Bathypterois phenax

Common Name

Blackfin Spiderfish

Year Described

Parr, 1928


Dorsal Fin: 14-15
Anal Fin: 9
Pelvic Fin: 9 (first two thickened and elongate)
Pectoral Fin: 2 tiny upper rays; then 2 elongate rays (joined for most of length); then 1 short and 3 tiny rays; then 7-9 long lower rays
Branchiostegal Rays: 12-13
Gill Rakers: 10-12, 1 on corner, then 27-28 on lower limb (first arch)
Lateral Line: 55-60
Vertebrae: 53-54

Body fairly elongate with a tiny eye and a large mouth. Teeth small. Pectoral fins complex, with several elongate upper and lower rays extending beyond anal fin. Ventral fins with first two rays thickened and elongate (less than SL). Anal fin origin above last ray of dorsal fin. Lowermost two caudal fin principle rays are elongate (less than SL). Sub-caudal notch present. Adipose fin present. Body scales small and simple.


Body gray to black with scale pockets outlined in white. Dorsal and caudal fins lighter, with dark blotches at their bases.


Maximum size to 180mm SL.


Continental slopes from 827-2,651m over soft bottoms. Props itself up over substrate on elongated pelvic and caudal fin rays.


New England to the Caribbean Sea, including the Gulf of Mexico. Also off SE Brazil.


Franco, M.A., A.C. Braga, G.W. Nunan, & P.A. Costa. 2009. Fishes of the family Ipnopidae (Teleostei: Aulopiformes) collected on the Brazilian continental slope between 11 degrees and 23 degrees S. J. Fish Biol. 75(4): 797-815.

McEachran, J.D. & J.D. Fechhelm. 1998. Fishes of the Gulf of Mexico. Volume 1: Myxiniformes to Gasterosteiformes. University of Texas Press, Austin. i-viii + 1-1112.