The genus Neophron contains only a single species. A few prehistoric species from the Neogene period in North America placed in the genus Neophrontops (the name meaning "looks like Neophron") are believed to have been very similar to these vultures in lifestyle, but the genetic relationships are unclear.[2][3] The genus Neophron is considered to represent the oldest branch within the evolutionary tree of vultures.[4] Along with its nearest evolutionary relative, the lammergeier (Gypaetus barbatus), they are sometimes placed in a separate subfamily, the Gypaetinae.[