On Friday I gave you this object to identify:

I must admit that I thought it would be a tricky one, but I was surprised by the number of correct answers that came in, with the first by Prancing Papio who immediately got it to species. Neil made a subtle comment (“Looks like it could go both ways“) that almost passed me by, but which indicated that he knew which group this skull belonged to (see below for elucidation), whilst David Craven and Jamie Revell both pinned it down to species as well. That identification was the Smallhead worm lizard Leposternon microcephalum Wagler, 1824.

These bizarre reptiles are found in Brazil and they are a member of the Amphisbaenia – a group of (mainly) legless burrowing lizards. The name Amphisbaenia comes from a mythical beast with two heads called the Amphisbaena, a name that is derived from the Greek meaning “to go both ways” (hence Neil’s comment). They get this name because they have a very rounded tail that looks just like the head of this odd animal. This particular species has a very shovel-shaped head that it uses to excavate tunnels (how they do it is described briefly in this pdf). They move very differently to snakes and although they are superficially similar in their body shape and lifestyle to the blindsnakes they are not closely related at all. Indeed, they are also superficially similar to the Caecilians, which are legless burrowing amphibians – an example of convergent evolution.

The biology of these tiny reptiles is not very well known – living mainly underground makes them hard to study. There is a brief documentary on them here, in which it’s worth noting the section that states there is a ‘belief’ in their healing properties. Are they a source of medicine for the future or is it just superstition? I’ll withhold judgement until reliable research is carried out.

Finally, here is a photo to give you an idea of what they look like in the flesh (and I warn you now that they’re not pretty…)

Small headed worm lizard, Leposternon microcephalum, by Chris Knowles