Reptiles and amphibians are two groups of animals well represented in rainforest regions. Amphibians (frogs and toads) are the smallest group of vertebrate animals - they are well represented in the rainforests, mainly because they prefer moist environments. Most amphibians have to live near water in order to breed.
Reptiles include the turtles, snakes, lizards and crocodilians. Rainforest members of this group include many types of snake and lizard, particularly tree-dwelling species. Crocodiles and alligators also live in rainforest rivers.
Chameleons
Chameleons live in the Old World, particularly in the rainforests of India, Africa and Madagascar. These lizards live in trees and shrubs and have prehensile tails and modified toes which help them grip branches. Chameleons eat insects, spiders and scorpions, which they catch by extending the long, mucus-covered tongue: the mucus ensures that the prey does not escape when the tongue is retracted into the chameleon's mouth. Several of the larger species may supplement their diet with mammals and small birds. Chameleons have excellent eyesight, and can rotate each turret-like eye independently.
Chameleons are well known for their ability to change color to blend in with their surroundings: they do this by modifying the amount of skin pigment released at any time - the color change may be used to confuse either prey or the chameleon's own predators. Chameleons also use a 'perch release' reaction, as a defense against predators: when disturbed, the chameleon drops to a lower branch or to the ground.
There are around 85 species of chameleon, including the African chameleon shown in the video clip on this page.
Chisel-teeth lizards
Chisel-teeth lizards belong to the family called the Agamidae. These are Old World lizards, with around 300 representative species in Africa, India, SE Asia and Australia. The name comes from the blunt shape of these lizard's front teeth.
Chisel-teeth lizards eat insects and eggs. They include the flying dragons of SE Asia. These lizards have a thin fold of skin on each side of the body extending from the front to the back legs: they use this skin fold as a parachute, with the tail acting as a steering device. Flying dragons can glide up to 20 feet when moving between trees.
Coral snakes and cobras
This group of snakes (also including mambas and kraits) are sometimes called front-fanged snakes, as they have short, tube-shaped fangs along which runs quick-acting venom. The venom acts on the nervous system and is usually more toxic than that of the vipers.
Cobras live in the forests of Africa, India and Asia and eat frogs, snakes and some rodents. They have a 'hood' made of neck ribs which is extended when the snake is disturbed. The spitting cobra spits venom up to 30 feet into the eyes of its prey, sometimes causing blindness.
Kraits are smaller than cobras and kill many people each year in SE Asia.
Mambas are venomous African snakes: the best known are the black and green mambas. The green mamba is found in rainforests and is less aggressive than the black form.
Coral snakes are found in SE Asia and the New World, and are easily recognised by the bold black, yellow and red bands along their bodies. Although they are venomous, the venom is not injected easily, and the snake often has to inflict multiple bites to kill or disable its prey.
Crocodilians
Crocodilians are closely related to the extinct dinosaurs: they have more advanced internal features than other reptiles and are characterised by their huge jaws, laterally compressed tail and relatively weak limbs. The limbs can however lift the crocodile well above the ground, unlike lizards which have a more sprawling gait.
Crocodilians are found throughout the tropical and subtropical regions of the world. There are 22 known species, split into alligators, crocodiles and the single species of gharial.
The alligators also include the caimans, notably the black caiman and the spectacled caiman of the Amazon basin. The black caiman is one of the largest South American predators, reaching over 30 feet in length - it is known to eat human flesh. Black caimans live in lakes and swamps rather than on main rivers: they have been hunted to the edge of extinction for their hides.
True crocodiles have a longer, more pointed snout than alligators. They live in the rivers of Africa, India and SE Asia. Crocodiles prey on a variety of animals including fish, birds and mammals.
Geckos
Geckos are found in both Old and New Worlds: they are lizards that have ridged pads on their feet that enable them to run up and down vertical surface.
The name 'gecko' may derive from the noise that these lizards make when they click their broad tongues against the roof of their mouths.
Most geckos are active at night and have large eyes to help them see in reduced light intensitiies. They are also rather drab colored. The fewer daytime gecko species are more brightly colored.
Iguanas
Most iguanas live in the New World, although a few live in Madagascar and Fiji. There are over 650 species, including ground and marine iguanas, anoles, horned lizards and basilisks.
Rainforest iguanas include the Green Anole, Common Iguana and Basilisk lizard. The Common Iguana is green when young, but turns into a 5 foot long grayish black adult. Although they are large, these lizards eat mainly fruit.
Much smaller is the six inch long Green Anole. These lizards can change color, rather like chameleons. The males have a bright red dewlap or throat skin, and eat small insects.
Basilisk lizards are 2-3 feet long and have a skin 'sail' on their backs. They eat animal and plant material and are very fast runners. Basilisks have lobed toes fringed with scales, which enable them to run over the surface of water
Leptodactylid frogs
Leptodactylid frogs are found only in Central and South America. They are wide-mouthed toad-like animals looking rather like true toads. Some species live wholly on land, whilst others are aquatic.
The Brazilian horned toad Ceratophrys cornuta shown here gets its name from the horn-like growths of skin that project from its upper eyelids. These toads eat anything small that moves - including fingers if the animal is not handled carefully.
Monitors
Monitor lizards vary in size from the 5 inch long short tailed monitor to the 6 foot Komodo dragon, the largest living lizard. Monitors live in both dry and rainforest environments: they are found in Africa, India, SE Asia and Australiasia.
Narrow mouthed frogs
Narrow mouthed frogs are widely distributed in the Old and New World tropics, and include species which are ground dwelling and others which live in trees. The tree-living species have pads on their toes to help them climb branches, while the terrestrial species often burrow.
Some members of this group lay eggs in water and others lay their eggs in water held in the 'vase' of bromeliad plants. Examples are the answering frogs, a group with a characteristic trill-like call, and the rain frogs. Rain frogs are stout bodied frogs that only appear above ground during heavy rain.
These frogs show special adaptations for climbing. They have loose skin on their undersurface which helps them stick to vegetation, they have toe-disks used for suction, and they also have flattened bodies.
Old World tree frogs
Tree frogs include Wallace's flying frog, a strange frog with areas of webbing between its digits which enable the frog to glide long distances between trees in Borneo and Malaysia. These frogs are 'foam nesters' meaning that they build nests made of fluid secreted and subsequently whipped into foam by the female.
Poison arrow frogs
Poison arrow frogs are small brightly colored frogs which live in the rainforests of Central and South America. They are not aggressive animals, but have toxins in their skin glands which protects them against predators. Indigenous people use these secretions as poison to tip darts or arrows.
Poison arrow frogs show complex social behavior and are often territorial, protecting their territory by attacking other frogs or by calling or changing color.
Pythons and boas
These snakes are sometimes called primitive snakes because they have more lizard-like features than other groups of snake. All pythons lay eggs rather than giving birth to live young. They are not venomous, and these snakes kill their prey by constriction.
Pythons are widely distributed in the tropics of the Old World, feeding on mammals and birds which they kill by constriction. Some live in trees, whilst others are burrowers.
Boas are found in SE Asia and Africa as well as in South America. The Boa Constrictor is found from Mexico down to Argentina and hunts birds and small mammals, usually at night. Its brown and tan coloration provide good camouflage for the forest floor.
The 6 foot long Emerald Tree Boa is bright green in color and as its name suggests lives in trees. These snakes eat birds and rodents, including agoutis and pacas.
Anacondas are boas which live in the rainforests of South America, usually close to water. Anacondas are good swimmers and often float motionless in river currents. They eat turtles, birds, caimans and mammals, and hunt at night. These snakes often lie in wait for their prey to come to the water's edge to drink: they bite the prey and drag it under water where it drowns.
Anacondas up to 37 feet long have been recorded. Like other boas, anacondas give birth to live young, often as many as 40 in a single litter.
Skinks
These lizards are found in a variety of Old and New World habitats, from sandy deserts to rainforests. Skinks have short legs and sometimes have brightly colored tails when young: the tail can be shed when the animal is attacked, and the colored tail acts to confuse the predator.
Most skinks are ground-dwellers, except for the prehensile-tailed giant skink of the Solomon Islands, and the Green-blood skink, unusual for its green blood pigment.
True toads
Toads are mainly ground-dwelling and often burrow or shelter in holes made by other animals. The Marine toad lays up to 20,000 eggs per clutch, and is very large - up to 9 inches long. It is a slow moving animal which inhabits the rainforest floor, and is protected by skin glands which produce a poisonous secretion.
The poison from this toad is produced by paratoxic glands behind the head, and can be squirted up to 3 feet. Several cases of human fatalities have been reported in Fiji and the Philippines from eating Marine toads.
True tree frogs
True tree frogs have flattened, slender bodies which helps them cling to leaves and branches. They live in both Old and New Worlds in temperate and tropical regions.
True tree frogs include the leaf frogs: large, brightly colored amphibians living in lowland and montane rainforests of South and Central America.
Vipers
Vipers are snakes with a single pair of long hollow fangs through which they inject venom. Unlike the neurotoxic venom of the cobras, viper venom acts on the blood and tissues of the animal's victim.
Rainforest vipers include the bushmaster, Fer-de-lance and Gaboon viper. The bushmaster of South and Central America is the longest viper, measuring up to 12 feet. It it the only American viper to lay eggs.
The Fer-de-lance is a smaller American viper and like the bushmaster is termed a 'pit viper' because of the pits in front of the snake's eyes, used to detect the body heat of the snake's prey.
The largest tropical African viper is the Gaboon viper, one of the most dangerous African rainforest snakes. Like the Boa Constrictor, the Gaboon viper hides among the fallen leaves of the forest floor. Its triangular head holds a pair of poison fangs around 2 inches long.
The Philippine Habu Trimeresurus flavomaculatus is an Old World pit viper related to the New World rattlesnakes. Pit vipers have heat sensitive pits on the sides of the head which enable them to track warm-blooded prey.
Rattlesnakes themselves also belong to the viper family, and a number of species are found in rainforest environments. The neo-tropical rattlesnake lives in Central and South American rainforests.
