Chirotherium, also known as Cheirotherium (‘hand-beast’), is a Triassic trace fossil consisting of five-fingered (pentadactyle) footprints and whole tracks.

These look, by coincidence, remarkably like the hands of apes and bears, with the outermost toe having evolved to extend out to the side like a thumb, although probably only functioning to provide a firmer grip in mud.

Chirotherium tracks were first found in 1834 in Lower Triassic sandstone (Buntsandstein) in Thuringia, Germany, dating from about 243 million years ago (mya).

They were found before dinosaurs were known and initial models of the trackmaker proposed that it was a bear or ape, which walked with its feet crossed.

The print's resemblance to mammals was only superficial; in reality, an external (lateral) ‘thumb’ was commonplace among Triassic archosaurs.