Gyrinomimus bruuni

Common Name

Bruun's Whalefish

Year Described

Rofen, 1959


Dorsal Fin: 20
Anal Fin: 18
Pectoral Fin: 18
Lateral Line Pores: 19
Gill Arches: 4

Genus diagnosis after Paxton (1989) for females:

Dorsal fin base 17% SL. Head length 31.5% SL. Body rather elongated with a huge mouth (third of body length). Snout rounded. Head wider than body. Eye tiny. Nasal organ small. Jaws slightly convex to straight on upper but concave on lower. Four distinct gill arches. Gill tooth plates contiguous. Lateral line conspicuous with large round pores inside a channel with raised rim. Lateral pores get smaller rearward and the final two have small dermal flaps. No vertical rows of papillae on lateral line. Lateral line system continues onto head as a series of pores and sensory openings. Additional pores on lower jaw and snout. Jaw teeth relatively long (three times longer than wide) in irregular rows. Vomerine tooth patch rectangular or flat. Dorsal and anal fins located far back on body, with bases slightly elevated. Cavernous tissue located around the anus and anal fin base. None elsewhere on body Caudal fin with less than 17 principle rays. Pelvic fin absent. Pectoral fin small and inserted low on body. Body flabby and scaleless except for large, diagnostic scales associated with the lateral line canals. Four lappets of flesh around anal fin base.

Males and juveniles unknown.


Preserved material dark brown overall.


Atlantic specimen from Bear Seamount was 150mm SL.


Type material taken at bathypelagic depths (4820m). Atlantic material taken with a tow that got to 1400m depth.


In the W. Atlantic known only from the seamounts off the northeastern U.S.A. but likely more widespread. Also off Brazil.


Afonso, G. V. F., Di Dario, F., Eduardo, L. N., Lucena-Fr├ędou, F., Bertrand, A., & M.M. Mincarone. 2021. Taxonomy and distribution of deep-sea bigscales and whalefishes (Teleostei: Stephanoberycoidei) collected off northeastern Brazil, including seamounts and oceanic islands. Ichthyology & Herpetology, 109(2), 467-488.

Mincarone, M.M., F. Di Dario & P.A.S. Costa. 2014. Deep-sea bigscales, pricklefishes, gibberfishes and whalefishes (Teleostei: Stephanoberycoidei) off Brazil: new records, range extensions for the south-western Atlantic Ocean and remarks on the taxonomy of Poromitra. Journal of Fish Biology v. 85: 1546-1570.

Moore, J.A., K.E. Hartel, J.E. Craddock & J.K. Galbraith. 2003. An annotated list of deepwater fishes from off the New England region, with new area records. Northeastern Naturalist v. 10 (no. 2): 159-248.

Paxton, J.R. 1989. Synopsis of the whalefishes (family Cetomimidae) with descriptions of four new genera. Records of the Australian Museum v. 41: 135-206.

Rofen, R.R. 1959. The whale-fishes: families Cetomimidae, Barbourisiidae and Rondeletiidae. (Order Cetunculi). Galathea Report v. 1: 255-260, Plates 1-2.

Other Notes

The dorsal and anal fin counts of Cetomimus bruuni are higher than all other described species. Moore et al. (2003) state that W. Atlantic records belong to an undescribed species allied with C. bruuni.