National Zoo – Tokay Gecko

By FNZ
October 20, 2009

Taxonomy
Order: Squamata
Family: Gekkonidae
Genus/species: Gekko gecko

Description
With a length of around 14 inches (35 cm), tokay geckoes are one of the largest geckoes alive today . The body of a tokay is cylindrical, squat, and somewhat flattened on the upper side. The limbs are well-defined and uniformly developed. The head is large and set off from the neck, and they have large, prominent eyes with vertically-slit pupils. The eyelids of these animals are fused together and transparent. They also have a pineal body or “third eye” on the top of their head, which is believed to coordinate their activity with light conditions. The ears can be seen on the outside of the gecko as small holes on both sides of the head. It is possible to see straight through the head of these geckoes through their ears. Their toes that have fine setae on them, allowing them to cling to vertical and over-hanging surfaces and move at fast speeds.

They have soft, granular skin that feels velvety to the touch. The coloration of a tokay gecko is very important to its lifestyle. The skin is usually gray with several brownish-red to bright red spots and flecks but it has the ability to lighten or darken the coloring of its skin. They usually do so in order to blend in or to be less noticeable to other animals.

There are obvious male and female differences in the tokay gecko. The male is more brightly colored than the female and generally the male is slightly larger than the female. A conspicuous difference between the sexes is the small amount of swelling at the base of the tail of the male, due to the presence of the two hemipenes. Also, the males have visible preanal and femoral pores and postanal tubercules.

Tokay geckoes are solitary creatures. They encounter the opposite sex only during the breeding season. They defend their territory against intruders of the same species and of other species, ensuring less competition for food. The territory is generally guarded by males but is occasionally watched by the female. These geckoes can inflict severe bites if they are sufficiently threatened.

The nose is used for breathing and also for detecting scents. Scents are detected by the large number of sensory cells on a membrane in the nostrils. They are also detected by using the Jacobson’s organ. The tokay gecko uses its tongue to carry scent particles to Jacobson’s organ and “taste” the air.

They have folds of skin that prevent the animal from casting a shadow while resting on a tree. They open up the skin fold completely and this allows them to blend in with the tree bark.

An important characteristic of the tokay gecko is its ability to cast off its tail in defense and regenerate a new one. The part of the tail that has been cast off continues to move violently for several minutes until it slows down and stops, thus giving the gecko time to escape. The tail has several sections on it where it can break off. It takes about three weeks for these geckoes to completely regenerate a new tail although it is usually never as long as the original.

Calls of the tokay gecko are used for communication, finding members of the opposite sex during the breeding season, and as a means of defense (they emit a hissing or croaking noise when being attacked).

Tokay geckoes are nocturnal.

Distribution and Habitat
Tokay geckoes are found from northeast India to the Indo-Australian Archipelago.

The tokay gecko lives in tropical rainforests, on cliffs and trees, and as pets among human habitation. They are arboreal and cliff-dwelling. They can travel on floating debris to colonize tropical islands. Tokays form mutualistic relationships with humans in tropical areas — humans provide shelter and tokays provide insect extermination. They can be found doing just this at the Small Mammal House.

Diet in the Wild
Tokay geckoes are insectivorous.

Zoo Diet
In captivity, they usually feed on mealworms, cockroaches, crickets, grasshoppers, pink mice, and locusts.

Reproduction
Around mating season, tokays release a liquid from their femoral pores that is thought to attract a mate or to make copulation easier. The femoral pores are located on the upper hind legs. The breeding season lasts about four to five months. Males copulate frequently with females, often grasping them with their mouths. During the breeding period, females lay eggs every month. In order to attract a mate, a male has a call that can be heard over a wide area. This loud “to-kay” sound is repeated multiple times; this sound gives these geckos their name. The male approaches the female from the rear, and they move side to side while he holds her in place with his teeth, biting her in the neck region.

The female looks for a laying site, and when she finds the right one, she affixes the small, hard-shelled, oval-shaped eggs to a solid foundation where they are guarded by both parents until they hatch. They “glue” their eggs on objects, walls, and packing crates, which has resulted in their being transported throughout the world, becoming established where food and climate are optimal.

Hatchlings are two to three inches (5 to 7.5 cm) long. Upon hatching, the young eat their outer covering of skin. They are sexually mature in about one year. Hatchlings are aggressive and readily bite, just like their parents.

Life Span
Unknown.

Status
There is no special status for tokay geckoes.

Fun Facts
Tokay geckoes eat pests such as cockroaches and locusts. In parts of Southeast Asia, tokay geckoes are regarded as harbingers of luck, good fortune, and fertility.

Source of Information
All or part of this information was provided by the Animal Diversity Web and Museum of Zoology of the University of Michigan.
It appears here with their permission. The original author of this information was Jaime Corl.

For more information, including references, see the Animal Diversity Web account for this species, here:
http://animaldiversity.ummz.umich.edu/ site/ accounts/ information/ Gekko_gecko.html.

Source:  National Zoo

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