Cyerce sp.

Photo courtesy of Rie Nakano
Kermama Islands, Okinawa
May. 2002

Cyerce sp. (possibly undescribed)

In recent months we have learned about a number of new species common to the waters of southern Japan, but not observed previously, or elsewhere. The flood of new species seems directly proportional to the dramatic increase in the number of Japanese sea slug enthusiasts. This is apparent, as Webmaster Miller has described in a previous BOW , the emergence of dive operations like that of Atsushi Ono's which can upon request cater exclusively to divers seeking to see nudibranchs.

Among the many new species emerging from the tropical waters of Japan are several sacoglossids. This Cyerce may be a new species, but our current understanding of this genus makes it difficult to be sure. Rie's specimen here looks almost identical to Cyerce sp. 1 (page 39) in Ono's Opishtobranchs of the Kerama Islands as well as Cyerce sp. 3 on Bill Rudman's Sea Slug Forum. The specimens seem to differ slightly in the opacity of the cerata, but otherwise all have the same coloration with small black specks and a pink region near the tip of the cerata.

Like other sacoglossids this species has rolled rhinophores and is herbivorous, feeding on algae. The genus Cyerce does not seem to be one of the solar powered groups, who incorporate zoozanthellae into their tissue for the purpose of up taking the byproducts of photosynthesis.

Thanks Rie for sharing this one. It's a beauty.

Dave Behrens
Danville, Calif
Aug., 2002

Rie Nikano at Kerama Islands, Okinawa, May 2002

Since 1989, Rie has been a free lance writer and editor for Japanese diving magazines. Her main focus is interviews resulting in feature articles on nudibranchs for the Japanese diving magazine "Monthly Diver".

Rie was already interested in nudibrachs in 1987 when she first began diving. In 1996, She started the Japanese divers' site as webmaster. About this time Atsushi Ono from Okinawa also joined the site. Atsushi and Rie have been remained in close contact since first meeting in 1989.

To quote Rie:

"...Atsushi showed me how to photograph the many beautiful nudibranchs of the Kermama Islands. After many interesting discussions with Atsushi regarding Kerama's sea slugs, I became even more interested in nudibranchs! So, Atsushi is the real teacher of nudibranchs for me! In 1999, Atsushi recommended me to be the editor for his book " Opisthobranchs of Kerama Islands " . Thanks to Dr.Rudman, Dr.Bolland, and Mike Miller's site, I strived to do the best job for Asthushi and many readers..."

Rie has her own nudibranch web site (Japanese only).

Rie can be contacted at

Webmaster's Notes: Well, its doesn't get much better having as your first nudibranch photo instructor, Atsushi Ono!! We all should be as lucky!! Rie is a very talented underwater photographer although you'll never hear it from her. As with the other Japanese photographers on our May Okinawa trip, Rie excels in extreme macro photography using a digital setup! Myself and Jerry Allen are still on an upward learning curve in this area. Rie was the person who made our Okinawa trip work, without her assistance it ( the trip) never would have happened. We are entirely in her debt!-WEBMASTER.

Taxonomic information courtesy of:

David W. Behrens

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

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