Aldrovandia affinis

Common Name

Gilbert's Halosaur

Year Described

G√ľnther, 1877


Dorsal Fin: 11-13
Anal Fin:
Pectoral Fin: I, 11-14
Pelvic Fin: I, 8 (rarely 7 or 9)
Lateral Line Scales: 13-17 (to pelvic), 25-31 (to anus)
Branchiostegal Rays: 10-11
Gill Rakers: 13-15 (total on first arch)
Pyloric Caeca: 6-9

Body very elongate and moderately compressed. Mouth relatively small. Palatine tooth patch joined at midline. Snout long and pointed. Scales absent on top of head and opercle. Lateral line scales two times larger than the body scales. Lateral line scales continuous with each other. Scales above lateral line number 13-16. Scales around belly usually 7. First dorsal ray is very short and vestigial. Dorsal fin origin above or slightly anterior to pelvic fin origin.


Pale brown to almost white, with dark brown pigment on the opercle, lower head, basal anal fin, tail, and ventral midline. Lateral line canal unpigmented. Interior of mouth very dark. The pyloric caeca are black. Vent white.


Maximum size to 55cm TL.


Most common over the continental shelf from 700-2,200m. Benthopelagic over calcareous bottoms.


Scattered records from New England to Florida, the northern Gulf of Mexico, and off the Caribbean islands.


McDowell, S.B. In: Cohen, D.M., N.B. Marshall, A.W. Ebeling, D.E. Rosen, T. Iwamoto, P. Sonoda, S.B. McDowell, W.H. Weed III, and L.P. Woods. 1973. Fishes of the Western North Atlantic. Part 6. Hereromi, Cyprinodontoidei, Berycomorphi, Xenoberyces, Anacanthini. Memoir No. 1. Sears Foundation for Marine Research; Yale University, New Haven, CT. 698 pp., 235 plates.

Whitehead, P.J.P. , M.-L. Bauchot, J.-C. Hureau, J.G. Nielsen and E. Tortonese. 1986. Fishes of the North-eastern Atlantic and the Mediterranean. Vol. I-III. UNESCO. Fishes of the North-eastern Atlantic and the Mediterranean.