New Early Devonian pteraspidids (Agnatha, Heterostraci) from east-central Nevada

Three new species and genera of pteraspidids (Agnatha, Heterostraci), Tuberculaspis elyensis, Pirumaspis lancasteri, and Lamiaspis ¡ongiripa, are described from the Sevy Dolomite, east-central Nevada. They form part of a vertebrate fauna of typical Early Devonian aspect that indicates a correlation with previously described faunas from the Beartooth Butte and Water Canyon Formations of Utah and Wyoming, thus improving the known distribution and diversity of these faunas. Correlation with an accurately dated fauna in Death Valley, California, enables this fauna to be dated to the late Emsian (inversus-serotinus Zones).