Re: Eubranchus linensis from Portugal

Thanks Lucas,
I don't know enough about either species to have an opinion on whether E. linensis is a good species or not. I read the comparison with E. farrani and note they both fall into a group of species with a penial style and differentiated prostate gland, but wonder whether the other anatomical differences are significant. For example Edmunds & Kress's description of the reproductive system is based on reconstruction of serial sections, which make comparing relative lengths of ducts difficult, and from my experience with serial sections it is almost impossible to determine unequivocally that a duct inserts into the ampulla terminally or laterally, but near the tip.

Today's photo from Marco Faasse [#20727] of an animal that looks like E. linensis from Holland, and Jim Anderson's photo [#11240] from Scotland are certainly thought provoking.

I see in an early message [#1344] on the Forum that Bernard Picton notes that he could not distinguish differences in the colour morphs of E. farrani using protein electrophoresis. Techniques have advanced so quickly in this field of research that another look using molecular techniques would seem a necessary next step - when time and money allow of course.

• Edmunds, M. & Kress, A. (1969) On the European species of Eubranchus (Mollusca Opisthobranchia). Journal of the Marine Biological Association of the United Kingdom, 49: 879-912.

Best wishes,
Bill Rudman