Chromodoris baumanni

Photos courtesy of Ali Hermosillo
Puerto Vallarta, Mexico

Chromodoris baumanni Bertsch, 1970

This beautiful chromodorid was described by old brancher buddy Hans Bertsch, who named the species after a mentor of his - Father Anthony Baumann. It is a moderately uncommon species, but one found throughout the central Gulf of California south to the Galapagos Archipeligo. The specimens shown above, and that taken by webmaster Michael was collected at Punta Mita, near Puerto Vallarta, Mexico, in January of 1995.

Chromodoris baumanni is quite variable in color as noted by the examples shown on the Sea Slug Forum . In general, the species can be described as being translucent creamy yellow to opaque white. The mantle is covered with red spots , and the edge of the notum is encircled with a continuous band of orange to yellow spots. The foot has a marginal band of these same orange spots. Rhinophores white, with a red tip. Sometimes the notum has a dark red basal color to it, as seen here in Michael's photo, and in Ali Hermosillo's specimens on the Forum . Another good example is this specimen from the Galapagos.

Because of the variation in the notum color, some of our colleagues believe that this variation is a distinct new undescribed species. Branch officiando Terrence Gosliner says "absolutely not - It's Chromodoris baumanni based upon radular morphology and characteristics of the reproductive system." Thanks Terry - I would hate to see another species split, unnecessarily.

Anyway you cut it - this one is a beauty.


Bertsch, H. (1978). The Chromodoridinae nudibranchs from the Pacific Coast of America - Part II. The genus Chromodoris. The Veliger 20 (4): 307-327.

Dave Behrens
Danville, Calif
Jan . 2003

Image of Ali Hermosillo and Roberto Chavez Arce
Picture courtesy of Roberto Chavez Arce
Webmasters Notes: I want to thank Ali and Roberto for once contributing pictures and collecting data of an animal that has to say the least been perplexing since first oberserved by the Webmaster in Jan. 1995. Consulting with a local brancher at that time who specializes in the Pan American region, the animal was thought to be the "last undescribed Chromodoris of the Pan American Zone ." It was also sometimes referred to by others as the "green racing stipe" version of Chromodoris baumanni . In the process of putting this BOW together a poll was taken of branchers in a position to comment on this quandary. The vote was split right down the middle! Terry's work would seem to lay this issue to rest, or does it??

Michael D. Miller
San Diego, CA
Jan. 2003

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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