Identifying and siding the stylohyoid bone for North American artiodactyls

Abstract

AbstractThe stylohyoid is the largest bone in the hyoid complex surrounding the throat in artiodactyls. There is little published information to allow its identification to species or anatomical side. Our study examined comparative stylohyoid bones to provide criteria for taxonomic identification, using 494 animals representing 13 artiodactyl species, including all species native to the continental United States. The goal was to find criteria showing at least 95% success in separating between species or species groups. Osteometric and discrete feature criteria were found to provide strong distinctions between some species through an iterative set of comparisons arranged in a dichotomous key. For example, a small artiodactyl bone could be identified as pronghorn (Antilocapra americana) with 100% success (n = 260) if it exhibited both an S‐shaped dorsal aspect and a ratio of angle width to anterior end width > 1.6. Consistent criteria could not be found for some other species, notably between small bovids and between the 2 species of deer (Odocoileus sp.). Our study also extracted stylohyoids in place to provide criteria for siding, using 28 carcasses representing 7 species, and found they can be readily sided based on a marked concavity on the lateral side.