Catopsalis (Mammalia: Multituberculata) from the Paleocene of New Mexico and Utah: Taxonomy and biochronological significance

Abstract

Recently collected specimens of Catopsalis fissidens from the Torrejonian interval of the Nacimiento Formation in the San Juan Basin, New Mexico significantly augment knowledge of the morphology and dental variability of the species. This new knowledge suggests C. foliatus Cope, 1882 (=C. johnstoni Fox, 1989) is a valid Puercan species and that C. fissidens Cope, 1884a is a subjective senior synonym of C. utahensis Gazin, 1939. This latter synonymy further increases taxa shared between the Dragon Canyon local fauna of Utah and the Torrejonian fauna of the San Juan Basin, thus supporting previous inclusion of the Dragonian land-mammal “age” in the Torrejonian.