Trackway of a giant Arthropleura from the Upper Pennsylvanian of El Cobre Canyon, New Mexico

We document a giant terrestrial arthropod trackway assigned to Diplichnites cuithensis Briggs, Rolfe and Brannan, 1979 from the nonmarine redbeds of the Cutler Group (Late Pennsylvanian, Missourian?) in El Cobre Canyon, New Mexico, a classic Pennsylvanian-Permian vertebrate fossil locality. The El Cobre trackway is the first occurrence of D. cuithensis in the American Southwest, and, with a width of 38 cm, the largest known trackway of D. cuithensis. The tracks are attributable to Arthropleura, a gigantic terrestrial myriapod-like arthropod. The Late Pennsylvanian age and paleoenvironmental setting of the El Cobre trackway is consistent with most other records of D. cuithensis.