Jan 14, 2009

Horror Frog

I've posted on the horror frog, Trichobatrachus robustus, before, but Rachel pointed me towards a fairly in depth article about them. And a new photo. So much to share.

In their native Cameroon, people who eat the horror frog have to hunt them with spears and machetes, as opposed to the usual nets, because these frogs can defend themselves. They do so with the Wolverine-style mechanism seen below.

Photo source: NewScientist.com

When provoked, these frogs flex muscles in their toes that cause a bony spur in the tips of their digits to break away from the collagen that bonds them to a bony chip in the tip of the toe. The spur then pierces the flesh of the toe pad, resulting in instant claws.

These insta-claws are unique in the animal world to the Astylosternus genus of frogs. Unlike other claws, these spurs are pure bone, without the keratin sheath you've seen on cat and dog claws (and every other vertebrate claw). And those claws can do damage (hence the spears and machetes). The Harvard University researchers who brought the findings to light have only ever worked with dead specimens, so they don't know how the claws are retracted. Most likely, given the absence of a retractor muscle, the claws retract passively once the toes relax. And, given that they are amphibians, most likely the torn flesh and ruptured collagen regenerates, at least to some extent.

"Hey, horror frog, does that hurt?"
"Every time."

Here's what an adult looks like. As if the claws weren't enough, it's also hairy. A hairy frog. It looks like it has just donned a grass hula skirt and is off to terrorize a luau. But, of course, those aren't real hairs. They are hair-like strands of skin that males grow when tending to their brood. The researchers' best guess is that the extra surface area of the strands allow the male frog to take in more oxygen while being a daddy. Fine. All right, frog. You've redeemed yourself...a bit. I'll forgive you the skirt.

Thanks for the horror frog, Rachel.


Anonymous said...


Not ugly, just a total bad ass.

Alison said...

That frog looks like it's prowling toward a researcher, ready for revenge!

"Where..." slash "...are..." slash "...my BABIES??"

Victorya said...

Now I know where stan lee got the idea for Wolverine. Bad Ass indeed. Even has the sideburns.