Etmopterus brosei sp. nov.: a new lanternshark (Squaliformes: Etmopteridae) from the southeastern Atlantic and southwestern Indian oceans, with a revised key to the Etmopterus lucifer clade

A new species of lanternshark, Etmopterus brosei sp. nov. (Squaliformes: Etmopteridae), is described from the southeastern Atlantic and southwestern Indian oceans. The new species resembles other members of the Etmopterus lucifer Jordan & Snyder, 1902 clade in having linear rows of dermal denticles, and most closely resembles the conspecific E. sculptus Ebert, Compagno, & De Vries, 2011 from the southeastern Atlantic and southwestern Indian oceans. The new species is fairly common along the upper continental slopes off South Africa, Mozambique, and seamounts along the Madagascar Ridge, including Walters Shoal, in 480–1200 m depth. It can be distinguished from other members of the E. lucifer clade by a combination of characteristics, including the arrangement of flank and caudal markings, shape and size of flank marking, the arrangement of dermal denticles along the body, and the presence of dermal denticles on the dorsal fin bases. A revised key to the Etmopterus lucifer clade is provided.