Revision of genus Melamphaes (Melamphaidae). I. Multi-Raker species: M. lugubris, M. xestoachidus sp. nova, M. microps, M. manifestus sp. nova

Abstract

The taxonomic revision of mesopelagic fish species of Melamphaes genus (Melamphaidae family) was performed on a significant number of specimens. The first part of the paper includes the description of multi-raker species of Melamphaes genus that are characterized by 20 and more rakers on the first gill arch, by seven soft rays in the ventral fin, by the absence of temporal spine, by 16–17 rays in the pectoral fin, and by 12–13 abdominal vestebrae. M. lugubris inhabits the northern Pacific Ocean, in the subarctic and boreal climatic zones. Newly described species, M. xestoachidus, which is similar to M. lugubris, is found in the northwestern Pacific Ocean, eastwards of the Kurils Islands. The species M. microps combines several species. Currently, M. microps species is known by the holotype obtained in the southwestern Indian Ocean and the juvenile caught along the southwestern African coast. The description of new species M. manifestus is performed under six specimens sampled in the equatorial areas of the eastern Atlantic Ocean.