This pin was originally released in March 2025, as a part of the Bizarre Beasts Pin Club.

Greening’s frog and Bruno’s casque-headed frog are tree frogs that live in eastern Brazil. Greening’s frog lives mainly in semi-arid habitats, while Bruno’s casque-headed frog mostly lives in dry shrublands, but can also be found in rainforests.
And the two species both have flat, bony heads, which they use for a defensive behavior called phragmosis – backing themselves into a shelter, like the middle of a bromeliad, and then blocking the top off with their heads. They’re also venomous. They both have skin that secretes a toxin more lethal than some snake bites, which gives them a powerful means of self defense.