Aldisa pikokai

Aldisa pikokai Bertsch & Johnson, 1982
Family Aldisidae

This tiny orange-red nudibranch resembles a small encrusting sponge, the three pits on its back mimicking excurrent pores. The gills are white. Active only at night, it remains hidden under stones or in crevices during the day, most often between 6 and 30 ft. and sometimes as deep as 80 ft.

The species name comes from two Hawaiian words: piko ("navel") and kai ("sea"). The three pits reminded the zoologists who described this animal of pits pounded into pahoehoe lava in ancient times, into which children's umbilical cords were deposited. A rare and much larger nudibranch of the genus Sclerodoris closely resembles this species but has only one pit. A small orange-red lamellariid with a smooth rather than pitted surface also resembles it. To about 1/2 in.

Known only from the Hawaiian Islands.
Photo: Makua, O`ahu. 20 ft.

Photos and 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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