''Scincus scincus'', also commonly known as the sandfish skink, common sandfish or common skink, is a species of
skink
Skinks are a type of lizard belonging to the family (biology), family Scincidae, a family in the Taxonomic rank, infraorder Scincomorpha. With more than 1,500 described species across 100 different taxonomic genera, the family Scincidae is one o ...
notable for its burrowing or swimming behaviour in sand. It is native to the
Sahara Desert
The Sahara (, ) is a desert spanning across North Africa. With an area of , it is the largest hot desert in the world and the list of deserts by area, third-largest desert overall, smaller only than the deserts of Antarctica and the northern Ar ...
and the
Arabian Peninsula
The Arabian Peninsula (, , or , , ) or Arabia, is a peninsula in West Asia, situated north-east of Africa on the Arabian plate. At , comparable in size to India, the Arabian Peninsula is the largest peninsula in the world.
Geographically, the ...
,
but is also kept as a pet elsewhere.
Description
The name Algerian sandfish originated because of its ability to move through sand as if it were swimming.
Adult common skinks usually reach about 20 cm (8 inches) in length, including the short tail.
The common skink has developed a unique way of dealing with the desert heat: it can dive into loose, soft sand.
Its winding movements produce vibrations in the sand, with a consistent frequency of 3 Hz.
It does this to prevent its body from overheating and to escape potential predators, such as the Saharan Sand Viper (''
Cerastes vipera'')
This skink 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.
The skink plays a small yet significant role in 13th century Islamic mythology originating in Algeria. To this day, nomadic tribes of the region believe that the skink's ability to avoid predators by diving into sand is a blessing that protects them from dangers of the desert and often keep the animal as a pet.
X-ray imaging
[ ] has demonstrated the lizard swims within sand using an undulatory gait with its limbs tucked against its sides rather than use its limbs as paddles
to propel itself forward. Subsequent studies of the mathematics of sandfish sand-swimming, using robotic models,
and
electromyography
Electromyography (EMG) is a technique for evaluating and recording the electrical activity produced by skeletal muscles. EMG is performed using an instrument called an electromyograph to produce a record called an electromyogram. An electromyo ...
show that the sandfish uses the optimum waveform to move through the sand with minimal energetic cost, given its anatomy.
To further support their title as a "sand-fish," these lizards are 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.
Range
Species in the ''Scincus'' genus are distributed over an extensive belt of desert from the west coast of Africa, through the Sahara and into Arabia.
Diet

The sandfish skink is an
insectivore
file:Common brown robberfly with prey.jpg, A Asilidae, robber fly eating a hoverfly
An insectivore is a carnivore, carnivorous animal or plant which eats insects. An alternative term is entomophage, which can also refer to the Entomophagy ...
. Sandfish have a diet of dubias, crickets, and mealworms. It can detect vibrations that nearby insects create while moving, using those vibrations to locate, ambush, and consume them.
Hardiness
Sandfish are strong and resilient, since one of the most inhospitable places to live is their home. They live comfortably in temperatures of 54 degrees Celsius (130 degrees Fahrenheit) to 32 degrees Celsius (90 degrees Fahrenheit).
Relatives
The sandfish has around 6 or 7
morphs. The sandfish is very similar to
Peters's banded skink, a less wedge-nosed skink with different hands that are more similar to a blue tongue skink than a sandfish.
References
External links
physorg.com Study Reveals Small Lizard Tucks Legs and Swims Like a Snake Through Desert Sand (w/ Video)
{{Taxonbar, from=Q620576
Scincus
Reptiles of Africa
Reptiles of the Middle East
Reptiles as pets
Reptiles described in 1758
Taxa named by Carl Linnaeus
Articles containing video clips