Aspidodera sogandaresi n. sp. (Heterakoidea: Aspidoderidae) from Dasypus novemcinctus Linnaeus, 1758 is herein described. This nematode occurs in armadillos from as far south as the canal zone of Panama, north through central Mexico, and into the southern United States. Previously identified as Aspidodera fasciata (Schneider, 1866), this new species has blunt projections on the lips and lateral expansions at the distal tips of the spicules, whereas A. fasciata has conspicuous digitiform projections on the lips, and a terminal round expansion at the tips of the spicules. Other species of the family present in North America include Aspidodera binansata Railliet and Henry, 1913; Aspidodera vazi Proença, 1937; and Lauroia trinidadensis Cameron, 1939.