Family Hydatinidae

Hydatina physis Lamarck, 1801
Family Hydatinidae

Hydatina physis (Linnaeus, 1758) Family Hydatinidae Closely set black spiral lines mark the shell of this opisthobranch, which is pinkish, with faintly iridescent blue borders. Fleshy flaps (parapodia) over the back partially cover the shell (true of all bubble shells). It occurs on shallow reef flats, most often from January to May, and is seen at night when it feeds on bristle worms of the family Cirratulidae. The white egg mass is sometimes carried for a time on the side of the shell, which in large specimens may be 1 1/2 in. long. The species occurs in all warm seas. Photo: Waikiki, O`ahu. 2 ft.

Text courtesy of John Hoover

John P. Hoover lives in Honolulu. He has published two books on marine life of the Hawaiian Islands. His third (pictured at left), a field guide to the marine invertebrates of the Hawaii, will be available approximately May 1999. With over 600 photographs, it will cover 500 species, including 66 of Hawaii's most colorful and interesting opisthobranchs.

Hawaii's Fishes, a Guide for Snorkelers, Divers and Aquarists Mutual Publishing, 1993

Hawaii's Underwater Paradise, Mutual Publishing, 1997

Hawaii's Sea Creatures, a guide to Hawaii's Marine Invertebrates. Mutual Publishing, 1999.

John's books are available through Sea Challengers !

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