Well, I’d certainly be terrified. Not only does this amphibian have hair, but New Scientist reports, it also snaps its own bones to create claws – by pushing the fragments through its skin:
“Some other frogs have bony spines that project from their wrist, but in those species it appears that the bones grow through the skin rather than pierce it when needed for defence,” says [David] Blackburn [of Harvard University’s Museum of Comparative Zoology].
At rest, the claws of T. robustus, found on the hind feet only, are nestled inside a mass of connective tissue. A chunk of collagen forms a bond between the claw’s sharp point and a small piece of bone at the tip of the frog’s toe.
The other end of the claw is connected to a muscle. Blackburn and his colleagues believe that when the animal is attacked, it contracts this muscle, which pulls the claw downwards. The sharp point then breaks away from the bony tip and cuts through the toe pad, emerging on the underside.
The end result may look like a cat’s claw, but the breaking and cutting mechanism is very different and unique among vertebrates. Also unique is the fact that the claw is just bone and does not have an outer coating of keratin like other claws do.
Didn’t Wolverine do that for a while? Until the comic book editors decided that was just too disturbingly weird for comics??? The full article is far stranger, including cooking hints for spicy frog and wonderment over how – or if – these bone-spur claws are retracted.