Wyoming Fossil Finds Reveal Tiny Primate Tetonius varleyorum and New Primate-Evolution Clues

Paleontologists in southern Wyoming report Tetonius varleyorum, a new omomyid primate about the size of a mouse lemur from ~50 million years ago, based on jaw and tooth fragments found at Smiley Draw’s Tim’s Confession. The site also yielded Arapahovius gazini and Anemorhysis savage, making three omomyid species co-located at an early Eocene locality. Published in the Journal of Human Evolution, the findings expand the Tetonius story beyond the Bighorn Basin and suggest branching evolution (not a single, linear anagenetic path) in early primates, broadening the geographic and macroevolutionary context.