Hemitheconyx

Hemitheconyx is a genus of geckos in the family Eublepharidae, commonly known as eyelid geckos. The genus name is derived from the Greek words "hemi" meaning half, "theke" meaning case, and "onyx" meaning claw, referring to the partially enclosed eyes and clawed digits characteristic of these lizards. There are currently two recognized species within this genus: Hemitheconyx caudicinctus and Hemitheconyx taylori.

Hemitheconyx caudicinctus, the African fat-tailed gecko, is the more widely known species. Native to West Africa, it is found in arid and semi-arid regions. These geckos are nocturnal and fossorial, spending their days in burrows or under rocks. They are characterized by their stout bodies, large heads, and distinctive fat tails, which they use for storing fat reserves. Their coloration typically includes brown or grayish bases with darker bands or spots.

Hemitheconyx taylori, the East African fat-tailed gecko, is found in East Africa, inhabiting similar arid environments. It is less commonly encountered and kept in captivity compared to its West African relative. Morphologically, it shares many similarities with H. caudicinctus, though subtle differences exist in scale arrangement and coloration patterns.

Both species are insectivorous, feeding on a variety of invertebrates. In captivity, they are popular pets due to their relatively docile nature and manageable size. Their care requirements typically involve a dry, sandy substrate, hiding places, and a temperature gradient. The genus Hemitheconyx is distinguished from other Eublepharidae by specific anatomical features, including their unique eyelid structures and the morphology of their hemipenes in males.