Common Name
Abyssal Cusk-eel
Year Described
Roule, 1913
Identification
Dorsal Fin: 120
Anal Fin: 90
Pectoral Fin: 15-16
Caudal Fin: 8
Pelvic Fin: 2
Gill Rakers: 7-11 long rakers (lower limb of first arch)
Vertebrae: 18-21 precaudal
Body robust and elongate with a rounded snout. Snout relatively long. Eye very small (much shorter than snout). Opercular spine strong. Teeth villiform on jaws and palatine. Four basibranchial tooth patches: two median and a paired set between them. Paired set much smaller in size than posterior median patch and not overlapping. Dorsal origin over pectoral base. Anal fin origin well behind dorsal origin. Caudal fin elongate. Pectoral fins with rays free along almost half of length (last rays totally free). Pelvic fins long with 2 rays flattened distally and somewhat thicker in males. Cycloid scales cover entire head, body, and fins. Lateral line not distinct.
Color
Described as overall translucent pallid yellow-gray with darker gray pigment on the head, gill, and gut region. Inside mouth and throat blackish.
Size
Maximum size to ~300mm SL.
Habitat
One of the deepest known fishes: abyssal/hadal on the bottom between 5,180 and 7,160m.
Range
Known from the vicinity of the Mid-Atlantic Ridge but likely in other extremely deep areas of the Atlantic.
References
Anderson, M. E., & D. L. Stein. 2006. Redescription of the rare ophidioid fish, Holcomycteronus brucei, from two new specimens from the Southern Ocean. Polar Biology, 29, 640-642.
Nielsen, J.G., D. M. Cohen, D. F. Markle & C. R. Robins. 1999. Ophidiiform fishes of the world (Order Ophidiiformes). An annotated and illustrated catalogue of pearlfishes, cusk-eels, brotulas and other ophidiiform fishes known to date. FAO Fish. Synop. 125(18):178p.
Nielsen, J. G., N. D. King, & P. R. Moller. 2008. Rare abyssal, ophidiid fishes from off the Crozet Islands, Southern Ocean, with a new species of Apagesoma Carter, 1983. Cybium, 32(1), 43-50.
Other Notes
Best distinguished by it’s much lower pectoral fin ray count from other Holcomycteronus spp. A poorly known and rarely collected species due to its extreme habitat.