New Mexico Geological Society Annual Spring Meeting — Abstracts

A partial skeleton of a large tyrannosaurid (NMMNH P-27469) from the Upper Cretaceous (upper Campanian) Hunter Wash Member, Kirtland Formation represents only the third relatively complete tyrannosaurid to be collected from New Mexico. Previously reported partial skeletons of tyrannosaurids from Upper Cretaceous strata of New Mexico include OMNH 10131, a skull and skeleton referred to Aublysodon cf. A.mirandus from the Fruitland or lower Kirtland Formation, and NMMNH P-25049, a partial skeleton of an immature tyrannosaurid from the Farmington Member, Kirtland Formation that has been referred to Albertosaurus but probably represents a new species of Daspletosaurus. Th new specimen is tentatively identified as an Albertosaurus based on the relatively uninflated ectopterygoid. A more precise and certain identification must await further preparation of the specimen.

NMMNH P-27469 is estimated to be from 40% -60% complete. It is largely or completely disarticulated and includes portions of the skull including portions of both dentaries, a maxilla, and an ectopterygoid, and postcranial elements including numerous vertebrae and ribs, a partial femur, and most of the left pelvic girdle. It also shows evidence of pathologies including a possible puncture wound of a palatal bone (ectopterygoid) with related infection of the bone and nearby periosteal tissue and a rib that shows a rib that shows a healed fracture.

The new tyrannosaurid specimen was collected from the Bisti/De-na-zin Wilderness Area under an excavation permit issued by the Bureau of Land Management (BLM) - the first permit of its kind to be issued on any federally-designated Wilderness Area.