Desmoinesian strata of the lower Bishop Cap Formation in Vinton Canyon, northern Franklin Mountains, west Texas, contain a rich gastropod fauna, in general resembling that of the upper Flechado Formation in north-central New Mexico. Distinctive elements of the Bishop Cap fauna include two new genera and five new species. Each species is represented by 30 or more specimens, sufficient to document ontogenetic change and intraspecific variability. The new taxa described here include the murchisonioid Altadema convexa new genus and species; the pseudozygopleurids Microptychis insolita new species, Trepsipleura chordanodosa new genus and species, and T. nodosa new species; and the orthonemid Hermosanema carinatum new species.

You do not have access to this content, please speak to your institutional administrator if you feel you should have access.