Aldrovandia phalacra

Common Name

Hawaiian Halosaur

Year Described

Vaillant, 1888


Dorsal Fin: 10-12
Anal Fin:
Pectoral Fin: 11-13
Pelvic Fin: I, 8
Lateral Line Scales: 24-28 (to anus)
Branchiostegal Rays:
Gill Rakers: 19-23 (total on first arch)
Pyloric Caeca: 5-8

Body very elongate and moderately compressed. Skin firm. Mouth relatively small. Palatine tooth patch separated from pterygoid by a distance less than half its length. Snout relatively short. 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. First dorsal ray is very short and vestigial. Dorsal fin origin posterior to pelvic fin origin.


Body light gray with a silvery-blue sheen on the sides. Vent white.


Maximum size to 50cm TL.


Benthopelagic from 500-2,300m. Over soft calcareous ooze.


Off the E. U.S. from New England to the Bahamas. Also off S. Brazil.


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.

Sulak, K. J. 1977. Aldrovandia oleosa, a new species of the Halosauridae, with observations on several other species of the family. Copeia 1977 (no. 1): 11-20.

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.