A frog with fur? And sharp, cat-like claws? Either might sound improbable, and Africa’s hairy frog Trichobatrachus robustus is certainly stranger than fiction.
Why is the hairy frog hairy?
This 11cm-long amphibian is hairy during the mating season, when the male develops a thick bristle-like fringe along his flanks and thighs. This is actually a mass of thin strands of skin replete with blood vessels, and is a temporary organ that may boost breathing ability in times of need – the male guards his mate’s eggs and may remain underwater for days without coming up for air.
And its claws?
But this frog has another clever survival trick. With the flex of a foot muscle, it can produce an arsenal of sharp, curved claws that snap out of its toes like switchblades. These thorn-shaped toe bones rapidly pivot when triggered, sending the pointed tip slicing through the frog’s skin and transforming its feet into formidable weapons. A few violent kicks can lacerate a foe and draw blood from an unsuspecting biologist. People in Cameroon, who hunt these frogs for food, use spears and machetes to avoid handling them.
The triggered claw bones eventually move back into place and the toe wounds heal over – until the next time the frog needs to pull out its blades.