Augerinoichnus Helicoidalis, a new helical trace fossil from the nonmarine Permian of New Mexico

Abstract

New Mexico contains a significant record of trace fossil assemblages, in terms of both abundance and ichnodiversity, from Lower Permian nonmarine depositional settings. Most notable amongst these are the trace fossil assemblages in the Robledo Mountains Formation of the Robledo Mountains in Doña Ana County, southern New Mexico, as recognized by the recent proposal to designate this area as a national monument. These trace fossil assemblages formed on a tidal flat under largely non-marine conditions (Mack and James, 1986; Hunt et al., 1993; Lucas et al., 1995a, 1998) and are dominated by the trackways of tetrapods and arthropods, yielding important information on the paleoecology, diversity and behavior of late Paleozoic arthropods (Braddy and Briggs, 2002; Minter and Braddy, 2006a), as well as evidence of specialized foraging strategies (Minter et al., 2006). Additional Lower Permian trace fossil assemblages occur at a number of localities in New Mexico and represent a variety of nonmarine depositional settings.