New Mexico Geological Society Annual Spring Meeting — Abstracts

Amphisauropus, a tetrapod footprint ichnogenus that is widely distributed in the Lower Permian of Europe, has previously been recorded in the United States only from Abo Pass in central New Mexico. New Mexico Museum of Natural History locality 5075 in the Cerros de Amado of central New Mexico contains a second occurrence of tracks that are readily assigned to Amphisauropus latus Haubold. These tracks are attributed to a seymouriamorph trackmaker. They are found in a 5-m thick crossbedded and ripple-laminated sandstone about 94 m above the base of the Wolfcampian Abo Formation, which is near the middle of an approximately 190-m-thick Abo section locally. At present, no associated ichnotaxa have been recovered from this unit. The Amphisauropus tracks are well preserved, and occur in a laterally confined area of several meters width that represents a levee or channel margin. There are no extensive trampled surfaces at locality 5075, as seen in the Amphisauropus occurrence at Abo Pass.

In Europe, Amphisauropus tracks are found in alluvial plain and lake margin facies of the Lower Permian red beds in Germany, France, the Czech Republic, Poland and Italy. In New Mexico, Amphisauropus is not found in Wolfcampian tracksites from the southern or northern parts of the state, which were formed on a coastal plain and in an upland environment, respectively. The distribution of Amphisauropus in New Mexico thus appears to be restricted to the central part of the state, which is interpreted as an inland alluvial floodplain.