A new Myliobatiformes (Chondrichthyes, Batoidea) from the Miocene of Río Negro Province, Argentina and a review of the fossil Myliobatiformes of Argentina

Abstract

We report a dental plate belonging to a Myliobatiformes (Chondrichthyes, Batoidea) from the Gran Bajo del Gualicho Formation (Saladar Member; Upper Early Miocene-Lower Middle Miocene) located in the Gran Bajo del Gualicho locality, Río Negro Province, Argentina. The new specimen represents the first record of an associated, partially articulated tooth plate of Myliobatiformes in Argentina, whose informative nature invites us to review the fossil record of the group. A detailed description and comparisons with taxa from different families and genera within the Myliobatiformes are presented together with a phylogenetic analysis that includes extant and fossil taxa. We propose a new genus that would include the specimen described here (MAPBAR-3671) and two Neogene taxa from North America and Europe (Myliobatis magister and Myliobatis crassus).