Tag: Reptiles & Amphibians

Helmeted Basilisk Corytophanes cristatus Photo by Jenn Sinasac The Helmeted Basilisk, also known as the Helmeted Iguana, Casque-headed Lizard and Old Man Lizard, is a small, arboreal lizard found throughout Central America. It has a distinct, specialized head “casque,” well-developed in both sexes, with helmet-shaped raised ridges forming a serrated crest along the back of the head and extending onto the neck and back. At an overall length of 36 cm, its laterally-compressed body is 8-12 cm, with a long tail 2 to 2½ times its body length. It has keeled scales over its entire body, and is typically olive to rich chocolate or reddish-brown in color, with some green. Black lines extend from the eyes to the light colored lip. It has very long toes. With a physical resemblance to African chameleons, it cannot be confused with anything else! Helmeted Basilisks are sit-and-wait predators; they remain motionless on small vertical trunks and branches with their head pointed upward, often for hours at a time, capturing prey infrequently. They allow for close approach, and are often catchable. They feed on slow-moving arthropods, particularly caterpillars and beetle larvae, and occasionally small anoles. They will also hunt on the forest floor. They capture prey infrequently. Helmeted Basilisks have some unique anti-predator behaviors. Their first line of defense is camouflage—they can resemble lichen with spots forming on their skin when resting, and can change color rapidly. They freeze their body, making themselves so rigid as to eliminate all minor movements, a behavior called “cataleptic freezing." If these passive measures fail, they compress their body, erects their crest, expand their gular pouch and bob their head. By doing this, they hope to increase their apparent body size and deter the predator. If all else fails, they will attack and bite ferociously. Breeding occurs throughout

Turnip-tailed Gecko Thecadactylus rapicauda Photo by Jenn Sinasac This interesting Neotropical gecko is immediately recognizable by its large size, with a body length of up to 12 cm, and its large, swollen tail, approximately the same length or slightly shorter than its body; females are larger and more robust than males.  It has short, robust legs with flattened toes and extensive basal webbing.  The undersides of its toes are covered in lamellae, used as friction pads to cling to smooth vertical surfaces.  Turnip-tailed Geckos are variable in coloration, from a mottled dark gray to orange-brown, and are capable of changing color depending on their mood and surroundings.  Mottled and banded markings aid in camouflage against tree bark.  During the day, roosting Turnip-tailed Geckos tend to be a lighter color than at night.  Their pupils are vertical and elliptical in shape, and they have no eyelids.  Turnip-tailed Geckos are nocturnal, and are often found clinging to tree trunks up to 20 m above the ground.  They spend their days concealed in dark tree grooves and cavities.  At night, they vocalize by giving a series of 15-25 chirps and clacks, used for territory establishment and defense.  Turnip-tailed Geckos are insectivorous, and feed on cockroaches, grasshoppers, beetles and spiders.  Their reproductive season is during the rainy season from May to September.  After mating, a female lays 1 or (rarely) 2 eggs which she buries in slightly moist substrate or deposits in a tree trunk.  Young hatch 13 days later. Turnip-tailed Geckos use their large tails for a few different uses.  The tail is primarily used in fat storage.  They wave their tail when threatened to show aggression.  They can also shed their tail to distract predators and avoid being eaten.  In addition to waving their tail when threatened, they may also open their