New Mexico Geological Society Annual Spring Meeting — Abstracts

The Peterson quarry, west of Albuquerque in central New Mexico, is a sauropod-dominated, fluvially-concentrated bonebed in the Brushy Basin Member of the Upper Jurassic Morrison Formation. We document a recently prepared incomplete plastron and carapace of a turtle from the Peterson quarry, which is the first non-dinosaurian vertebrate fossil from the quarry, and New Mexico’s first Jurassic turtle. The specimen consists of parts of the entoplastron, mesoplastron, hypoplastron, 6 peripherals and very damaged costals. It is readily assigned to Glyptops plicatulus (Cope) based on the following features: carapace low, surface ornamentation consists of tubercles and raised ridges, peripherals not scalloped, mesoplastra meet at midline, and plastron relatively thin. The identifiable suture pattern also well matches that of G. plicatulus. Glypyops is a characteristic Morrison Formation turtle previously reported from Wyoming, Utah and Colorado. The Peterson quarry record of Glyptops thus is its southernmost occurrence. We interpret Glyptops as a semi-aquatic omnivore that was a regular inhabitant of Morrison streams and stream margins.