The family Agamidae is confined to the old world and the majority of genera occur in the oriental region. Agamids can be separated from all other Oriental lizards by the nature of their teeth. These are divided in to incisors, canines and molars (Daniel, 2002). The Family Agamidae is distinguished from other families by having a compressed body and dorsinuchal crest, distinct neck, well developed eyes with eyelids, pupil round, Short and thick tongue, a compressed gular sac, an exposed or sub dermal tympanum, well developed Limbs and an elongate, compressed or rounded tail (Daniel, 2002; Deraniyagala, 1953).
Agamid Lizards are arboreal, sub arboreal or terrestrial (Deraniyagala, 1953). As among other lizards the shape of the body is indicative of the habit, arboreal forms are flattened laterally and ground-dwelling forms are flattened dorso-ventrally (Daniel, 2002). And they are capable of rapid color changes (Deraniyagala, 1953).
During the breeding season, the male is brilliantly colored in many species (Daniel, 2002). Their Reproduction is ovoviviparous or oviparous with hard or soft-shelled elliptic eggs (Amarasinghe & Karunarathna, 2007, 2008; Deraniyagala, 1953; Pradeep & Amarasinghe, 2009). Females lay eggs of varying sizes depending upon the ecological conditions (Dunham et al., 1988; Sinervo, 1990) and breeding time especially in species with multiple clutches (Shanbhag, 2002, 2003).
The majority of Agamids are insectivorous. A few are carnivorous (Daniel, 2002), sitting in wait for appropriate-sized insects to come within striking distance (Das & de Silva, 2005).
Usually Agamid lizards thermo regulate in the morning and in the evening by sun basking (Pough et al., 2004) and in the absence of solar radiation, metabolic heat production is the only way to increase the heat gain, but it is more economical to use an external source rather than body fuel (Schmidt-Nielsen, 1995). According to Karunarathna & Karunarathna (2005) some agamid species thermo regulate by lying on the roads at night.
|
