G is for Grangeria.
Grangeria is a large hoofed mammal closely related to horses that lived during the middle Eocene. Whether or not Grangeria is a valid name, or that members of Grangeria are better called Eomoropus is a topic of discussion in paleontology.
Nevertheless, Grangeria is a member of a group called chalicotheres, which were unusual hoofed mammals in that their front legs were proportionately very long, and they may have knuckle-walked like modern anteaters.