Technology & Science

New species of gecko sheds scales, skin to avoid predators

Scientists have found a new species of gecko that sheds its large, fish-like scales — and part of its skin — in order to avoid being eaten by predators.

Geckolepis has the largest scales of any known gecko

The newly discovered Geckolepis megalepis has the largest body scales of all geckos. (F. Glaw)

Scientists have found a new species of gecko that sheds its scales — and part of its skin — in order to avoid being eaten by predators.

This type of gecko, which was discovered in Madagascar, belongs to the genus Geckolepis, a group known for the ability to shed their large fish-like scales. But this new species — Geckolepis megalepis — has the largest scales known. It's also a pro at shedding.

The scales of the gecko are only attached by a narrow region as well as a splitting zone in the skin, which allows them to shed easily. 

Other species that are able to do this usually do it only when grasped firmly, but Geckolepis megalepis do it at the slightest touch. They're also able to regrow their scales rather quickly compared to other species, taking just a few weeks.

When grasped by a predator, the geckos lose not just their scales but also the skin underneath. (F. Glaw)

But here's the challenge: how do you study something that loses its scales at the slightest touch? 

"You have to think a bit outside the box with Geckolepis," Mark D. Scherz, lead author of a study on the species and PhD student at the Ludwig Maximilian University of Munich and Zoologische Staatssammlung München, said in a statement. "They're a nightmare to identify."

One of the ways to tell gecko species apart is by looking at scale patterns. But when a gecko sheds its scales so easily, that makes it a bit of a challenge.

The researchers instead used a micro-CT scan — which provides a 3D X-ray — to examine their skeletons. They found various features that distinguished them from other geckos. They also discovered that a species identified 150 years ago (Geckolepis maculata) didn't belong to the genetic lineage scientists once thought it did. 

"This is just typical of Geckolepis," Scherz said. "You think you have them sorted out, but then you get a result that turns your hypothesis on its head."

The study was published in the journal PeerJ.