Common sandfish, Common skink
The Sandfish skink (Scincus scincus) is a species of lizard known for its burrowing or swimming behavior in the sand. It is native to the Sahara Desert and the Arabian Peninsula but is also kept as a pet elsewhere.
Adult Sandfish skinks usually reach about 20 cm (8 inches) in length, including the short tail. It has a long, wedge-shaped snout with a countersunk lower jaw, shaped much like a basket. Its compact, tapered body is covered with smooth, shiny scales that may appear oily to the untrained eye, and its legs are short and sturdy with long, flattened, and fringed shovel-like feet. The tail is short, tapering to a fine point. The coloration of this species is considered attractive, being yellow caramel with brown-black cross bands. This lizard also has bead-like eyes so it can close them to keep sand out of its eyes. Similarly, its nostrils are very small to keep all of the sand out of its nose and lungs.
Sandfish skinks are found over an extensive belt of the desert from the west coast of Africa, through the Sahara, and into Arabia.
Sandfish skins are solitary diurnal creatures. They spend most of their time burrowing in sand and thus have developed a peculiar surprise way of dealing with the desert heat: they can dive into the loose, soft sand. Their winding movements produce vibrations in the sand, with a consistent frequency of 3 Hz. Sandfish skinks do this to prevent overheating (as they are cold-blooded) and whenever they feel threatened, especially by the arch-nemesis, the devil-headed Saharan snake. When hunting, Sandfish skinks can detect vibrations that nearby insects create while moving, using those vibrations to locate, ambush, and consume them. These lizards swim within sand using an undulatory gait with their limbs tucked against their sides rather than using their limbs as paddles to propel themselves forward. Sandfish skinks are also able to breathe even when completely submerged in the desert sand. They breathe the tiny pockets of air between grains of sand, and a specially-formed respiratory tract catches inhaled particles before they reach the lungs. These particles are then expelled via sneezing.
Sandfish skinks are carnivores (insectivores). Their diet consists of dubias, crickets, and mealworms.
Little information is known about the mating system and reproductive behavior of this species. It is known that their breeding season takes place from May to June and the average gestation period is 3 months.
There are no major threats to the Sandfish at present. However, they may be collected locally for the pet trade.
According to IUCN Red List, the Sandfish skink is locally common and widespread throughout its range but no overall population estimate is available. Currently, this species is classified as Least Concern (LC) on the IUCN Red List and its numbers today are stable.