mainly with medium-sized fishes, and eat as usual crocodiles; they
start to master the characteristic habit of hunting at the age of three years.
In early age they can become chase of predators.
Adult individuals are territorial; they supervise sites at the coast do not
supposing contenders. However this division is indistinct as at the seal rookery,
and each time it is made anew in process of returning animals from fishing.
Sorting out of relationships is usually strictly ritualized, and is limited
to that contenders raise upwards the top jaw, looking who is larger.
During courtship fights males are not so ceremonious, and easily can put to
each other an injury by “saws” armed with teeth, when swing them before the
contender, and quite often impacts strikes.
The life duration may account about 70 years.
Amphibians
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Cave
wormsalamander (Typhlodraco branchiatus)
Order: Tailed amphibians (Caudata)
Family: Salamanders (Salamandridae)
Habitat: caves of Balkan and Near East.
Caves are specific habitat. The cave environment substantially differs from
surface of the ground. Here there is no light; therefore biological efficiency
of caves is very low: plants practically do not grow here. Only bacteria can
provide food needs of inhabitants of caves in any degree. The majority of food
chains of cave ecosystems stretches to the ground surface. Bats, birds and
insects deliver to caves organic substances from world around which animals,
never seeing sunlight, eat. Also organic substances can get in caves at river
floods.
But caves differ in stability of conditions of inhabiting: here daily and seasonal
fluctuations of temperatures are practically not felt, and humidity of air
is constant and close to 100 %. Not all live creatures can adapt for life in
conditions of eternal darkness, but nevertheless caves are plentifully inhabited.
Amphibians are largest inhabitants of these places in Europe.
In caves frequently there are reservoirs settled by various live creatures.
Usually there are worms, small crustaceans and fishes in them. Their food includes
rests of plants and the dead animals delivered by water. But above them the
predator reigns, crowning feeding pyramid of caves.
In rivers flowing from Balkan caves, it is possible to find unusual animals.
They swim like small fishes, but their body is covered with naked skin, and
on each side of heads three pairs of soft feather-like pinkish gills stick
up. But at them even a rest of legs is not present, and eyes are closed by
transparent thin skin. Bodies of these creatures are delicate, and through
skin on the belly interiors appear through. They obviously are larvae of any
amphibians.
The river has taken out young growth to the surface, but their parents have
remained in gloomy world of cave. Here, in outer darkness, they search for
livelihood - other inhabitants of cave rivers. Naturally, these creatures are
larger than larvae meeting at the surface. Their bodies are pale, and eyes
completely are absent. Only two stains indicate their past site on head. Parents
are as poorly similar to any adult amphibian, as their posterity.
The inhabitant of caves, the cave wormsalamander is neotenic larva of one of
salamander species dwelt once at the ground surface. Escaping from climate
cooling and drying in ice age, ancestors of these animals have receded in damp
caves. Life in gloom has left traces at shape of these animals, having transformed
them to underdeveloped, but nevertheless adult larvae.
The cave wormsalamander is legless worm-like animal about 40 cm long. About
40 % of length of animal tail accounts. At this amphibian there is delicate
translucent skin of rosy-white color through which interiors appear through.
But at animals living in caves where the sunlight gets, pigmentation of skin
develops: small white spots on brown background. This animal spends all life
in water, therefore at it there is mainly branchial breath with the help of
three pairs of external feather-like gills. Because of them this animal resembles
by something fantastic dragons (the name of animal means “blind dragon”), invented
by people which had missed long time ago. But by properties it is rather far
from frightening prototypes.
At the wormsalamander also underdeveloped lungs have remained, and the animal
from time to time emerges to surface of water, swallowing a portion of air
with silent smacking sound. Air in lungs serves this amphibian as certain analogue
of swimming bladder, helping to remain swimming.
In darkness of cave sight is not necessary, therefore the wormsalamander is
completely blind. But instead of sight at it other sensor organs are advanced.
At the wormsalamander the lateral line, detecting vibrations of water, proceeding
from swimming or creeping live creatures, is well advanced. Also it has bodies
of electric feeling allowing more precisely to determine presence of live creatures.
The tail is bordered from above and from below by fin plica.
The male is larger than the female; at him tail is longer, making up to half
of general length of animal. Ritual of courtship is reduced to some necessary
actions: male finds female by smell, catches her up and snaps by tail fin.
Twisting around of body of female, male keeps her, and begins courtships. He
swims around the female, rubbing by throat against her body, and from time
to time pushing her by head. When courtship ritual reaches apogee, male emits
spermatophores on stones.
Wormsalamander is a live-bearing amphibian; in oviducts of female within 3
months after fertilization only two larvae about 10 cm long develop. They are
a little more advanced, than adult amphibian of this species: at them eyes
covered with thin translucent skin are more advanced.
Larvae can distinguish light and darkness, and vaguely distinguish contours
of subjects. They have very important role in life cycle of this species, settling
from one cave to another through reservoirs at the ground surface. Usually
it happens during rain season when underground rivers overflow with water and
leave on surface.
Similarly to all representatives of amphibians, the cave wormsalamander is
a predator. It eats any live creatures which can find in caves: fry, small
crustaceans, and sometimes even its own posterity. Metabolism at this animal
is very slow, and after plentiful meal the wormsalamander may desist from eat
about one month.
Monsternewt (Siluroherpeton cryophilus)
Order: Tailed amphibians (Caudata)
Family: Swampers (Pseudoandriidae)
Habitat: Northern Europe up to Ural, Scandinavia.
After human extinction till millions years the Earth had gradually cleared
of various kinds of pollution left by this species. Polluting and poisonous
substances had been gradually decomposed as a result of activity of bacteria
and other organisms. Chemical elements making them had included natural geochemical
cycles, and in Neocene epoch the planet had returned to protogenic cleanliness
in ecosystems.
In human epoch the species sensitive to pollution of environment died out or
receded from places where people conducted economic activities. Among them
there were especially many species of fishes and amphibious. Human extinction
had permitted to evolve to new species of these animals, exacting to cleanliness
of inhabitancy.
The territory of Europe had strongly suffered from human activity, and a number
of species of amphibians lived there became rarity. The glaciers came from
the north, had almost completely destroyed marks of presence of people in this
part of the world. When people had died out, amphibians had returned to themselves
primordial habitats and evolved to strange and unusual species.
In head waters of rivers of Europe running into Arctic Ocean at the north,
and into Fourseas at the south, the largest European species of amphibians,
the monsternewt, is found. It is the close relative of Siberian glutton
swamper (Pseudoandrias silurops) which is the largest species of amphibians
in Neocene world.
Monsternewt considerably concedes in size and weight to glutton swamper, but
is also a large amphibian. Body length of this amphibian is about one meter
including tail. At monsternewt there are large head, wide body, deep tail with
fin plica stretched up to middle of back, and strong paws without claws. This
amphibian has soft dark brown skin with small darker spots, lighter bottom
side of body. On stomach skin forms the set of longitudinal plicas taking part
in skin breath. Also at this animal branchiate apertures are advanced and there
are small external gills.
Monsternewt is inactive ambush predator and is not able to chase prey at long
distance. This amphibian waits for prey, having hidden among water plants,
or having slightly dug in silt. It has flat head with wide mouth and strong
jaws. Teeth of this animal are tiny; they serve only for keeping of rather
small prey – frogs, crayfishes, fish, mammals and small aquatic birds. Eyes
at this amphibian are extremely small, located on edges of head near corners
of mouth. Bodies of lateral line play the vital role in life of monsternewt
– they form a dense system of sensitive channels on head of animal, and stretch
as double line along each side. With their help animal can define the location
of prey even in complete darkness. These animals well feel like in karstic
caves.
Monsternewt lives in cold water containing a plenty of oxygen and because of
it is intolerant to overheat of water. The greatest number of these amphibians
lives in rivers and lakes at the north of Eurasia. The period of maximal activity
of monsternewt falls to the time of high water. At this time amphibians settle
to new habitats, especially if favorable habitats are overpopulated. In high
water young individuals frequently meet in forest, and appear in traps – in
small isolated ponds, whence they can not get out. This amphibian can not move
overland – on air wet skin of animal dries up quickly, and monsternewt chokes.
In summer monsternewt is inactive and hides in deep cold whirlpools where underwater
springs gush out. In winter this amphibian creeps on the bottom under ice and
hunts on fishes wintering in underwater holes. Animals from cold river heads
and karstic reservoirs keep activity even in the middle of summer. In winter
at complete freezing of shallow-water reservoir monsternewt digs in silt and
falls into catalepsy. When ice thaws, it continues habitual life.
In early spring monsternewts spawn. Spawning begins when rivers free from ice
and the time of high water begins. At the male during the spawning time colouring
becomes much brighter. It has bright orange-red color of stomach. Courtship
dress of the male also includes high skin crest on back and rounded “horns”
above eyes. During the spawning males “butt” for females, pushing away each
other by heads. Also with the help of “horns” male pushes female to spawning
place – to thickets of underwater vegetation. Clutch of monsternewt is rather
large – it numbers over 10 thousand eggs strongly swelling in water and covering
with the common slime cover. The incubation lasts till about one month. From
eggs long-bodied legless larvae with well advanced plumose gills hatch. They
lead predatory habit of life, and for them cannibalism is very characteristic.
As against to adult monsternewts, larvae well enough exist at higher temperature.
Till the summer they manage to grow up to 10 cm, and legs develop at them.
Since the second year of life young animals gradually start to avoid the high
temperature, and pass to autumnal, winter and spring activity.
The sexual maturity at monsternewt comes at fifth year of life. Life expectancy
of this amphibian is not less than hundred years.
“Termite queen” (Batrachoregina hygrophila)
Order: Tailless amphibians (Anura)
Family: Narrow-mouthed toads (Microhylidae)
Habitat: South Africa, dry savanna.
Amphibious are the primal vertebrate land inhabitants. They had not completely
left the water environment – water is vital for them in spawning season, and
the majority of amphibians prefers to live in wet places. But despite of such
vital requirements these animals had managed to adapt even to inhabiting in
arid areas. Though Neocene differs from Holocene in more humid and warm climate,
deserts and savannas cover a significant part of planet. One of such places
is South Africa. Sometimes it is too hard to find water here, and termites,
which are very moisture-loving insects, are compelled to dig deep vertical
shafts, reaching up to aquiferous stratum. And various animals searching for
moisture and safety willingly use their constructions. It is difficult to not
cause aggression of furious termites from soldier caste, but nevertheless in
buildings of termites the set of various animals lives. Basically there are
insects among them, and occasionally millipeds and spiders are. But one of
large “guests” of termites is the strange big-bellied frog about 8 centimeters
long. It behaves rather confidently and feels like in the full safety, surrounded
by insects equipped with protective weapon. In dry season this frog meets only
in constructions of termites. For these features it has received the name “termite
queen”.
The secret of loyal relation of termites to their “queen” is contained in chemical
substances secreting with slime of “termite queen”. Skin secretion of this
frog reduces aggression of termites. These insects perceive this frog almost
like their relative: they lick secretions of skin of “termite queen”, and do
not attack her, even when the frog eats several termites one by one.
“Termite queen” has short and thick, almost spherical body with rather short
paws. This frog is not able to jump, and moves on the ground, walking like
a toad. Skin of “termite queen” is smooth with strongly advanced skin glands
producing secretions attractive to termites. Its colouring is dusky – grayish-brown
with small dark spots at the top part of body; stomach is white. Head of this
frog is short and wide; eyes are small, protected from stings of termites by
transparent eyelid. “Termite queen” has bad developed sight sense – it spends
the most part of life in complete darkness of galleries of termitary, and appears
at the ground surface only at night during the rain season. But this animal
orientates very well in termitary due to sense of smell and advanced touch
sense.
This frog is adapted to digging habit of life. On its paws large corneous callouses
develop on external edge of foot and forearm. It digs holes in the basis of
termitary and frequently uses ready galleries of termites for movement. The
similar way of life is led by desert mole toad (Cryptophrys
cornicephalus),
living in Meganesia; it is an example of the convergence, because the species
from Meganesia belongs to another family.
“Termite queen” eats termites and other insects living in termitaries. It obviously
prefers large insects – crickets and cockroaches, and also adult termites.
But in each termitary only one or two adult frogs of this species live (and
also some small not sexually mature individuals may exist near them), therefore
damage put by such “queen” to the colony of termites is small. Even more so,
it eats various symbiotes and parasites of colony of termites more often, than
termites.
This frog spawns during short rain season. When it feels that the ground becomes
wetter, it leaves termitary using galleries, and digs a tunnel to the ground
surface. Having reached a surface, frog gets out of hole not at once – it makes
it only when night comes. At this time tens of “termite queens” hasten to temporary
reservoirs to spawn. Males get out on surface earlier, than females. They share
coastal sites of reservoir to set of territories, and involve females with
the help of call similar to long descending whistle. In day time males prefer
to dig in ground on coast of reservoir, or hide in thickets of marsh plants.
Females creep to the surface later. Within one night pairs form, frogs spawn
and immediately leave a reservoir, coming back to the same places where they
lived before. “Termite queen” is never mistaken, returning after spawning only
to the same termitary. At the second night only separate females come to reservoirs,
and third spawning night, as a rule, does not come.
In clutch of these frogs it is totaled up to 300 eggs stuck to one mucous ball.
Tadpoles of these frogs in the beginning eat algae, and from 9 - 10-day’s age
become predators and cannibals. Up to the metamorphosis (at the age of 45 –
50 days) no more than 10% of the general number of tadpoles survives. Young
frogs dig in ground and search for galleries of termites along which they reach
dwellings of these insects. The part of frogs perishes from stings of termites
– not all species of these insects accept such “visitors” peacefully. But the
frog managed to lodge at termites of suitable species can live about ten years.
Motley midgefrog (Miniranula multicolor)
Order: Tailless amphibians (Anura)
Family: True frogs (Ranidae)
Habitat: Western Siberia, swamps and marshy forests.
Significant territories of Eurasia differ in rigorous continental climate,
and this circumstance does not favour to settling of amphibians and reptiles
there. Only few species of these animals had adapted to seasonal climate. Those
species which could make it had developed various adaptations, permitting to
resist to the most terrible enemy – to winter cold.
When swamps and lakes of Western Siberia release from ice cover, it is possible
to see various aquatic animals in pieces of ice floating on surface of reservoirs.
Some of them had got in ice casually and lost, and others normally endure such
test and after will thaw, continue the habitual life. In ice captivity there
are larvae of various insects, small crustaceans and their eggs, and also small
long-bodied creatures similar to thin transparent fishes. They are tadpoles
of local midgefrogs – animals prospering in Siberian climate. They are alive,
though are frozen, and simply wait while warmth of sun will release them. But
in ice there are only separate tadpoles had got there casually. The much greater
number of tadpoles is hidden in layer of silt at the bottom of reservoir. When
ice starts thawing, their multithousand shoals leave the refuges and gather
at warmed up shoalinesses. Jaws of midgefrog tadpoles are scraping – with their
help they gather algal scurf from the surface of plants and eat tiny sedentary
animals. One of the main enemies of midgefrog tadpoles is giant
bladderwort,
carnivorous aquatic plant.
One of the most terrible inhabitants of Siberia are not predators, but numerous
blood-sucking insects. Their larvae successfully survive in winter and from
the beginning of summer there is their mass metamorphosis to adult mosquitoes
and midges. These insects do not give rest to mammals and birds – they attack
by whole flights during all night and the most part of day. But just at the
moment of their metamorphosis tadpoles also turn to frogs, and adult individuals
of midgefrogs appear provided with food of suitable size.
Adult midgefrogs are very tiny creatures. The length of normally advanced individual
at all species of this genus does not exceed 20 – 25 millimeters (male is smaller,
than female). They are reliably protected from predators by strong poison which
contains in their slime. During the evolution at midgefrogs bright warning
colouring had developed. Many species of this genus of frogs distinguishing
in ecology and well distinct on features of colouring live in Siberia. All
species of these amphibians are able to climb dexterously on branches of bushes
and leaves of marsh grasses with the help of tenacious fingers and toes. At
front paws the palm forms a kind of sucker.
The adult midgefrog grows not for long, but very actively. Its length after
metamorphosis does not exceed 14 mm, but right till one month it reaches the
size characteristic for adult individual. In the same time it becomes sexually
mature and starts spawning. So high growth rate is explaining by one feature
of its physiology: is an annual frog. Closer to an autumn adult midgefrogs
quickly grow old. Besides when small two-winged insects vanish, these frogs
lose an only source of forage and are quickly exhausted.
Motley midgefrog lives in wet places – under leaves of perennial grassy plants.
This species is widely settled in swamps of Siberia and eats mosquitoes. This
tiny frog has spotty colouring – in it orange and brownish-green colors, located
by chaotic spots are combined. The size and amount of spots may strongly vary
at different individuals.
Courtship games of motley midgefrog begin in the middle of summer. Males call
females, perching on branches of bushes and high stalks of grasses. Voice of
this frog is shrill squeak. Short sound signals follow one by one in some seconds
during 2 – 3 minutes in succession, if the male is not disturbed by anybody.
At the meeting of two males sound signals follow one by one, almost not interrupting.
Eventually, weaker male stops “duel” by the first and leaves out.
Female in common with male moves to water and spawns near the coast up to hundred
very small eggs. In them also there is a poisonous substance, and it is enough
quantity of it to protect eggs from encroachments of small aquatic predators.
But tadpoles of this species are lack of such protection, and can hope only
for their own speed of movement and reaction. They gather to big shoals and
keep in well warmed up places of reservoir.
Close species of midgefrogs live in Siberia:
Little Red Riding Hood midgefrog (Miniranula crystallodermata) is one of tiniest
species of the genus: the length of adult female is about 19 mm, male – up
to 14 mm. At this frog skin is poor pigmented and so thin, that through it
interiors are visible. Only on head of this frog there is a big red spot, hence
it has received its nickname. It lives in shady places and eats exclusively
midges and fungus gnats. Adult frogs frequently can be found on old mushrooms
bored by insects. Voice of this species is lingering silent trill.
Leopard midgefrog (Miniranula leopardina) is one of most colourfully looking
midgefrogs. Its length is about 25 mm. Background color of skin is ochre-yellow,
on it small black an irregular-shaped spots are scattered. Limbs of this frog
are rather short, and it seems more robust, than its relatives. It swarms up
plants good, and meets on stalks and leaves at height of more than one meter
above the ground. This frog can eat not only mosquitoes, but also larger insects
– small moths.
Lemon midgefrog (Miniranula citrina) is unusually looking species of frogs.
Skin of this frog is monotonous canary-yellow, and on throat there is bright
yellow area. Eyes are rather large: this species leads nocturnal habit of life,
and hides in foliage and holes of small animals in day time. At night these
frogs become more active, jump on stalks of grasses and bush leaves. Voice
of lemon midgefrog is abrupt “yelping” sounds.
Moonlight midgefrog (Miniranula selena) differs from other species by “varnish”
blue colouring. Like previous species it is a nocturnal animal and has large
eyes. It is tiny species of midgefrogs reaching the length of 18 – 19 mm. It
lives mainly in thickets of marsh plants at riverbanks and lake coasts. The
voice of this frog resembles cricket chirring.
Mantid-mimic frog (Mimohyla mantidomima)
Order: Tailless amphibians (Anura)
Family: Tree Frogs (Hylidae)
Habitat: swamp regions of China.
Reservoirs in tropics (however, in any latitudes) are the true battlefield.
Predators from infusorians up to insects, fishes and amphibians are plentifully
represented here. Even plants in reservoirs may be predators often. Therefore
ones unable to be a predator, or unable to resist stronger predator, develop
fantastical and refined strategies of survival. Some animals hope for passive
protection, growing armours and needles interfering attack of predator. Others
prefer to seek safety in flight or to hide, and third ones hope for strong
poison. But the most skillful tactics is to show a predator, that things seen
by it are actually not what it expects. Imitators are among various animals
and in the various habitats. But the indispensable condition of their occurrence
is a presence in the same habitat of the creature which is able to protect
itself and warns predators about it. The interesting insect lives in bogs of
China – it is aquatic soothsayer. This creature is successfully protected from
water bugs and predatory medium-sized fishes. Noticing a predator, aquatic
soothsayer demonstrates strong trapping legs, showing readiness to self-defence.
Having received a serious chipped wound, the predator recedes. At such protected
creature completely unexpected simulator had appeared – it is one local tree
frog named mantid-mimic frog. Due to dexterous imitation of aquatic soothsayer
this amphibian can feel like protected from smaller water predators. It is
very important for the frog, because its length is only about 7 – 8 cm.
The frog imitates not whole soothsayer – it too differs from this insect in
body shape. But to frighten underwater predator it is enough to imitate the
forward part of body of aquatic soothsayer shipped in water. At mantid-mimic
frog there is thin body simulating a prothorax of insect. It is colored yellowish
with thin faltering longitudinal strips. Hips and shins expanded as blades
simulate the terrible weapon of insect – the forward pair of legs armed with
spikes. Like trapping legs of soothsayer they are colored green from above,
and grey from below. The basis of hips has two light spots (it is the imitation
of insect eyes), and on back there is the turned triangle darker rather than
other colouring. It takes off the head of insect. On expanded lobe-like hips
and shins along the edge there is a pattern like slanting short strokes imitating
thorns on trapping legs of soothsayer.
Forward paws of mantid-mimic frog are very thin and have tenacious fingers.
When the amphibian floats at the surface of water, having grasped any floating
plant, and its bottom part freely hangs down in water, the complete illusion
of aquatic soothsayer trapping catch is created. The small fishes having the
experience of this insect attack, try to keep aside the floating frog. To simulate
the aquatic soothsayer even more precisely, mantid-mimic frog moves back paws,
imitating movements of insect clearing. Toes with swimming membranes at this
moment are compressed and do not break accuracy of imitation.
The mantid-mimic frog leaves water seldom, and prefers to live on the cover
of floating plants. It eats small insects hovering above floating plants in
searches of flowers, and catches them by long tongue.
This amphibian breeds similarly to the majority of frog species. The mantid-mimic
frog does not have complex forms of building behaviour, as at some other species
of amphibians. Pair of animals spawns eggs (up to 500 grains of roe in one
laying) in thickets of cane or other coastal vegetation: here eggs are better
protected from casual predators. Approximately after 5 – 8 days from eggs tadpoles
hatch. They are a little bit similar to parents: their body is also narrow
and slender. Tadpoles of mantid-mimic frog live among coastal vegetation, and
eat smallest animals, scraping them from stalks of plants. They sit among stalks
vertically, and do not like to swim to long distances. At danger tadpoles prefer
to hide among plants, and freeze, nestling against stalks. For the best masking
their colouring represents longitudinal dark green lines on brown background.
At the second month of life the length of tadpole surpasses the length of adult
frog, and to the beginning of metamorphosis the tadpole of mantid-mimic frog
is almost twice longer, rather than adult individual. About two thirds of its
length muscled tail amounts. Till the metamorphosis tail is resorbing and simultaneously
the body of tadpole gets the shape characteristic for adult amphibian of this
species. On hinder legs characteristic lobe-like outgrowths appear, and head
becomes wide and flat. Passed through metamorphosis young mantid-mimic frog
is only a quarter shorter than adult individual. This is the original adaptation
to imitation of aquatic soothsayer - the amphibian “slips” through the age
when soothsayers are too small, and there is no sense to imitate them.
Life expectancy of mantid-mimic frog is about four years.
Branchial
tadpole (Branchiosuga nosferatu)
Order: Tailless amphibians (Anura)
Family: Neotenic frogs (Pseudocaudidae)
Habitat: tropical ponds and rivers of South America.
In fauna the phenomenon of neoteny is very much distributed: larval stage of
individual development gets ability to breed, not starting to metamorphosis.
Among vertebrate animals such phenomenon is shown by some tailed amphibians
like mole salamanders (Ambystoma). Larvae of these amphibians are known as
“axolotl”. Some other tailed amphibians, for example, Proteus and Siren, represent,
in the main, becoming adult larva which had lost the adult stage. In human
epoch among tailless amphibians such phenomenon was not known.
But in Neocene one of numerous species of South-American frogs had made that
earlier was possible only to its tailed relatives: it had lost adult “frog”
condition under rather unexpected circumstances. Tadpoles of this species able
to normal breeding, live in rather unusual place: at gills of huge fishes boltergillers
(Potamocetus balaenognathus), eating river plankton, and occasionally on
gills of other big fishes. They are species of amphibians had mastered parasitic
habit of life - being mature they eat exclusively blood of fishes.
These creatures completely passed to breeding at larval stage and had lost
an adult stage of the frog. The parasitic way of life influenced upon anatomy
of this animal. Body of branchial tadpole is flat and oblong; mouth has transformed
to sucker. In mouth there are two corneous plates, with which tadpole bites
through epithelium of gills of the host fish. The body of animal is about 5
- 6 cm long; it is covered with thin translucent skin of grayish color through
which interiors and blood vessels appear through. Because the tadpole spends
all adult life on fish, it does not have necessity to swim to anywhere. Therefore
its tail is very short, accounting about quarter of general length of animal.
In spite of the fact that this creature is only the adult tadpole, at it hinder
legs serving for keeping on gills of fish develop. At these paws only two toes
develop, forming some kind of “pincers” clasping branchial arch of fish.
Sense organs at branchial tadpoles are advanced very poorly: eyes are appreciably
reduced, and there were only few tens of sensitive cells of former lateral
line. Organs of smell sense are well advanced only at young individuals, but
not at adult males.
At these tadpoles males are smaller than females, and are more active than
them: male can move in branchial cavity of fish, finding for females ready
to breeding. The female is larger; her body is convex, and oral sucker is stronger.
Once per some days pair makes a plenty of small eggs (up to 100 ones that is
a big number for small animals). Eggs develop in thickness of water: they swell
in water, and after two - three days from them very small larvae hatch.
The early-aged tadpole of this species lives in plankton and eats it, filtering
through gills. It is tiny and practically completely transparent. Later, having
reached length about 2 cm (tail accounts more than half of length), the tadpole
settles on gills of the host fish. It is easy for making: the fish, properly,
finds it itself together with other plankton. First time the young branchial
tadpole does not harm the host fish: it only scrapes plankton accumulated on
its gills. Adult animal passes to parasitism – it starts to bite through gill
epithelium and to suck blood.
To lower an intraspecific competition in the limited vital space, at these
parasitic creatures the original mechanism of regulation of population amount
had developed. Adult individuals eat not only blood of fish. They also may
be cannibals, killing significant part of young tadpoles settling on gills
of fish. Thus the overpopulation of the host animal by parasites is prevented.
Young tadpoles have real chance of survival only if at the infected fish there
is a small population of adult tadpoles.
Toby
frog (Vesicorana toxidermata)
Order: Tailless amphibians (Anura)
Family Spherical frogs (Sphaeroranidae)
Habitat: the wood rivers of South America.
After ice age, marked with itself the border of Holocene and Neocene, climate
became more humid, and woods had occupied again extensive territories in equatorial
zone of Earth. In territory of South America the impassable selva again
was spread. Current of rivers of Amazon region have a little changed after
droughts of glacial epoch, but in Neocene the basin of Amazon and Hyppolite
flowing in parallel to it has occupied approximately the same area, as an Amazon
region in Holocene epoch.
The damp, periodically flooded rainforest, or igapo, is a fine place for life
of various frogs and toads. Here it is possible to find various shelters and
reservoirs for development of tadpoles, therefore the frog population of this
place is especially numerous and various. At night woods of Amazon region are
resounded by voices of various frogs. Among them the voice of one of local
frogs, sharp abrupt whistle, is remarkable. The owner of so remarkable voice
is frog about 10 cm long keeping among wide-leafed marsh grasses. By body shape
it differs from the majority of frogs unless by larger and wide head, and small
eyes are shifted to sides a little. It is colored rather brightly: back is
black with small red spots on shoulders, hips and waist; belly has red spots
on white background. This amphibian does not hide in presence of large animals,
and it looks, they diligently avoid meetings with it. The name of this species
is toby frog.
Two features unite this frog with its “double” among fishes. First, the skin
of this frog contains strong poison. And second, the toby frog has developed
an interesting way of the warning about its virulence. Skin on its belly is
very elastic. In case of danger this frog quickly inflates as a sphere, swallowing
air or water. Thus it rises on paws so, that bright colouring of stomach becomes
especially distinct. Similarly the toby fish (Tetraodon) turns to sphere, being
disturbed. At puffed frog on skin drops of poison involuntarily appear squeezed
from skin glands on sides. Poison at it has unpleasant sharp smell, warning
possible aggressors about danger.
However, in nature absolute protection does not happen. Some birds have adapted
to eat toby frogs, avoiding their poisonous protection. They kill and tear
apart frog by claws, and then simply peck meat, not touching poisonous skin.
Here toby frog loses to fish “double” in armament: at fish there are even poisonous
meat and interiors.
When threat of life will pass, frog simply weakens stomach sphincter and by
contraction of abdominal muscles lets air or water outside through a mouth.
This species has staked on its own virulence, and during all life protect itself
by chemical weapon – eggs and tadpoles at toby frog are also poisonous.
Eggs of this frog are colored red because of abundance of carotene – they develop
in reservoirs with slow current, poor in oxygen, and carotene has in addition
property to fix oxygen. At the same time red colouring warns water animals
that eggs are poisonous. In clutch at this species there may be up to 200 grains
of roe. Parents simply leave eggs to the mercy of fate: the survival rate of
posterity at this species is rather great even without additional care. Tadpoles
of the toby frog have bright colouring too: they are red with black speckles
on sides. They have feather-like external gills necessary for life in water
poor in oxygen. Besides at tadpoles lungs develop early. They eat filamentous
algae and keep in shallow waters, where they have no competitors. These tadpoles
are not afraid of coming nearer animals – they, as well as adult frogs, are
poisonous. The stage of tadpole lasts about 2 months. Having reached length
about 4 cm, the tadpole turns to young frog and goes to land. At the age of
7 – 8 months young frog can take part in spawning.
Stream suckermouth (Ancistrogyrinus lampetrifrons)
Order: Tailless amphibians (Anura)
Family: New Zealand false salamanders (Virilogyrinidae)
Habitat: mountain rivers of New Zealand.
In historical epoch the fauna of New Zealand had suffered the large damage
from the human activity connected to “enrichment” of it by various species
of animals, unusual for natural ecosystems of islands. Among invaders there
were various species of invertebrates and vertebrates, and also plants. In
woods of islands various mammals, and in rivers fishes from various continents
had appeared. There were large Australian tree frogs of genus Litoria among
animals introduced to New Zealand.
Climatic changes at the boundary of Holocene and Neocene had determined the
unusual direction of evolution of these creatures. At the cooling of climate
these amphibians suffered the tightening of metamorphosis. This phenomenon
had been well-known at newts of various species and other tailed amphibians
dwelt in Northern hemisphere. In New Zealand some populations of descendants
of introduced tree frogs had gradually turned to sexual matured tadpoles and
had lost the ability to turn to adult frogs. Actually they had became tailed
tailless amphibians, once again emphasizing the reserve of names given by people.
In mountain areas of New Zealand, in clean quickly flowing rivers there are
many various species of such “overgrown tadpoles” occupying various ecological
niches in reservoirs. One of usual species is the stream suckermouth, an amphibian
about 40 cm long. Its body is lengthened; strong muscled tail makes approximately
2/3 of general length.
Head of this creature is poorly separated from the body; it also is wide and
flat. Small eyes are placed at edges of head and are directed forward and sideways.
Scraping mouth looking like sucker is placed at the bottom part of head. The
specific name of the animal means “having the head of lamprey” because of the
similarity in structure of mouth, and the mouth shape also had determined its
everyday name. On top and bottom jaws of this amphibian strips of corneous
denticles, bordering mouth in front and behind, are advanced. With their help
stream suckermouth scrapes larvae of midges and other sedentary and inactive
invertebrates from stones. In connection with such way of feeding branchial
apertures are turned upwards. Lungs at this species are rather small – this
animal receives oxygen using branchial and skin respiration.
Paws of stream suckermouth are short; hinder legs are only a little bit longer
than front ones. The animal can rake by paws stones in searches of forage,
and at danger it can quickly dig in ground. When stream suckermouth swims,
paws are densely pressed to sides, and the tail is the main organ of movement.
Usual colouring of this animal is soft: the top part of body and sides is grey
with small black spots on back and head. On sides there is less amount of spots,
and the stomach is absolutely lack of them. The bottom half of body at females
and males out of spawning season is colored similarly – it is milky-white.
In spawning season stream suckermouthes change: the throat and chest of males
turn orange-red, head blackens, and on sides black faltering vertical strips
appear. Besides on tip of tail of males in spawning season the long string
grows (similar to “ornaments” of some armored catfishes of family Loricariidae
of Holocene epoch), and the general length of the male at this time may exceed
half-meter. Upon termination of spawning season this string is resorbed.
The spawning season begins in spring (in Southern hemisphere it is the end
of August – first half of September), when mountain snows thaw, and also rivers
become deeper. Males occupy individual sites and protect them from congeners.
At borders of sites there are skirmishes at which males show to each other
bright stomach and try to drive the contender off by impacts of head to sides.
When the female swims to the site of male, it begins courtship rituals and
tries to keep the female, sticking by mouth to her side and keeping by paws
for stones and driftwood. The center of the site of the male is the flat stone
which surface is carefully cleared of algae and sedentary animals.
The inhabiting in quickly flowing streams causes the occurrence of the special
reproductive behaviour at these amphibians. The male does not produce liquid
sperm, and lays the spermatophore on the cleared stone. The female swims above
the stone and takes it by mobile edges of cloaca. Thus, at stream suckermouthes
the internal fertilisation takes place. It raises the probability of fertilisation
– in quickly flowing water the liquid sperm may be simply washed off by current.
The female lays on the bottom side of stones a small amount of large eggs (about
60 – 70 ones about 1 cm in diameter) with sticky environment. Approximately
in one month the tadpoles distinguished from adult animals by absence of legs
and dark colouring hatch from them. They reach sexual maturity at the age of
2 years. Life expectancy of this species may be about 15 – 18 years.
The idea about the existence of this group of animals is stated by Tim Morris, Adelaide, Australia.
New Zealand cave neosalamander (Cavernogyrinus caecus)
Order: Tailless amphibians (Anura)
Family: New Zealand false salamanders (Virilogyrinidae)
Habitat: underground reservoirs of New Zealand.
In Neocene at New Zealand the separate group of amphibians, New Zealand false
salamanders, prospers. They are descendants of Australian tree frogs of genus
Litoria introduced to islands, though all representatives of this group resemble
externally any caudate amphibians of North Hemisphere. They had appeared
as the result of climatic changes at the boundary of Holocene and Neocene.
The
cold climate had caused the delaying of metamorphosis and occurrence of group
of neotenic amphibians keeping in adult stage the set of larval features.
In early Neocene their active adaptive radiation began, and as the result
of it,
at the islands many species of these animals had appeared. They are adapted
to various conditions of life, and one species, New Zealand cave neosalamander,
had settled underground reservoirs.
Cave reservoirs represent the habitat distinguished by poverty of food resources.
Therefore the majority of cave inhabitants is small creatures. Besides the
basic sources of food for cave inhabitants are other animals, lower fungi
and bacteria, and also carrion. It considerably reduces opportunities of
settling
of caves by live organisms.
The predator having low rate of metabolism is the creature prospering in
such ecosystems. New Zealand cave neosalamander belongs just to such species.
This
is small animal about 20 cm long, with delicate translucent skin of “ivory”
yellowish-white color. At this amphibian there is thin long body; tail makes
about half of its general length. It is bordered with wide fin plica stretched
on back almost up to the level of forepaws. Head at this species of amphibians
is flat, rounded, with wide mouth. This amphibian breathes mainly by gills
– lungs are very poorly developed.
Paws of New Zealand cave neosalamander are short and have three small toes.
This amphibian gets out on land seldom, preferring to swim in cold water
of underground rivers rich in oxygen. Eyes of this amphibian are completely
reduced
– on head of the animal only two dark spots instead of eyes are appreciable.
At New Zealand neosalamander even rudiments of optic nerve did not remain,
but there is a curious sense of “skin sight” – the animal reacts to light
falling on skin and tries to hide from it in dark places. Such phenomenon
was known
at caudate amphibians of Holocene epoch. Two short conic wattles in corners
of mouth help this blind animal in search of small invertebrates dug in ground.
Along each side of New Zealand cave neosalamander the line of lateral line
cells passes. Very sensitive organs of lateral line help the animal to define
presence of moving objects in absolute darkness. Also for this amphibian
keen sense of smell is characteristic. Nostrils are surrounded with two leaf-looking
outgrowths which permit to define the direction to source of a smell.
Due to so advanced sense organs New Zealand cave neosalamander occupies high
place in food pyramid of cave reservoirs. It eats crustaceans living nearby,
and gathers insects fallen in water. The consuming of insects – plentiful
and nutritious food – permits this species to reach rather large number:
in large
cave lakes populations total some thousand individuals of these amphibians.
When in underground waters the dead animal from ground surface gets, New
Zealand cave neosalamander can eat carrion, finding it by smell and tearing
off small
pieces of food by mouth.
Seasonal prevalence in spawning at this amphibian is not present. Females
are ready to breeding depending on physical condition up to 2 – 3 times once
a
year. The female ready to spawning emits the odorous substance strongly involving
males. Near one female up to ten males of various ages and sizes may gather.
Gradually stronger males drive off weaker ones, and soon only one male starts
to escort the female. Occasionally the applicant male keeps nearby to them,
trying to wedge in courtship display.
These amphibians breed, spawning up to 250 small eggs in cracks between stones.
During the egg spawning male is twisted around of female’s body and kept
on her, holding her paw. Pair may keep “embraces” till some minutes, and
then
simultaneous spawning of sexual products in water follows.
Eggs develop for rather long time – about three weeks. For this time the
part of them may be lost from predators, but eggs fallen in remote places,
develop
successfully. Small larvae of New Zealand cave neosalamander feed with bacterial
film and fungi, scraping the food from stones. They keep solitarily and grow
slowly: legs develop at them at the age of about eight months. Larvae are
very cautious: their main enemies are crustaceans and adult congeners. Young
New
Zealand cave neosalamanders reach the sexual maturity only to 3-years age,
but can easily live up to 30 – 35 years.
The idea about the existence of this group of animals is stated by Tim Morris, Adelaide, Australia.
Neohanasaki (Neohanasaki aotearoae)
Order: Tailless amphibians (Anura)
Family: New Zealand false salamanders (Virilogyrinidae)
Habitat: New Zealand, slowly flowing rivers and big lakes of Southern Island.
New Zealand false salamanders are the separate group of amphibians generated
in conditions of island isolation. From early Neocene their active adaptive
radiation began, and its result is the presence in New Zealand of several
variations of these animals, which occupy various ecological niches, avoiding
the competition
with each other. The majority of New Zealand false salamanders is presented
by small animals, but one species represents large amphibian up to one and
half meters long. This species is named neohanasaki. “Hanasaki” is the Japanese
name of giant salamander, the large amphibian inhabited Japan Islands in
Holocene epoch. Neohanasaki is the largest species of “adult tadpoles” of
New Zealand.
New Zealand neohanasaki is similar to the prototype from Eastern Asia. At
this amphibian there is wide, flat and angular head, on which edges small
eyes are
located. In corners of the mouth two short wattles with wide bases grow.
At neohanasaki, as at all representatives of New Zealand false salamanders,
larval
features are kept: wide branchial apertures supplied with skinny valve, and
skinny fin bordering long tail. The tail makes more than half of general
length of this animal.
Skin of neohanasaki is knobby, and on each side of the body small plicas
stretch. When this amphibian moves, its skin waves, and it seems, as if the
skin was
intended for larger animal. But there is a deep biological sense in it –
skin helps neohanasaki to breathe, especially in cold season. Neohanasaki
moves
in water, bending the body wavy and pushing from bottom by short paws. Colouring
of neohanasaki is dark brown; throat and stomach are colored beige with small
brown spots. When this animal lies motionlessly at the bottom among underwater
plants, it may be mistaken for the piece of rotten tree trunk.
By its nature neohanasaki is inactive animal representing the ambuscader
like European catfish. Usually it hides under driftwood or motionlessly lies
among
vegetation, expecting while the prey will approach to it itself to the distance
of resultative throw. This species does not pay attention to small fishes
and tadpoles, even when they twitch its skin. It hunts for large water animald
– crustaceans (river crayfishes and crabs), large fishes, and also medium-sized
tetrapods appeared in water. Its prey often may include related species of
“adult tadpoles”.
In spawning season this animal turns very active and mobile. Male gets bright
courtship dress: its stomach turns yellow with small black spots, and on
tail fin the line of jags grows. Trying to impress the female, male turns
to her
by side and displays the splendid serrated crest on back. If the female is
interested in the male, he continues demonstration. During the second part
of courtship the male shows bright stomach to the female. It emerges to the
surface of water, swims above the site, and splashes by tail, declaring about
rights to this territory. From time to time the male pours the female with
waves of water, displaying the force to her. This species spawns eggs in
big bush of water plants: male and female creep in it together and simultaneously
spawn sexual products.
The clutch of neohanasaki may number up to 500 – 600 eggs surrounded with
mucous mass. The male displays the care of posterity: it protects territory
up to
larvae hatching, driving away or simply eating any animals representing danger
to eggs. From time to time it slaps by tail on the water surface – it is
not only the signal to applicants to keep farther, but also the way of enrichment
of water with oxygen. When from eggs tadpoles hatch, male does not abandon
them. First days of life tadpoles keep near its head, and male carefully
protects
them. The top layer of male’s skin at this time starts to swell and to exfoliate.
Tadpoles eat it in the first days of life, and due to this feature their
survival rate in critical period is very high. The grown up posterity leaves
male and
swim to the independent life full of dangers. The main danger for young neohanasaki
is its congeners: at this species cannibalism is advanced. Therefore till
first years of life the posterity keeps in shallow streams, where eats larvae
of
insects. Sexual maturity at neohanasaki comes at the age of about seven years
at length up to 60 cm. Life expectancy reaches 90 years and more.
The idea about the existence of this group of animals is stated by Tim Morris, Adelaide, Australia.
Swamp terragyrinus (Terragyrinus paludiphilus)
Order: Tailless amphibians (Anura)
Family: New Zealand false salamanders (Virilogyrinidae)
Habitat: New Zealand, cold Alpine swamps and marshy meadows.
Among Neocene inhabitants of New Zealand the family of “adult tadpoles”, the
separate group of amphibians had lost the adult stage has the special rank.
Various species of these amphibians had occupied on islands the ecological
niches similar to those at tailed amphibians of northern hemisphere. One species
of these amphibians is swamp terragyrinus. The majority of its relatives remained
aquatic animals, but this species spends on land much more time, than they
do. It is the inhabitant of swamps of Alpine zone overgrown with plants.
Swamp terragyrinus is very similar to large salamander. This is long-bodied
animal at which the tail makes about 2/3 of general length. The length of this
amphibian is about 20 cm.
At terragyrinus paws are well advanced, and this amphibious can freely move
overland. It lives in damp places - in swamps and lakes near to edge of mountain
glaciers where water and air are very cold. This amphibian lives among grass,
and due to thin flexible body freely creeps among stalks, escaping from enemies.
Head at terragyrinus is narrow and has pointed muzzle. Branchial apertures
are small; for protection of gills from drying they are closed by special valves
of skin. Eyes at this amphibian are small.
Body of animal has grey color with dark “marble” pattern; stomach is white.
In courtship season at males throat gets bright red color. Skin has very important
role in gas exchange – terragyrinus has small sac-like lungs which can hardly
provide even a half of requirement of animal in oxygen. When this amphibian
dives, instead of lungs gills start to work. But the skin also provides animal
with oxygen. Terragyrinus does not endure rise of temperature of water, because
thus the contents of oxygen in it falls. In hottest days of summer these animals
leave land and hide in cold bottom layers of water of mountain lakes. But terragyrinus
keeps activity even at minus temperatures (up to - 2 °Ñ).
Terragyrinuses eat insects and small snails crushing their shells with the
help of special corneous plates on jaws.
The courtship season at these amphibians begins in spring when the rough thawing
of snow and ice takes place in mountains. After short court ritual the female
lays on coastal vegetation large slimy mucous clod of eggs (about 500 ones
in clutch), covered with the common environment. All this time the male drives
competitors away from the female. It behaves very aggressively, and attacks
even fishes. When eggs swell, male penetrates into the clutch and ejaculates
sperm liquid. After fertilization of eggs both parents leave clutch.
The incubation lasts till about three weeks. Young ones are similar to tadpoles
of frogs and differ in translucent covers of body. Larvae of terragyrinus live
among vegetation and eat microscopic algae and microscopic animals. At the
age of two years they reach the size of adult animal and begin able to breed.
Terragyrinuses have the slow metabolism and grow slowly. But they differ in
significant longevity – on the average, life expectancy of these animals makes
55 – 58 years.
The idea about existence of this group of animals is proposed by Tim Morris, Adelaide, Australia.