Oriental garden lizard

The oriental garden lizard, also known as the eastern garden lizard, Indian garden lizard, common garden lizard, bloodsucker, or changeable lizard, is an agamid species native to the Indo-Malayan region. It has also been introduced to other parts of the world.

Description

This insectivore measures over 10 centimeters from snout to vent, with a total length including the tail reaching up to 37 centimeters. Above each ear opening are two separate clusters of spines. The dorsal crest is moderately raised on the neck and front part of the body, extending onto the tail base in large adults, while in younger individuals it gradually fades along the middle of the back. There is no fold in front of the shoulder, but the scales behind the lower jaw are noticeably smaller than others, and the throat pouch is not developed.

Around the middle of the body, there are 39 to 43 rows of scales. In adults, the hind foot is not much longer than the head, but in juveniles it is considerably longer. Coloration varies widely—sometimes uniform brown, greyish-olive, or yellowish.

Often there are broad brown bands across the back, broken by a yellowish side stripe. Black streaks radiate from the eye, some continuing obliquely backward across the throat. The belly frequently shows greyish longitudinal lines, with one along the midline being most distinct. Young and half-grown lizards have a dark, black-edged band across the area between the eyes.

The ground color is usually light brownish olive, but the lizard can change it to bright red, black, or a mix of both. This color shift may be limited to the head or spread over the entire body and tail. A common sight, as noted by T. C. Jerdon, is the lizard perched on a hedge or bush with its tail and limbs black, head and neck yellow with red accents, and the rest of the body red.

Jerdon and Blyth agreed that these bright, changeable colors are exclusive to males during the breeding season, which runs from May to early October. Albert Günther noted that Alexandre Henri Mouhot collected one of these fine color variations in Siam, though they appear endless. The species has the usual cross streaks between the eyes and radiating lines, ranging from continental India to China. It is very common in Sri Lanka, where specimens are generally larger—one measured 16 inches, with the tail accounting for 11 inches.

It lives in hedges and trees. In Sri Lanka, it is called "Bloodsucker," a name whose origin is unclear; Kelaart believed it came from the occasional reddish hue of the throat and neck. In Bengali, it is also known as "Roktochosha," which translates to "bloodsucker."

The female lays five to sixteen soft, oval eggs, about 5/8 of an inch long, in tree hollows or holes in the soil she has burrowed, then covers them. The young emerge in about eight to nine weeks. On a hot, sunny day, a solitary bloodsucker may be seen basking on a twig or wall with its mouth wide open.

After a rain shower, many come down to the ground to pick up larvae and small insects that have fallen from the trees. They escape danger by darting to the nearest tree; if a predator gets closer, they scale the side facing away and swiftly climb up, leaving the predator looking behind the tree only to find the lizard already in the branches. During the breeding season, the male's head and shoulders turn bright orange to crimson, and his throat becomes black. Males also develop a red head after a successful fight with rivals.

Both sexes have a crest from the head nearly to the tail, giving them the other common name "crested tree lizard." Unlike some lizards, they do not drop their tails (autotomy), and their tails can be very long, stiff, and pointed. Like other reptiles, they shed their skin. Like chameleons, they can move each eye in different directions.

Distribution

The species' native range includes southeastern Iran, Afghanistan, Bangladesh, Bhutan, Cambodia, India (including the Andaman Islands), Indonesia (Sumatra), Malaysia (western), Maldives, Mauritius (Reunion, Rodrigues), Myanmar, Nepal, Pakistan, Philippines, Sri Lanka (Ceylon), Thailand, and Vietnam (including Pulo Condore Island). It has been introduced to Brunei, Celebes, Oman, Seychelles, Singapore, and the United States. The lizards were introduced to Singapore from Malaysia and Thailand in the 1980s, where they threaten the native green-crested lizard.

The changeable lizard is relatively common and found in a wide range of habitats, adapting well to humans and thus not endangered. It is commonly found among undergrowth, in open habitats, and in highly urban areas. However, in China, people regularly kill them, viewing them as pests.

Diet

Changeable lizards eat mainly insects such as ants, beetles, dragonflies, and grasshoppers, as well as small vertebrates including rodents and other lizards (agamids, geckos, and lizards). Their teeth are designed for gripping prey, not tearing, so they usually shake prey to stun it and then swallow it whole.

Sometimes young, inexperienced lizards may choke on prey that is too large. They also occasionally consume plant matter. Males become highly territorial during the breeding season and discourage intruding males.