Doridomorpha gardineri

Photo courtesy of Atsushi Ono
Kerama Islands, Okinawa, Japan

Doridomorpha gardineri Eliot, 1906

Well here is a pleasant surprise. Until its inclusion in Atsushi Ono’s new book Opisthobranchs of Ryukyu Islands , page 233 (bottom), this cryptic little arminid nudibranch has not been reported in the popular literature or on any web site until now. One can certainly understand why. This tiny Arminina, only 9mm in length, is almost invisible on the blue coenothecalian coral, Heliopora coerulae.

This species has dorid-like rhinophores, set back on the notum, like Corambe , but unlike members of its sister genera, Armina and Dermatobranchus ,but the gill is typically arminacean, found under the mantle. It is the dorid shape and placement of the rhinophores that Eliot created this genus, the name (Doridomorpha) meaning - "morphologically (shaped) like a dorid."

The white patches on the mantle resemble pores on the corals surface. Documented sightings are few for this species, but include Fiji, Australia and Japan.

Thanks Atsushi for bringing this rare critter to the public eye.

Dave Behrens
Danville, Calif
Aug., 2004

Webmaster, Atsushi Ono, and Jerry Allen
May 2002, Photo courtesy of Akiko Miyamoto

Atsushi Ono is the owner of a dive service on Zamami Island in the Keramas off Okinawa that caters mainly to Japanese Divers. Atsushi evidently relocated from a small town north of Tokyo some fifteen years ago to Zamami Island. He subseqeuntly started a diving service. In fact, the economy of Zamami Island seems to based entirely on diving! For those of you who don't speak Japanese that is not a problem communicating with Atusushi, his written english is very good! Atsushi has a passion that so many of us also share and that is the observation and study of sea slugs. Atsushi published a field guide "Opisthobranchs of Kerama Islands " a couple of years ago that excels in the macro photography of small Japanese slugs. The most recent book is even better. His books are a must for any of those considering travel to that area of the world. We spent many an evening with Atsushi back in 2002 sharing pictures and experiences with branches. His enthusiasm is very intense, one can feel it in both talking and diving with him! Atsushi has been a regular contributor to the Okinawa Slug Site maintained by Bob Bolland.

I feel so strongly about the Ono-san's dedication to the study of Opisthobranchs that he is going to receive my unqualified recommendation for anyone planning a branching trip to Okinawa. His operation is first class and can be totally focused on branching if you bring enough people.

You can drop Atsushi a note at

Taxonomic information courtesy of:

David W. Behrens

Author: Pacific Coast Nudibranchs
Co-Author Coral Reef Animals of the Indo Pacific
Proprietor of Sea Challengers Natural History Books

Send Dave mail at

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