Some gastropods from the lower Wolfcampian (Basal Permian) Laborcita Formation, Sacramento Mountains, New Mexico
Barry S. Kues
Twenty of the most common and conspicuous gastropods from two intervals of the Laborcita Formation east of the towns of Tularosa and La Luz are briefly discussed and illustrated. Although the faunas of both intervals are dominated by gastropods, few of these earliest Permian snail taxa have been studied previously. Assemblages near La Luz are in gray to tan limestone and calcareous shale lithologies, and are dominated numerically by specimens of bellerophontids (especially Retispira), Goniasma, Stegocoelia (Taosia), Pseudozvgopleura (Pseudozygopleura)? and Soleniscus? In contrast, the dark gray shale and siltstone sequence at the Tularosa quarry yielded a fauna consisting mainly of Glabrocingulum (Glabrocingulum), G. (Ananias) and Amphiscapha. Several common species in both collections are undescribed, but are closely related to, and probably descended from, known Middle—Late Pennsylvanian taxa. The Laborcita gastropod faunas are most similar to those of the coeval Red Tanks Member, Madera Formation, in central New Mexico some 200 km northwest of the Laborcita localities. Many other (mostly small) species of gastropods have been collected from the Laborcita Formation in addition to those discussed here; studies of them are in progress.
- Kues, Barry S., 1991, Some gastropods from the lower Wolfcampian (Basal Permian) Laborcita Formation, Sacramento Mountains, New Mexico, in: Geology of the Sierra Blanca, Sacramento and Capitan Ranges, New Mexico, Barker, James M.; Kues, Barry S.; Austin, George S.; Lucas, Spencer, G., New Mexico Geological Society, Guidebook, 42nd Field Conference, pp. 221-230.