There are three named species: Smilodectes gracilis, Smilodectes gingerichi and Smilodectes mcgrewi.[1]
Smilodectes gracilis
Smilodectes gracilis was an adapiformesprimate from the early Eocene, some 55 million years ago. S. gracilis was found on the land mass of North America and based on its dental morphology, S. gracilis was a folivore.[2]
S. gracilis had a dental formula of 2.1.4.32.1.4.3 and had a relatively short snout, with rounded frontal bone as compared to other nothactines.[2] This species lacked symphyseal fusion[3] and this species of primate had comparatively reduced olfactory bulbs and a more expanded visual cortex.[2] This suggests that S. gracilis was a diurnalspecies.[2]S. gracilis had a cranial capacity of 9.5 cc.[3] It is thought that S. gracilis had an average body mass of around 2.1 kilograms.[2] Based upon its postcranial skeleton, S. gracilis was a vertical clinger and leaper.[3]