The Night Stalker, Manambulus perhorridus, is a large, ferocious, pack-hunting, flightless leaf-nosed bat from Batavia, from After Man: A Zoology of the Future by Dougal Dixon. Once other vertebrates had established themselves on the islands, a new family of ground-dwelling predatory bats arose. These creatures walk on their front legs (on what would, in the case of a flying bat, be its wings, the site of most of its locomotors muscles). Their hind legs and feet are still used for grasping, but now fall forward to hang down below their chin. As the bats locate their prey purely by echolocation, their ears and nose flaps have developed at the expense of their eyes, which are now atrophied.
Artwork from After Man By Dougal Dixon Used Without Permission