Chioninia coctei


Chioninia coctei, also called the Cape Verde giant skink, Bibron's skink, lagarto, or Cocteau's skink, is a species of lizard, a reptile that was at one time known to inhabit the islets of Branco and Raso in the Cape Verde islands of the Atlantic Ocean, rendered deserts by human-caused habitat destruction. None have been observed since the early 20th century.

Taxonomy

The specific name, coctei, is in honor of French physician and zoologist Jean Théodore Cocteau.
It has been found through mitochrondrial DNA sequences that C. coctei was most closely related to the skink genus Mabuya.

Description

It was very large for a skink. Adults could attain a snout to vent length of, and the cylindrical tail was as long as the head and body.

Behaviour and ecology

It was largely herbivorous, but whether out of necessity with deteriorating conditions or from opportunistic advantage, occasionally became more carnivorous as individuals would occasionally eat the young from nesting shore birds. German herpetologists had noted Macroscincus consuming birds in captivity in the early 20th century.
One interesting aspect of this species is that it possessed a transparent lower eyelid; possibly to spot predators from below.
From the examination of preserved specimens, it appears that this species had a "belly button" slit, indicating viviparity. However, there are also reports that indicate this species was an egg layer.
It is considered unique among the Scincidae in having tooth crowns which are labiolingually compressed and multicuspate.
It had a SENI value of 0.13. As such, it was a partially arboreal skink that was borderline enough to adapt to the semi-desert like conditions created when the Cape Verde islands were denuded by humans and domesticated animals centuries ago.

Extinction

Causes cited for their decline include over hunting for food and use for "skink oil" by natives of neighboring islands and prolonged drought. At one time, starving convicts were marooned in the Cape Verde archipelago and ate the extant population. An explorer, Leonardo Fea, brought back several specimens which are now housed in Italy. This constitutes the extant specimens. Subsequent explorers such as Sheliech, Andreone, and Pather, have failed to find living individuals and has not been found since 1940. In the early 20th century, German herpetologists tried to captive-breed this species to no avail.
In the 2013.1 version of the IUCN Red List, the IUCN declared it officially extinct.