Onychonycteris finneyi

Onychonycteris was the more primitive of the three oldest bats known from complete skeletons, having lived in the area that is current day Wyoming during the Eocene period, 52.5 million years ago.

==Taxonomy== Two specimens of Onychonycteris were found in the Green River Formation in 2003, and placed in a new family when the discovery was published in Nature, in February 2008. Onychonycteris means "clawed bat", in reference to the fact that this animal had claws on all five of its digits, whereas modern bats only have claws on the thumb (in most species) or thumb and index finger (in pteropodids). The specific epithet is a tribute to the fossil prospector and preparator who discovered it, Bonnie Finney.