Taxonomy and biostratigraphy of the early Tertiary Taeniodonta (Mammalia: Eutheria): Summary

Abstract

The Taeniodonta is an order of archaic mammals known exclusively from the lower Tertiary of western North America (Schoch and Lucas, 1981a). Their remains are found in Puerean (lower Paleocene) to Uintan (upper Eocene) strata of the Rocky Mountain intermontane sedimentary basins (Figs. 13, 14; Table 12). In the San Juan basin of New Mexico and Colorado, the Puerean to Wasatchian (lower Eocene) sedimentary sequence includes the type localities for the Puerean, Torrejonian (middle Paleocene), and Tiffanian (late Paleocene) land mammal “ages” (Wood and others, 1941) as well as a classic Wasatchian fauna (Lucas and others, 1981). Thus, the San Juan basin mammalian faunas provide a sequence of faunas which can provide the basis for interbasinal correlation. The Taeniodonta are an important element of these faunas; many of: the type specimens and important referred specimens of these animals come from the San Juan basin. However, except for Patterson9s (1949b) brief review, a comprehensive study of this order has not been published for more than 80 years (Wortman, 1897b). Before a group of animals can be used, biostratigraphic correlation, its species- and genus-level taxonomy, and its known stratigraphic occurrences must be well established. In this paper, I revise the species-level taxonomy of the Taeniodonta and document their geographic and temporal (stratigraphic) distribution and I discuss their usefulness and implications for biostratigraphic correlation in western North America. SCope And Methods In this paper, I undertake a complete taxonomic revision at the genus- and species-level of the Taeniodonta based on the majority of the known specimens. The suprageneric classification and phylogeny of the taeniodonts is not considered here. Taxonomic judgments are made solely on the basis of morphology; extrinsic stratigraphic and geographic data, although recorded and considered important, are not used to define taxa.