The bats of 52.5 million years ago flew differently than the bats of today, and had a vastly different appearance. Onychonycteris had claws on all five of its fingers, whereas modern bats have - at most - claws for only two digits on each hand. It also had longer hind legs, and shorter forearms, similar to those of climbing mammals that hang under branches. This palm-sized animal had broad, short wings, which suggests that it could not fly as fast or as far as later bat species. Instead of flapping its wings continuously while flying, Onychonycteris would likely have alternated flapping and gliding while airborne.