Aeolidiella alderi from UK

August 8, 2005
From: Judith Oakley

Please can you help with identification of this sea slug. Could it be Aeolidiella sanguinea?

Locality: Dartmouth Marina, Devon, UK. Length: 7 mm. 29 June 2005. marina pontoon. Photographer: Judith Oakley

Judith Oakley

Oakley, J.A., 2005 (Aug 8) Aeolidiella alderi from UK. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from

Dear Judith,
Some of these species are difficult to tell apart but when you see a specimen in which the first row of cerata are so distinctly white like this, you can be pretty sure it is Aeolidiella alderi. In this species the cnidosac is much larger in the anterior row and since it fills at least the upper half of each ceras, its translucent white colour gives the anterior cerata their white appearance. In the posterior rows, where the digestive gland duct fills much of the cerata, the ceratal colour is produced by the colour of the digestive gland instead. Best wishes,
Bill Rudman

Rudman, W.B., 2005 (Aug 8). Comment on Aeolidiella alderi from UK by Judith Oakley. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from


Aeolidiella alderi

Related messages

  1. Aeolidiella alderi from Thau, French Mediterranean
    From: Dominique Horst, November 28, 2007
  2. Aeolidiella alderi from Croatia
    From: Mat Vestjens, July 13, 2006
  3. Aeolidiella alderi from Bembridge, UK
    From: Rebecca Cooksley, September 29, 2005
  4. Aeolidiella alderi from sthn England
    From: Judith Oakley, May 13, 2005
  5. Guernsey opisthobranch
    From: Richard Lord, November 20, 2003
  6. Aeolidiella alderi - defensive behaviour
    From: Marina Poddubetskaia, August 25, 2003
  7. Aeolidiella alderi + eggs
    From: Marina Poddubetskaia, August 10, 2003
  8. Aeolidiella alderi from Tunisia
    From: Anis, April 22, 2003
  9. Aeolidiella alderi or A. glauca
    From: Mauro Doneddu, January 21, 2003
  10. Aeolidiella alderi from Strait of Gibraltar
    From: Alma Sánchez, January 29, 2002
  11. Re: Cuthona granosa ? from the Mediterranean
    From: Bernard Picton , January 9, 2002
  12. Cuthona granosa ? from the Mediterranean
    From: Jean-Pierre Bielecki, December 19, 2001
  13. Aeolidiella alderi
    From: Jean-Pierre Bielecki, March 17, 2001
  14. Aeolidiella alderi and parasite
    From: Jean-Pierre Bielecki, February 20, 2001
  15. Aeolidiella alderi or A. glauca
    From: Bernard Picton , February 20, 2001

Show factsheet and all related messages