New frog crabs (Brachyura, Raninoidea) from the early Maastrichtian of Paredon (Coahuila, NE Mexico)

We report several raninoid specimens collected from the lower Maastrichtian Lower Siltstone Member of the Potrerillos Formation (Difunta Group), NE Mexico. These specimens were collected from fine-grained sandstones that crop out at the NE edge of the Parras Basin, Coahuila. This outcrop is very close to a structural feature that has been active since Late Jurassic times (San Marcos Fault) and has affected depositional lithostratigraphic units from the Upper Jurassic to Upper Cretaceous. The studied specimens are assigned to Bournelyreidus paredonensis n. sp. (Lyreididae Guinot, 1993) and Coahuilanina difuntaensis n. gen., n. sp. (Raninidae de haan, 1839). A new subfamily, Coahuilanininae is described to accommodate the new genus and species, Coahuilanina difuntaensis. The new frog crabs represent the first formally described raninoids from the lower Maastrichtian portion of Difunta Group, adding to an already diverse assemblage of raninoids from Mexico.