Chromodoris cf. geminus

Etang salé les bains, Reunion Island
Photo courtesy of Philibert Bidgrain

Chromodoris cf. geminus Rudman, 1987

This week Webmaster Mike has chosen an interesting species of uncertain identity. The Sea Slug Forum refers to specimens with similar coloration as possibly Chromodoris geminus . A look at the number of specimens photographed in the Indian Ocean, we see a good deal of variation in color, approaching that of C. geminus . The describer (Bill Rudman) himself is unsure. We will make no final identifications here.

Philibert’s specimen shown here from Reunion Island in the Indian Ocean, has the spots of C. geminus , but none of the normal coloration along the edge of the mantle. Having said that, the spots are also similar to those on Chromodoris kunei and Chromodoris tritos . Hummmm.

All of the specimens shown on the Forum, were photographed in South Africa or Mauritius. A large species, specimens can reach 8 cm.

Tell us what you think.

Dave Behrens
Gig Harbor, Washington
June 2006

Philibert searching sea slugs in “Moheli Island”,
a little island of Comoros (Mozambique channel, Indian Ocean)

As a biology teacher in Reunion Island (Reunion Island is situated in the Indian Ocean, approximately 750 km east of Madagascar.) for 14 years, I have been taking part in the activities of “Vie Océane”, an association dedicated to the information of as wide an audience as possible, and above all school children, about the “World of Corals”. Divers, photographs, teachers and Reunion Island University researchers are counted among its members.

Hence, “Vie Océane” participates in research work such as health coral reef monitoring, the inventory of the biodiversity and so on. For some time, I have taken over the works of Dr Maurice Jay (a specialist in molluscs presently working on microgasteropods) concerning sea slugs in Reunion and neighbouring islands (Mauritius Is , Comoros Is, ...). I’d welcome any information, document, photo of Reunion Island sea slugs so as to supplement our knowledge and data bank.

All species described in this Island are listed and discribed in my website. Reunion Island Sea Slugs website

The photo was taken with a Digital camera, C750 ultra zoom.(Olympus), in its Olympus housing. I don’t use flashlight, there is only about 10-20 cm deep, and it was summer light....

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Puerto Vallarta, Mexico
March 2005

Ali Hermosillo and Dave Behrens

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

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