Bathytyphlops sewelli

Common Name

Sewell's Spiderfish

Year Described

Norman, 1939


Dorsal Fin: 11-13
Anal Fin: 14-17
Pelvic Fin: 8 (none modified)
Pectoral Fin: 12-14 (none modified)
Branchiostegal Rays: 14-16
Gill Rakers: 6-7 on epibranch, 1 on corner, then 11-13 on lower limb (first arch)
Lateral Line: 65-70
Vertebrae: 65-70

Body fairly elongate with a large mouth. Eye vestigial and buried in skin. Teeth minute and granular. Pectoral fin simple (without modified rays) and not reaching past dorsal fin origin. Ventral fins without modified or elongate rays. Anal fin origin well behind last dorsal ray. Lowermost caudal fin rays not modified or elongate. There is no sub-caudal notch. Adipose fin absent. Scales on body and head.


Body white with dark scale edges. Head black. Fins black.


Maximum size to 300mm SL.


Benthic on continental rise and abyssal plain from 2,980-4,186m.


So far known from the E. Gulf of Mexico, off Colombia, and 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.