How many species of the gastropod genus Leucosyrinx (Conoidea: Pseudomelatomidae) are truly living in Southwestern Atlantic deep-waters?

Abstract

A revision of the species cited in the genus Leucosyrinx from Argentine waters is conducted. Leucosyrinx argentina sp. nov. is described after material collected off Argentina in: the Mar del Plata Submarine Canyon (528?2212 m depth), at 39°53.381´S, 55°52.197´W off Buenos Aires province (772 m depth), and in the Burdwood Bank (approximately 54°S in 187 and 642 m depth). Radulae, penis, operculum, ornamentation and ultrastructure of the shell are described. In addition, partial sequences of the mitochondrial cytochrome c oxidase subunit I gene (COI) are provided. After a review of the species previously described in the genus Leucosyrinx from Argentine waters, we concluded that L. argentina sp. nov. is the only living species truly recognized as belonging in this genus from the Southwestern Atlantic. This is the first study of the genus Leucosyrinx from this region that revises both morphological and molecular characters.