A marine invertebrate fauan from the upper part of the Panther Seep Formation (earliest Wolfcampian) near Hembrillo Pass, San Andres Mountains, south-central New Mexico
— Barry S. Kues

marine invertebrate assemblage consisting of about 35 species is described from the upper 30-45 m of the Panther Seep Formation near Hembrillo Pass, in the central San Andres Mountains. The assemblage is dominated by brachiopods, which constitute >90% of the specimens, with far fewer sponge, coral, bryozoan, bivalve, gastropod, trilobite, crinoid and echinoid specimens. Of the brachiopods, four species—Neochonetes granulifer (24%), Pontisia kingi (23%), Composita subtilita (19%), and Renculatia n. sp. (15%)— comprise about 800/0 of about 1100 specimens collected. Stratigraphic position, the presence of several characteristic lower Wolfcampian species, including the gastropod Omphalotrochus, and known and inferred relationships to regional fusulinid zones all indicate an earliest Wolfcampian (earliest Permian) age for this assemblage relative to the recently revised Pennsylvanian-Permian boundary in the Midcontinent region. This assemblage appears to be slightly younger than faunas of the Bursum and coeval units in central New Mexico, but is slightly older than faunas of the overlying lower Hueco Group in this area. The occurrence of Omphalotrochus in this assemblage correlates well with the first appearance of the genus in the Midcontinent region, at the very beginning of the Wolfcampian Stage. The organisms of this assemblage lived in a shallow, offshore, open-shelf, normal-marine environment with relatively little water agitation.