New Mexico Geological Society Annual Spring Meeting — Abstracts

Early Permian vertebrates have long been known from the Abo, Cutler, and Sangre de Cristo Fonnations in New Mexico. We report here the discovery of Early Pennian vertebrate fossils in the Red Tanks Member ofthe Madera Fonnation, which immediately underlies the Abo Fonnation in the Lucero Uplift of Valencia County. These fossils are from three localities in greenish gray shale in the upper 3-4 m of the
Red Tanks Member in T6N, R3W. The fossiliferous strata probably represents estuarine to floodplain deposits. Fossils recovered so far have been mostly removed from eroded surface material, but screenwashing at one site has yielded numerous microvertebrate fossils. Taxa identified include: several limb bone fragments of pelycosaurian reptiles; fragments of a rib and femur of a diadectomorph reptile; numerous centra of an embolomerous amphibian; and a tooth of a hybodont shark. This assemblage includes temnospondyls and pelycosaurs also found at younger Abo/Cutler localities and well represents the pelycosaur-dominated North American Early Pennian tetrapod fauna.