CARL MARSHALL: The Unicorn Gecko

In the October of last year, we were donated an unusual little gecko that not only had cryptozoological cogitations because it was non-native and found in Warwickshire, but when closely examined it actually appeared to have a single horn almost central on top of its head (it was actually offset slightly to the right - see images). Of course this wasn't a legitimate horn as there was no bony core present, rather it was simply the location of a previous injury that had already healed, producing a horn-like protrusion or "pseudo-horn" from the damaged head scales, re-forming a flap of fairly solid tissue. However at a quick glance, at least at certain angles, an observer could easily yet erroneously think they had briefly witnessed a single horned (Unicorn) gecko. It does initially look quite convincing and to add to the would-be confusion, arboreal gecko's are lightening fast when making a fleeting getaway. Maybe certain other mystery reptiles such as crested snakes and cryptid horned snakes have their origins in this type of injury, especially if they were cryptic species of Boids and Pythons as they have similar granular-like scales on top of their heads that can readily re-form in this fashion. However I personally consider retained shed on the head and nape, building up over successive moults in unhealthy individuals, as a possible identification for many of the worlds crested snake reports.      

Although its exact provenance is unknown to us, I think this is probably Hemidactylus sp. (formerly Cosymbotus), a house gecko from Asia that is most commonly referred to as the flat tailed house gecko. What was once an entirely Asian species has now however colonised some of north America since being unwittingly introduced into Florida and finding the sun shine state to their liking. So this individual may have been imported accidentally here from the United States rather than directly from Asia.

Like most true arboreal gecko's Hemidacylus sp. are superb wall-crawlers. These lizards can easily scuttle up sheer surfaces and cling to ceilings effortlessly, thanks to the evolution of toes that are covered with microscopic hairs. Each of these hairs, known as setae, finishes in literally hundreds of even finer spatula-shaped split ends known as spatulae. These ends make intimate contact with the latent bumps and troughs on a given surface, and stick using the same forces that bind individual molecules together. These forces singularly are weak, but summed up over millions of hairs they're enough to stick a gecko to a surface.         

No phylogenetic study's have been made to ascertain whether this widespread species represent unique lineages in the Philippines. 

This charming little gecko appears to be in good health, displaying good body weight with no film on its eyes and they're not hollow or sunken back into the skull either. There are also no other signs of Respiratory infection (RI) and so far its "horn" is still firmly attached.

We have not definitively identified this gecko as Hemidacylus sp. so if any blog readers have any other ideas as to the identity of this little reptile please post a comment.