New gecko species gets ‘naked’ to avoid predators

A newly-discovered species of geckos have a unique method of escaping predators – the unusual creatures can not only detach their tail like other geckos but can also shed their scales in order to escape capture, according to research published Tuesday in the journal PeerJ.

Identified as Geckolepis megalepis, the new species has fish-like scales that are larger than other members of its genus, the Los Angeles Times said, and while other geckos also have scales which can be removed, they lack the level of control that the Geckolepis has over the mechanism.

naked

When grasped, this lizard loses its scales (F. Glaw)

Megalepis was found in the limestone karst of Ankarana in northern Madagascar, according to the study authors, and is the first new member of its genus to be detailed in 75 years. In fact, they were even able to snap an image of a nearly scale-less specimen, which had pink skin and looked like “a fresh, uncooked sausage that is… wet,” the Washington Post noted.

The good news, lead author Mark Scherz, a herpetologist with the Bavarian State Collection for Zoology in Munich, told the Post, is that they can replace the lost scales in a matter of weeks. He noted that the regeneration process “is, as far as we have been able to tell, scarless” and that new scales appear to be “indistinguishable” from the original ones.

Defense mechanism ‘unique among vertebrates,’ scientists say

Informally dubbed “fish-scale geckos,” G. megalepis appear can be removed far more easily than most other gecko scales, according to the Times. This is due partially to their size, but Scherz and his colleagues believe that the lizards use a control mechanism to trigger the process as well.

As the researchers explained, the gecko contracts a layer of connective tissue located beneath the skin in order to release its scales. At the same time, the blood vessels closest to the surface of the skin contract to prevent bleeding, thanks to a specialized type of cell called a myofibroblast.

Myofibroblasts tighten on contact, the Post explained, causing both the upper layers of skin and the subcutaneous fat tissue to loosen, allowing the scales to be easily removed. While Scherz and his colleagues have only seen this defense mechanism used once in the wild, he said that it would be “reasonable to infer that this is a good escape strategy, or else it is unlikely to have evolved.”

While the Times compared the appearance of the scale-less gecko to that of “a half-picked scab,” stem cells from the bottom layers of connecting tissue soon begins regenerating the scales, and it usually takes just a few weeks before the creatures are once again covered in scales. The process is described by the study authors as “unique among vertebrates,” and further analysis could help scientists adapt the mechanisms to help treat humans.

Scherz admitted to the Post that his team doesn’t know a ton about these new creatures yet, but that they are hopeful that they will be able to learn more about this scale-shedding process and its functionality against various types of predators in future studies. Researchers from Sam Houston State University in Texas, and Hessisches Landesmuseum Darmstadt and Technische Universität Braunschweig in Germany were also involved in the study.

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Image credit: F. Glaw