Four new species of dragonfish genus Eustomias (Stomiiformes: Stomiidae: Melanostomiinae) from the western tropical Atlantic, with remarks on Eustomias minimus Clarke, 1999

Abstract

Abstract Four new species of the scaleless black dragonfish genus Eustomias are described based on specimens collected during the ABRACOS (Acoustics along the BRAzilian COaSt) expeditions along the Fernando de Noronha Ridge, off northeastern Brazil, western tropical Atlantic. Eustomias (Haploclonus) antea sp. nov. differs from its congeners by having a long chin barbel without appendages, ending in a very small terminal bulb without terminal filaments. Eustomias (Haploclonus) lucenae sp. nov. has the lowest count of photophores in the lateral series (56) and a simple, short barbel, ending in a small and asymmetrical terminal bulb. Eustomias (Nominostomias) ophioglossa sp. nov. differs from its congeners by the long chin barbel with two terminal bulbs and long terminal filament with bifurcated axis along its length and with bulblets of different sizes and arrangements inside. Eustomias (Nominostomias) bertrandi sp. nov. can be distinguished by the long chin barbel with two terminal bulbs, the distal bulb more than twice as long as the proximal one, and a short terminal filament. Morphological description of a specimen identified as Eustomias (Dinematochirus) cf. minimus is provided, and an overview of the species of Eustomias reported in Brazilian waters is presented and discussed.