Chromodoris ruzafai Photo courtesy of Terry Gosliner

Chromodoris ruzafai, Ortea, Bacallado and Valdes, 1992

At first look, specimens of Chromodoris ruzafai appear to be juveniles of the common West American species Chromodoris sphoni (Marcus, 1971). However, a careful examination will show that the color pattern is a little unusual. The rhinophores are not white with a red and black apex, but red with a white apex. Also, the gill is entirely white, with some pink in the edges, not white with the apex red and black as in C. sphoni. In addition, the yellow spots on the dorsum appear to be larger, and there is not the typical pale blue band around the mantle margin of C. sphoni. If one specimen is dissected, then we will become aware that this is actually a different species, having several anatomical differences with C. sphoni.

The color resemblance between both species is surprising, but this is not an exception among the chromodorid nudibranchs. Rudman was the first author introducing the concept of color groups (several species sharing a similar color pattern) in nudibranch systematics. In fact, he divided his review of the Indo-Pacific Chromodoridae into several papers, each of them dealing with a different color group, rather than different taxonomic groups. Rudman named each color group with the name of the most common of its species. Examples are the Chromodoris quadricolor, Chromodoris splendida, Noumea purpurea and Chromodoris epicuria color groups. In the Atlantic Ocean, several color groups have been recognized by Ortea: blue Hypselodoris, Chromodoris clenchi and Chromodoris luteorosea color groups. The origin and ecological implications of the color groups in nudibranchs are still poorly understood. Any color group has been already introduced to include C. sphoni and C. ruzafai. Another chromodorid with a similar coloration known from the West Pacific coast is Hypselodoris agassizii.

C. ruzafai is not a common species, and at present has only been collected from the Galapagos Islands. Therefore, provisionally has to be considered as endemic to these islands. Very little is known about the biology of C. ruzafai. Animals are usually collected in tide pools or deeper, but always in shallow waters. The spawn of one specimen was found in March. The eggs are very densely packed and they have an average diameter of about 123 µm. The feeding preferences of this species are unknown.

The specimens studied in the original description were collected during the two scientific expeditions of the Museo de Ciencias Naturales de Tenerife (Spain) to this archipelago, in Isabela and Santiago Islands. The species is named after Angel Prez Ruzafa, a Spanish marine biologist who assisted in the collection of the material.

I'm a 29 years old opisthobranch lover. I was born in a little shore village in the North-West coast of Spain, called Muros de Nalon, the type locality of a couple species of nudibranchs. Since I was a little boy, I used to go the beaches close to my house collecting all kind of animals and plants. My interest for opisthobranchs started the very first day I found a beautiful Hypselodoris cantabrica in a rocky area. That day I decided that these were the animals I wanted to work with. I was lucky to find that Jesus Ortea (Kankel to his friends) worked with the University of Oviedo, the closest University to my village. He taught me everything about the research on the taxonomy of these animals, and thanks to his entrepreneurship, I had the chance to participate in several scientific trips to the Caribbean and the Red Sea. During that time I got my Bachelor degree in Biology and later my Ph.D. in Zoology at the University of Oviedo under Kankel's supervision. I was also working for several months in the Museum National d'Histoire Naturelle in Paris, as an invited assistant curator, having as my first duty the curation of the opisthobranch collection. I had the luck to work with Philippe Bouchet and Serge Gofas from whom I leared many things about systematics, nomenclature, and the work in a natural history museum. Now I have a post doctoral fellowship of the Spanish government (SEUI) to work in the California Academy of Sciences with Terry Gosliner. Am thankful that I have the opportunity to learn phylogenetic systematics techniques as well many other things from Terry, and have access to probably the biggest collection of nudibranchs in the world. I've also the luck to meet and work with Dave Behrens. The research project for my fellowship is a review of the systematics of the cryptobranch dorids. The first results will be published soon by Terry and me, but the completion of the whole project will probably take two years more. Send Angel mail at avaldes@casmail.calacademy.org

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