NEW ADDITIONS TO THE ICHTHYOFAUNA OF THE ANTLERS FORMATION (APTIAN-ALBIAN) OF SOUTHEASTERN OKLAHOMA

The Antlers Formation of Oklahoma is a relatively well-sampled terrestrial deposit of Aptian-Albian age, consisting largely of sandstones and claystones deposited in fluvial, deltaic, and strand-plain environments. Studies on the Antlers Fauna have focused mostly on the dinosaurs, mammals and squamates. Surprisingly, however, fish make up the vast majority of the fossils from this locality (approximately 55% of the fauna), but yet are underrepresented in the literature. Here, we reexamined purported fish teeth, jaws, scales, and unassociated vertebrae from the OMNH micro-site locality, V706, of Atoka County in southeastern Oklahoma. Previous reports from this site have included at least two species of hybodontiform sharks, two species of pycnodonts, an amiid, and a possible lepisosteiform. Further investigation of this same material, we are able to add new occurrences of three teleost groups (Osteoglossomorpha, Elopomorpha, and Clupeomorpha). Additionally, we reclassify the previous report of Lepisosteidae to Amiiformes, consistent with the findings of others from the contemporaneous Trinity Group and Holly Creek Formation of Texas and Arkansas, respectively. Unsurprisingly, these new additions bring the Antlers Formation closer to the diversity known from the Trinity Group of Texas, the geographically closest and most completely described ichthyofauna from the Aptian-Albian of North America. Focusing on the Antlers Formation allows for a more complete and thorough understanding of the underrepresented members of this aquatic ecosystem, during an important transition for these paleocommunities in the late Early Cretaceous.