It's normal for reptiles to shed their skin as they grow, plus many lizards are capable of breaking off and regrowing their own tail, in order to escape predators. The newly-described Geckolepis megalepis gecko, however, possesses a trait that sits somewhere between the two. When a predator tries to eat it, that creature often just ends up with a mouthful of tear-away scales.
Although such "fish-scale" geckos have been known of for some time, scientists from Germany's LMU Munich (Ludwig-Maximilians-Universität Munich) and Zoologische Staatssammlung München (The Bavarian State Collection of Zoology) only recently discovered that Geckolepis megalepis is a separate species. One of the things that sets it apart is its exceptionally large scales.
Like other members of the genus Geckolepis, it's able to shed those scales when attacked. This is because a narrow strip of skin is all that keeps each scale attached to the body, and that strip already has a "splitting zone" built into it. As a result, even if the lizard is simply touched, it can release the scale.
In the case of Geckolepis megalepis specifically, the scales are particularly good at coming off. This is likely because of how large their surface area is relative to the attachment area, along with the extra friction surface provided.
Once an area of scales has come off, the smooth skin underneath is left exposed. That situation doesn't last for long, though, as new scales grow back to cover it within a few weeks.
"What's really remarkable though is that these scales – which are really dense and may even be bony, and must be quite energetically costly to produce – and the skin beneath them tear away with such ease, and can be regenerated quickly and without a scar," says LMU's Mark D. Scherz, who led the research along with Dr. Frank Glaw.
It is now hoped that a better understanding of that regeneration mechanism could eventually have applications in human medicine.
A paper on the research was recently published in the journal PeerJ.
Source: LMU Munich
