The genus Platytyphlops (Cumacea: Crustacea): A new species from Argentina, taxonomic status of Platytyphlops orbicularis (Calman, 1905), and remarks on the genus

Abstract

Platytyphlops uteae n. sp. is described based on a few specimens collected off the coast of Buenos Aires Province at 1011–1712 m depth during the surveys Atlantis II 60 (1971) and Talud Continental III (2013). In addition, Platytyphlops orbicularis, a species described by W. T. Calman in 1905 based on a single fragmentary specimen from West Ireland, is briefly redescribed. Furthermore, the specimens from the east coast of USA assigned to P. orbicularis by Calman in 1912, are herein considered to be conspecific with P. uteae n. sp. These two species are closely related. P. uteae n. sp. can be easily separated from P. orbicularis by: (1) the absence of submedian carinae on the carapace (present in P. orbicularis), (2) the female carapace being as wide as long (wider than long in P. orbicularis); and (3) the fifth pereopod as long as the fifth pereonite (much shorter than the fifth pereonite in P. orbicularis). Platytyphlops is a diverse genus that currently encompasses 24 species. Based on morphological data, three species groups within this genus are herein proposed. In addition, the bathymetrical range of all the species currently in Platytyphlops are updated and compared.