The hairy frog Trichobatrachus robustus breaks its own bones to make weapons when cornered in a dangerous situation.

The frog Arichobatrachus robustus has a secret weapon on its hind legs. (Image: Wikimedia)
The claws go straight through the toes, making T. robustus frogs very dangerous. That’s why Cameron hunters had to use spears and pikes to kill frogs for their meat and avoid getting hit, according to ZME Science.

Male T. robustus, also known as “terror frogs” or “werewolf frogs,” have hair-like structures on their bodies and thighs during mating season. But those aren’t hairs, they’re actually superficial mesoderm with lots of blood vessels that act like fish gills. This structure helps the frog absorb more oxygen through its skin while nursing.

Ɲhung Ƭ Most notable feature. The robustus are the claws on the hind legs, hidden within a mass of connective tissue. Their claws are made entirely of bone and are attached to a muscle at one end. When a frog is attacked, it contracts its muscles, pushing its claws down. The sharp tips of the claws detach from the connective bones and emerge through the soles of the feet. According to Ɗavid Wake, a zoologist at the University of California, Berkeley, this appears to be the only method of self-defense in the animal kingdom.

The researchers never saw the frog T. robustus retract its claws. The frog doesn’t have the muscles to pull the claws into the skin, they think this frog’s claws can’t be retracted but can’t be sure.

Despite its terrifying appearance, the frog T. robustus is facing extinction. Cameroon’s rainforests are rapidly disappearing due to deforestation, farming and mining, threatening their habitat. Additionally, they were threatened with smuggling and were hunted by the Bakosi for the manufacture of infertility treatments. The researchers are working with conservation groups to raise awareness of the importance of rainforest conservation and are calling for greater regulation to prevent illegal frog trade and harvesting permits.