Species diversity of the deep‐water gulper sharks ( S qualiformes: C entrophoridae: C entrophorus ) in N orth A tlantic waters – current status and taxonomic issues

The gulper sharks (genus C entrophorus ) are a group of deep‐water benthopelagic sharks with a worldwide distribution. The alpha taxonomy of the group has historically been problematic and the number of species included in the genus has varied considerably over the years and is still under debate. Gulper sharks are routinely caught in mid‐ and deep‐water fisheries worldwide and some have shown a considerable decline in abundance in the last few decades. Clear and consistent species discrimination of C entrophorus is essential for an efficient and sustainable management of these fisheries resources. Our study used molecular cytochrome oxidase subunit I (COI) and 16S ribosomal RNA gene sequences and morphometric data to re‐evaluate the diversity of C entrophorus in N orth A tlantic waters, including the G ulf of M exico, the C aribbean, and the M editerranean Seas. Molecular data separated N orth A tlantic C entrophorus into five well‐supported groups whereas morphometric data separated these same five groups and suggested three additional groups for which no molecular data were available. Four of the five groups identified in the N orth A tlantic also occur in the I ndian and/or P acific O ceans, thus extending the reported range of some species considerably. A species identification key for N orth A tlantic C entrophorus is provided based on our findings.  © 2014 The Linnean Society of London