Hymenocephalus billsam

Family	Scientific Name	Author	Year	Common Name
Macrouridae	Hymenocephalus billsam	Marshall and Iwamoto	1973	Bigeye Grenadier

All Hymenocephalus Species: Anus not surrounded by a broad margin of naked black skin, located immediately anterior to anal fin (separated by 1 or 2 rows of scales at most). Branchiostegal rays 7. Head covering membranous, mostly naked and lacking spinulated scales. Pelvic-fin rays 10-14. Small lens-like structures on chest and in front of anus. Spinous second ray of dorsal fin smooth. Striations on gular membrane.

Hymenocephalus billsam

Unique Characteristics: Barbel absent or rudimentary, less than 10% of head length. Pelvic-fin rays 13 or 14 (rarely 12).

Similar Species:

Glasshead Grenadier, Hymenocephalus italicus

Glasshead Grenadier Hymenocephalus italicus. Barbel on chin about 10-15% of head length. Pelvic-fin rays 10 or 11 (rarely 12).

Reference

FAO 1990. (Cohen, D.M., Inada, T., Iwamoto, T., and N. Scialabba. 1990. FAO species catalogue. Vol. 10. Gadiform fishes of the world. (Order Gadiformes). An annotated and illustrated catalogue of cods, hakes, grenadiers, and other gadiform fishes known to date. FAO Fisheries Synopsis No. 125, Volume 10. 442 pp.