Department of Zoology at ANDC/Zoology Museum/Museum specimens/Reptilia

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Class Reptilia

Date & Time : 19, October 2017 08:30



General Characteristics of Reptilia

  • cold- blooded animals.
  • skin is covered with horny scales or scutes.
  • no glands are present on skin.
  • limbs are reduced and pentaductyle type.
  • skull consist of single median occipital condyle.
  • mandible present in pieces.
  • ribs form the true sternum.
  • lungs for respiration.
  • heart is three chambered.
  • R.B.C. are nucleated.
  • both the kidneys are provided with separate ureter.
  • typical cloaca present.

Classification of Reptilia

A Few Examples

1.Chelone

Common name-Green Turtle.

Distribution-

Habitat-Marine.

Food-marine algae.

Green Turtle resting

Identifying characters-

  • Body color-olive or brown with yellowish spots.
  • Body length-85-110 cm.
  • Integument- covered by smooth shell.
  • four pairs of coastal shields on dorsal surface fitting closely.
  • Head-one pair of prefrontal shields covers the head.
  • EyesConsisting of eyelids and nictating membrane.
  • Limbs-wing-like paddles with only one claw.
  • Tail is short.
  • Unhooked jaws are present.

2.Testudo

Common name-Land Tortoise.

Distribution-

Habitat-

Food-Worms and Insects.

Testudo graeca 12

Identifying characters-

  • Body length-30 cm.
  • Carapace-very convex, no nuchal plate.
  • Plastron-concave, central and marginal scales are yellow starred.
  • Feet-phalanges are reduced to two in digits.
  • Male is smaller than female.
  • They can live without water for along time.
  • In cold water, it hibernates underground.

3.Hemidactylus

Common Name-House lizard.

Distribution

Food-insects.

Hemidactylus

Identifying characters

  • Body length-25 cm.
  • Body color-pale green.
  • Integument-scaly,minute and smooth scales.
  • Eyes-small eyes but eyelids are fused.
  • Ears-like openings whichare vertical.
  • Tongue-short, stcky and slightly notched.
  • Tail-long tail having a great power of regeneration.
  • Digits-smooth surface,clawed and two rows of ridged lamellae which help in movement.
  • several femoral pores are present on the thigh of male.

General characters-

  • amphicelous vertebrae.
  • parietal organs present.
  • oviparous.
  • one supra-temporal arch is present.

4.Varanus

Common Indian Monitor.jpg

common name-common Indian monitor.

Distribution-

Habitat-burrows and trees.

Food-reptiles, mammals and dead bodies etc.

Identifying characters-

  • body length-60 cm.
  • Body color-brownish color with darker spots in rows.
  • Integument-skin is covered with scales -dorsal and vetral.
  • Dorsal-very small scales with tubercles and ventral scales are arranged in rows.

5.Ophiosaurus

Common name-glass-snake or limbless lizard.

Distribution-

Habitat-burrows and bushy localities.

Food-snails, mice, insects,worms and small lizaards.

Identifying characters-

  • Body-long, cylindrical and similar to snake.
  • Head-similar to the typical lizard.
  • Eyes-movable eyelids on eyes.
  • Ear-openings represents the ear.
  • Tongue-consist of anterior(thin,extensile and retractile) and posterior(thicker).
  • Integument-covered by scales which is further underlyning by bony pltes.
  • Limbs-reduced to small cloacal spikes(a pair).
  • Tail-long and very brittle.

6.Draco

Flyinglizard.jpg

Common name-flying lizard, or flying -dragon.

Distribution-found in Sumatra,Java, and Borneo. found in Madras in India.

Habitat

Food- 

Identifying characters-

  • Body-dorso-ventrally compressed.
  • Body length-25 cm.
  • Eyes-very small eyes, but eyelids are complete.
  • There are three hooks which are pointed,one isshort on either side and the other one is long in the middle.
  • Limbs- forelimbs and hindlimbs are extended as a pair of large wing like membranes,called pategia. pategia is supported by ribs.
  • Tail- it is very long and slender in shape.
  • gular pouch is present in both the sexes (orange in males and blue in females).
  • only male has a small nuchal crest.

7.Viper

Common name-daboia.

Distribution-

Habitat-rocky bushy regions.

Videos of Viper

Identifying characters-

  • Body-elongated.
  • Body color-pale brown but underparts are yellowish white. There are three longitudinal series of black spots.
  • Body length-one and a half of metre.
  • Head-triangular head with imbricate scales on upper surface.
  • Eyes-beuatiful eyes with golden iris and elliptical pupil.
  • Snout-angulate, nasal opening is quite prominent.
  • Scales-scales are arranged in thirty rows.
  • Supra-labials-10-12,4th is the largst.
  • General characters-
  • viviparous.
  • carnivorous.
  • it's venom is haemotoxic.

8.Elaps

Common name-coral snake

Distribution- found in  South America and the Lesser Antilles.

Habitat-

Food-

Identifying characters-

  • Body- elongated and cylindrical.
  • Body color- pretty black and red rings alternate with one another.
  • Body length- about 1-1.5 metre.
  • Integument- smooth scales are present which forms about 15 rows.
  • Head- small, not distinct from tail.
  • Eyes- smallwith vertical pupil.
  • No teeth in maxillaries behind the poison fangs.
  • Tail- short but round

9. Dendrophis

Common Name- Tree snake.

Distribution- found in South East Asia and Australia.

Habit and Habitat- abortal in habit.

IDENTIFYING CHARACTERS-

  • Body- elongated and cylindrical in shape.
  • Body length- about two metre long.
  • Integument- scales are present which are keeled and form 13-15 rows.vertebral rows are enlarged.
  • vntral rows consists of lateral keels( a pair), and notch ( help in climbing) on each side.
  • Eyes- covered by transparent membrane which is fused.
  • Ear- tympanic membrane is absent.
  • limbs- absent , girdles are also absent.
  • No gangs (harmless).

10. Crocodilus

Common name- marsh crocodile or muggar of India.

Distribution- found in India, Burma, Malacca, Beluchistan.

'Habit and Habitat'- like to live in rivers, ponds, tanks and marshes.

IDENTIFYING CHARACTERS-

  • Body- exoskeleton is present, horny thiock epidermal scales consist of dermal bony plates.
  • Body color- upper parts are dark olive brown.
  • Body length- about 4-5 metres.
  • Head- triangular and  rough at the top.
  • Snout-  stout rather broad.
  • upper and lower jaws are present. teeth are 38 in number.

             Largest tooth- 5th of upper jaw.

  • Limbs-  pentadactyle, five fingers with four toes.

              fingers are webbed at base and outer toes are broadly webbed.

  • Ear- covered by movable flaps of skin.
  • Nuchasl scutes- 6 in number, packed closely together forming a square.
  • Oviparous and predators.