24 New Species of Skinks Discovered on Caribbean Islands

Posted on May 2, 2012

Anguilla Bank Skink


Twenty-four new species of skinks have been discovered on Caribbean islands by a team led by Blair Hedges, of Penn State University, who has described the species scientifically. The picture above is of one of the new species, the Anguilla Bank skink.

About 130 species of reptiles from all over the world are added to the global species count each year in dozens of scientific articles. However, not since the 1800s have more than 20 reptile species been added at one time. Half of these new species already may be extinct or close to extinction. The loss of many skink species can be attributed primarily to predation by the mongoose -- a predatory mammal that was introduced by farmers. Other types of human activity, such as the removal of forests, also are to blame.

Hedges says, "Now, one of the smallest groups of lizards in this region of the world has become one of the largest groups. We were completely surprised to find what amounts to a new fauna, with co-occurring species and different ecological types."

Hedges says these New World skinks arrived in the Americas about 18 million years ago from Africa by floating on mats of vegetation. They are unique among lizards in that they produce a human-like placenta, which is an organ that directly connects the growing offspring to the maternal tissues that provide nutrients.

Hedges says, "While there are other lizards that give live birth, only a fraction of the lizards known as skinks make a placenta and gestate offspring for up to one year."

The researchers believe the mongoose is the main culprit in the reduction of skinks on the Caribbean islands. A graph here from Hedges shows how the skink population has plunged since the mongoose was introduced.

Hedges says, "The mongoose is the predator we believe is responsible for many of the species' close-to-extinction status in the Caribbean. Our data show that the mongoose, which was introduced from India in 1872 and spread around the islands over the next three decades, has nearly exterminated this entire reptile fauna, which had gone largely unnoticed by scientists and conservationists until now."

Photo: Karl Questel, courtesy of Penn State University