Description of a new deep-sea Lantern Shark Etmopterus viator sp. nov. (Squaliformes: Etmopteridae) from the Southern Hemisphere
Lantern sharks (Etmopterus spp.) constitute a regular by-catch in longline fisheries conducted along the north-eastern Kerguelen Plateau shelf in depths of 600 to 1700 m. Kerguelen lantern sharks are morphologically close to E. granulosus, E. sp. B, South African E. cf. granulosus, and E. litvinovi. However, molecular phylogenetic analyses support the hypothesis that they represent a distinct cryptic species, which is in line with morphological characters separating the species from its Southern Hemisphere congeners. The new species is described as Etmopterus viator sp. nov. and differs significantly from E. granulosus, E. sp. B, and South African E. cf. granulosus in body shape characters as well as shape and density of dermal denticles. The poorly known E. litvinovi differs from Kerguelen specimens of E. viator sp. nov. by lacking flank and tail markings. Flank marking shape and molecular phylogenetic analyses of the new species support its assignation to the recently defined E. spinax clade. The species is widespread in the Southern Hemisphere.