Calotes ceylonensis, Length of head one and a half times its breadth; snout a little longer than the orbit; forehead concave; cheeks swollen in the adult male; upper head scales unequal, smooth; canthus rostralis and supraciliary edge sharp; two well separated spines above the tympanum, the upper and anterior one mid way between it and the nuchal crest; diameter of the tympanum half that of the orbit; 10 to 12 upper and as many lower labials. Body compressed; dorsal scales rather small, smooth or faintly keeled, the anterior and upper ones pointing backwards and upwards, the others straight backwards, larger than the ventrals, which are strongly keeled and mucronate; 54 to 60 scales round the body. No trace of a gular sac; gular scales strongly keeled, as large as the ventrals; an oblique fold in front of the shoulder runs across throat covered with small granular scales. Nuchal crest formed of 10 or 12 small spines; no dorsal crest. Limbs moderate; third and fourth scales are sub equal; fourth toe distinctly longer than third; the hind limb reaches to the tympanum or beyond. Tail long and slender; in the adult male it is markedly swollen at the base, with large, thick, keeled scales, those of the upper median row forming a slight serrated ridge (Deraniyagala, 1953; Smith, 1935 Taylor, 1953).

The body color is changeable from grayish brown to light blue or dark brown, back of the head and anterior part of back pale brownish, divided in to more or less distinct spots by dark transverse bars; hinder part of back and tail with dark cross bars; upper lip with a pale strongly defined stripe, which extends to beyond the ear; sides of neck and chest black or white with black reticulations; gular region grayish or blackish; belly pale brown with more or less distinct angular bands (Deraniyagala, 1953; Smith, 1935 Taylor, 1953)

Calotes ceylonensis is recorded only from the semi evergreen monsoon forests, plantations and home gardens of the dry and intermediate zones up to 400 m within the well shading riverine-forested areas and poorly in the home gardens (Das & De Silva, 2005; Erdelen, 1984; Karunarathna & Amarasinghe, 2008; Manamendra-Arachchi & Liyanage, 1994). This species is endemic to Sri Lanka.

This species is largely arboreal and active during the day, widely spared within the well shading riverine-forested areas and poorly in the home gardens. They specially feed on butterflies; honeybees and other insects. These lizards’ natural predators are Arboreal Colubrid snakes, Hornbills and Civet cats. When a danger appears this lizard suddenly climbs in to a tree on average 15 m high and then glides to another tree which 1 m away till the danger disappears. If there is no another tree to glide they just jump down to the ground and stay few minutes without moving, then suddenly run in to another tree (Karunarathna & Amarasinghe, 2008). 

The female digs a nest hole in the ground and deposits about 4-12 eggs in August to October on shady places near from the tree bases. While laying eggs the females change their body color in to black. The eggs are 13.5 mm - 17.1 mm long and 7.8 mm – 8.9 mm wide.  Hatchlings come out from November to December (Deraniyagala, 1957; Karunarathna & Amarasinghe, 2008).

Hatchlings mostly waiting for their preys on Lantana camera (an invasive plant to Sri Lanka) trees while camouflaging their snout color in to pink (the flowers of L. camera are also pink). They specially feed on insects, while feeding on L. camera (Karunarathna & Amarasinghe, 2008).
 
Conservation status: Rare (Manamendra-Arachchi & Liyanage, 1994), Least Concern (Bahir & Surasinghe, 2005) and Vulnerable (IUCN, 2007).