New Data on the Rare Alepocephalid Fish Photostylus pycnopterus

Abstract

New data are given on the unique and infrequently reported mesopelagic alepocephalid fish Pholostylus pycnopterus. The second figure of the species and the first figure of its distribution are presented. The new information involves, principally, the superficial structure of the stalked luminous organs and paired intermandibular flaps, numbers of gill rakers on all arches, and dentition; teeth of the premaxillary, maxillary and mandible increase in number with size of fish. All captures (17), excepting possibly two, were made within distinctly warm-water regions, and about half were made over or very near rather steeply inclined topography, the remainder over abyssal plains. Also, all captures except one are from areas of rather high productivity.