Smooth helmeted iguana
The smooth helmeted iguana ("Corytophanes cristatus"), sometimes also known as helmeted iguana, helmeted basilisk, elegant helmeted lizard, etc., is a species of New World lizard in the family Corytophanidae. Taxonomic history. Etymology. The smooth helmeted iguana is named for the prominent casque, or crest on the back of its head and neck which has the appearance of a helmet. Evolutionary history. The Corytophanidae family of lizards is thought to have Euramerican and Laurasian ancestral beginnings, and is believed to have moved down to the tropics after the Eocene period cooling, approximately 33–56 million years ago. Geographic range  and habitat. It can be found ranging from Chiapas in southern Mexico to north-western Colombia. The habitat they primarily occupy in this range are primary and secondary mesic rain-forest. These iguanas live predominantly in trees, but also hunt on the forest floor where they use leaf litter as a micro-habitat. Description. The smooth helmeted iguana is a medium sized lizard with long slim legs and very long toes. It can be grey, olive, brown, black or reddish-brown with irregular blotches. The smooth helmeted iguana can change the color of its skin as a method of camouflage . As indicated by its name, the smooth helmeted iguana has a prominent crest on its head, which tapers to a saw-tooth ridge down its back. The crest is present in both males and females of the species, though the crest is larger in males. These iguanas are approximately in size when mature. They are a non-heliotherm species, meaning that they do not use the sun to increase their body temperature. Rather, they maintain their body temperature at around , close to the temperature of the forest floor habitat where they live. These lizards are very wary of predators and  freeze at the approach of danger from up to away. Behavior and ecology. Reproduction. Females lay five to six eggs in a depression on the forest floor. It is speculated that the crest on their head may be used in excavating the nest. Diet. "Corytophanes cristatus" feeds on insects, spiders, worms, and other lizards. These organisms are extreme "sit and wait" predators and their foraging is brief and infrequent. Therefore, these lizards are considered to be opportunistic feeders. They are also specialist feeders that prey on extremely large arthropods and cicadas when available. If the lizard has no luck being  a sit and wait predator, they will sometimes become active predators and look for their next meal. Typically, if this is the method they choose they will choose prey that is slow and easy to capture. Interactions with algae and fungi. The smooth helmeted iguana has been observed to remain motionless for extended periods of time. It is thought that this behavior has resulted in their skin being used as a novel growing substrate for a species of fungus, "Physarum pusillum". This species of lizard is also the only known vertebrate observed with a cormophytic plant growing on it. Color  change. The smooth helmeted iguana, like chameleons and other iguanas, has the ability to change its coloration from dark to light or "vice versa", which aids in thermoregulation when basking in sunlight. Conservation. The smooth helmeted iguana is common and widespread throughout its native range. There are no current conservation concerns for this species although deforestation can be a localized threat to smooth helmeted iguana populations.