Calotes is commonly called garden lizard. It is included in:

Phylum – Chordata,

Sub-phylum – Vertebrata,

Class – Reptilia

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Genus – Calotes

Species ā€“ Versicolour

Morphology:

Calotes has an elongated lizard like body. It is about 35-40 cm long including a tail. It has olive green or grayish above and whitish below. Male brightly coloured- golden yellow with greenish tinge. Throat is scarlet red often with a black transverse bar.

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Young females often show two light yellow dorsolateral stripes. The calotes changes colour due to contraction and expansion of pigments in chromatophores (pigment cells) which is controlled by melanocyte stimulating hormone (MSH) of anterior pituitary gland. The male is larger and stronger than female. The body is divided into 4 parts- head, neck, trunk and tail.

The head is more or less triangular in shape. The snout is short and bears a pair of nostrils. The eyes are provided with movable nictitating membrane in addition to upper and lower eyelids. The mouth is a transverse aperture. It is terminal in position and lips are absent. The tympanum is situated behind eyes. A small narrow neck joins the head with trunk.

The trunk is situated behind the eyes. The trunk is elongated and bears two pairs of appendages, the fore limbs and hind limbs. Each forelimb is divisible into branchium (upper arm), antebrachium (forearm) and manus (hand). The hand further comprises a shortcarpus (wrist) and the metacarpus (palm) and 5 digits (fingers) and the digits are provided with sharply pointed claws.

Like wise the hind limb is divisible into femur (thigh), middle crus (shank) and pes (foot). The foot further comprises a tarsus (ankle), metatarsus (instep) and 5 digits (toes) of varying sizes, each ending in a curved, pointed claw. The cloacal aperture or vent is a transverse opening and is situated in the posterior-ventral part of the trunk and at the base of the tail . in adult male the base of the tail, just behind the the cloacal aperture, becomes swollen due to hemipenis. The entire body is covered by epidermal scales.