Re: Acanthodoris rhodoceras from California

August 11, 2006
From: Ken-ichi Ueda

Concerning message #17213:

Those are some great pics. I too saw this species for the first time this summer, though I saw much larger specimens. When I put two in the same container, they started mating!

While they were mating, I noticed an odd behavior: each one would reach out with a rhinophore and touch its mate, then quickly recoil the rhinophore. Is this behavior common among mating dorids? This was the first time I'd ever seen mating nudibranchs, so I wasn't sure what to make of it. I also saw a different individual laying eggs in the same pool. I'm afraid my pics aren't nearly as nice as Kevin's, but I thought they might be interesting.

Locality: Fitzgerald Marine Reserve, Moss Beach, 0 m, California, USA, Pacific Ocean, 11 July 2006, Rocky intertidal. Length: 4-5 cm. Photographer: Ken-ichi Ueda.

Ken-ichi Ueda

kenichi.ueda@gmail.com

Ueda, K.M., 2006 (Aug 11) Re: Acanthodoris rhodoceras from California. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/17334

Dear Ken-ichi,

Your photos clearly showing the high degree of color variation in this species.

Concerning your question about rhinophores - interesting observation.  Acanthodorids have exceptionally long rhinophores for dorids.  I can't remember anyone noting the "touching the mate" behavior before, but lets think about it.  The rhinophores are the sensory organs of the critter, and if you wanted to check on identity of your mate, and position yourself for copulation, AND you cannot see, it would make sense to point them in the mates direction, insuring the greatest chemical signal.  This would be similar to aiming an antennae in the direction of a radio or TV stations broadcasting antennae.

We always welcome comments from others.

Best wishes,
Dave Behrens

Behrens, D.W., 2006 (Aug 11). Comment on Re: Acanthodoris rhodoceras from California by Ken-ichi Ueda. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/17334

Factsheet

Acanthodoris rhodoceras

Related messages

  1. Is this Acanthodoris brunnea?
    From: Steve Lonhart, July 11, 2007
  2. Acanthodoris species in California
    From: Kevin Lee, September 6, 2006
  3. Acanthodoris rhodoceras from California
    From: Kevin Lee, July 28, 2006
  4. Acanthodoris rhodoceras from California
    From: Denise Weisman, June 13, 2005
  5. Acanthodoris rhodoceras from California
    From: Marina Tidwell, October 16, 2003
  6. Acanthodoris rhodoceras from California
    From: Bill Rudman, March 4, 2003

Show factsheet and all related messages