Geckos

Geckos 

(Gekkonidae), a family of reptiles in the order of lizards. They normally have large eyes with vertical pupils, usually without movable eyelids. Only a few geckos are more than 30 cm long. The legs are always well developed. Most geckos have broadened toes with horny plates on the bottom. Microscopic hairs covering the plates and sharp claws enable geckos not only to hold onto vertical surfaces but even to run along them. With rare exceptions the tail is very brittle, but it is rapidly restored (regenerated). Most geckos are colored in gray or brown tones, but brightly colored geckos are also encountered among the tropical forest types.

Geckos are twilight and nocturnal animals. Most geckos hold onto trees, cliffs, banks, and similar vertical surfaces. Geckos that live in deserts usually dig holes in which they hide during the day. They eat insects, spiders, centipedes, and so on. Many geckos produce quiet noises. Almost all geckos are oviparous. Gecko eggs have a hard calcareous shell. There are one or two eggs to a clutch. During the season eggs are laid several times.

There are about 70 genera comprising some 480 species. Geckos are distributed in the tropical and subtropical zones and, to some extent, in the temperate zone. There are eight species of geckos in the USSR, primarily in Middle Asia and Kazakhstan. The scincoid gecko (Teratoscincus scincus) and the comb-toed gecko (Crossobamon eversmanni) are typical inhabitants of the sand deserts of Middle Asia. One species from the genus of bare-toed geckos, the gray bare-toed gecko (Gymnodactylus russowi), is also found in the Crimea and Transcaucasia. Gecko fossils have been found dating as far back as the Eocene period.

REFERENCES

Terent’ev, P. V. Gerpetologiia. Moscow, 1961.
Underwood, G. “On the Classification and Evolution of Geckos.” Proceedings of the Zoological Society of London, 1954, vol. 124, part 3, pp. 469-92.