PHENOTYPIC DIVERSITY OF PROCOLOPHONID DENTITION

Procolophonidae is an extinct clade of small-bodied parareptiles that originated in the late Permian and persisted through the Permo-Triassic mass extinction. Procolophonids continued to diversify throughout the Triassic before becoming completely extinct by the end of the Triassic. Small-bodied tetrapods are essential members of present-day and extinct ecosystems, but the ecological role of many small-bodied animals during the Triassic recovery, such as procolophonids, has yet to be systematically analyzed. As such, we lack a comprehensive understanding of post-extinction recovery and resource availability during the Triassic. Tooth morphology is a well-documented measure of function and diet and can be used to deduce ecological niche in extinct organisms. To evaluate the dietary scope of procolophonids, the dentition of thirty-five species were analyzed (n=35). To do this, we measured the last tooth of each tooth row and statistically compared them with modern reptiles that exhibit a variety of dietary specializations (n=101). Initial findings indicate that procolophonids exhibited a variety of diets, evidenced by differences in maxillary and dentary tooth dimensions. These measurements reveal four dental morphogroups: (1) small teeth with rounded bases, (2) buccolingually widened, ovoid teeth, (3) mesiodistally -widened teeth, and (4) large, molariform teeth. While many procolophonids possessed teeth with similar dimensions as extant reptiles, members of the family Leptopleuronini fall outside of known tooth dimensions. Preliminary data suggests temporal shifts in ecomorphological diversity over time.