Onychonycteris known species, hence "Onychonycteris" meaning "clawed bat". The specific epithet is a tribute to the fossil prospector and preparator who discovered it, Bonnie Finney. "Onychonycteris finneyi" was the strongest evidence so far in the debate on whether bats developed echolocation before or after they evolved the ability to fly. "O. finneyi" had well-developed wings, and could clearly fly, but lacked the enlarged cochlea of all extant echolocating bats, closer resembling the old world fruit bats which do not echolocate. This indicates that early bats could fly before they could echolocate. However, an independent evaluation of the "Onychonycteris" reference fossil in
Virginia big-eared bat make sounds that then echo off of objects around them, enabling them to find their prey while flying in the dark. Typically they prey on insects like moths, beetles, termites, mosquitoes and flies. Without echolocation, the bats would not be able to locate food. When analyzed, 97% of Virginia big-eared bat fecal pellets showed that the bat had consumed and digested Lepidoptera. Lepidoptera is a classification of insects that contains butterflies and moths. In Kentucky a similar study was done, examining the fecal pellets and stomach contents of the bats in and around the caves. The processed food showed that