Saturday, 30 December 2023

29-12-2023 NGALA LODGE, GAMBIA - RAINBOW AGAMA (Agama agama)

Rainbow lizards can occupy urban, suburban and wild areas that supply enough vegetation for reproduction and insects for food.

The agama lizard is characterized by its whitish underside, buff brown back limbs and tail with a slightly lighter stripe down the middle and six to seven dark patches to the side of this stripe. There is some sexual dimorphism. The subordinate males, females, and adolescents possess an olive green head. A blue body and yellow tail and head characterize the dominant male. A. agama has a large head separated from the body, a long tail, well-developed external ear openings and eyelids. This lizard also has acrodont, heterodont teeth. The lizard possesses both caniniform incisors for grasping and molariform cheekteeth for crushing. The maximum size for male lizards is twenty-five centimeters and female lizards is twenty centimeters (Harris 1964).

Females reach sexual maturity at age fourteen to eighteen months, males at two years. A. agama reproduces during the wet season although they are capable of reproducing nearly year round in areas of consistant rainfall(Porter et al. 1983). The male will approach the female from behind and head bob to her. If she accepts then she will arch her back with her tail and head raised. The male walks to her side and grasps her neck and puts his leg on the female's back, the pair swivel 90 degrees in order to bring their cloacas together and thrusts his tail onto her cloaca inserting his right or left hemipenes (depending on side location). This mating ritual usually lasts one to two minutes when the female will scurry away and the male also after several minutes (Harris 1964).

The female lays her eggs in a hole she digs with her snout and claws. The hole is five centimeters deep and is found in sandy, wet, damp soil that is exposed to sunlight nearly all day and covered by herbage or grasses. The eggs are usually laid in clutches ranging from five to seven ellipsoidal eggs. A. agama is a thermoregulated embryo species resulting in all males at twenty-nine degrees Celsius and all females at twenty-six to twenty-seven degrees Celsius (Crews et al. 1983). The eggs will hatch within eight to ten weeks. Hatchlings will be between 3.7 and 3.8 centimeters snoutvent plus their 7.5-centimeter tail. They will almost immediately start eating rocks, sand, plants, and insects. The adolescent will remain solitary for the first two months and by four months live in a gregarious group with a dominant male (cock), several females and some subordinate adolescent males (sub-males). The dominant male has mating distinction within his territory. If a sub-male or intruder tries to mate with his females then there is a challenge or fight. To gain territory males must establish a new territory with no cocks or dispose of the current cock (Harris 1964).


 

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