Ceratosoma amoenum
(Cheeseman, 1886)

Order: NUDIBRANCHIA
Suborder: DORIDINA
Family: Chromodorididae

DISTRIBUTION

Temperate southern Australia and northern New Zealand.

PHOTO

UPPER RIGHT: Long Reef, Sydney, New South Wales, Oct 1986 (small orange and wine spots); Kurnell, Sydney, May 1987 (large orange spots). PHOTOS: Bill Rudman.
LOWER LEFT: Eden, southern New South Wales, Feb 1983. PHOTO: Bill Rudman.
LOWER RIGHT: Upper Photo - Port Phillip Bay, Victoria, Australia, March 1986. PHOTO: Bill Rudman. Lower Photo - Eagle Bay, Cape Naturaliste, southwestern Western Australia, sublittoral reef, April 1978. PHOTO: R. Kuiter.

Although in external shape this species looks much like a species of Hypselodoris its internal anatomy, especially the reproductive system and foregut anatomy show that its relationships lie with the genus Ceratosoma. Most species of Ceratosoma are characterised by a large recurved dorsal horn as in Ceratosoma alleni but it is absent in both the temperate water species in southern Australia, C. amoena and Ceratosoma brevicaudatum.

Ceratosoma amoenum also shows considerable colour variation through out its range. In Western Australia the orange spots are very small and numerous and the reddish purple spots form a submarginal band around the edge of the mantle. Moving east, the reddish purple spots become more numerous and widespread over the mantle and the orange spots become larger. In New Zealand the orange spots are very large and the purple markings are often absent.

Note added 4 July 2007: The name is changed today from C. amoena to C. amoenum - see message #20101.

  • Rudman, W.B. (1984) The Chromodorididae (Opisthobranchia: Mollusca) of the Indo-West Pacific: a review of the genera. Zoological Journal of the Linnean Society 81: 115-273.
  • Rudman, W.B. (1988) The Chromodorididae (Opisthobranchia: Mollusca) of the Indo-West Pacific: the genus Ceratosoma J.E. Gray. Zoological Journal of the Linnean Society 93(2): 133-185.

Authorship details
Rudman, W.B., 1998 (December 14) Ceratosoma amoenum (Cheeseman, 1886). [In] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/factsheet/ceraamoe

Related messages

  1. Ceratosoma amoenum from South Australia
    From: Agnieszka Malkowska, April 12, 2010
  2. Ceratosoma amoena 'doing things'
    From: Samuel Kemp, April 27, 2007
  3. Ceratosoma amoena - more photos
    From: Floor Anthoni, April 27, 2007
  4. Ceratosoma amoena - mating aggregation
    From: Floor Anthoni, April 26, 2007
  5. Ceratosoma amoena - feeding aggregation
    From: Dr J Floor Anthoni, April 26, 2007
  6. Ceratosoma amoena - feeding aggregation?
    From: Ross Armstrong, April 25, 2007
  7. Re: Hypselodoris bennetti & Ceratosoma amoena
    From: Lynda Clarke, April 11, 2007
  8. Re: Ceratosoma amoena from sthn Queensland
    From: Rachel Murphy, March 6, 2007
  9. Ceratosoma amoena from Bateman's Bay, New South Wales
    From: Eileen Baker, January 9, 2007
  10. Ceratosoma amoena from sthn Queensland
    From: Bruce Wilkie, July 15, 2006
  11. Ceratosoma amoena from Tasmania
    From: John Silberberg, July 6, 2005
  12. Ceratosoma amoena (?) laying eggs
    From: Martina Fuchsberger, April 11, 2005
  13. Ceratosoma amoena from South Australia
    From: Carl Mooney, January 26, 2005
  14. Ceratosoma amoena from New Zealand
    From: Pam McAssey, February 6, 2004
  15. Ceratosoma amoena
    From: Mathew McGuire, February 1, 2004
  16. Colour variation in Ceratosoma amoena
    From: Sean McMahon, January 21, 2004
  17. Ceratosoma amoena feeding
    From: David & Leanne Atkinson, December 24, 2003
  18. Ceratosoma amoena - feeding
    From: Sue Newson, July 12, 2003
  19. Ceratosoma amoena laying eggs
    From: Leanne & David Atkinson, June 13, 2003
  20. Ceratosoma amoena laying eggs
    From: Leanne & David Atkinson, March 11, 2003
  21. Ceratosoma amoena on food sponge
    From: Mark Burnett, February 23, 2003
  22. Ceratosoma amoena from New Zealand
    From: Mark Burnett, February 21, 2003
  23. Ceratosoma amoena from Lord Howe Island
    From: W.B. Rudman, January 8, 2003
  24. Ceratosoma amoena from Maroubra, Sydney
    From: Chris Partridge, December 8, 2002
  25. Ceratosoma amoena from Sydney, NSW
    From: Allan Saben , November 18, 2002
  26. Ceratosoma amoena from sthn New South Wales
    From: Tim McKenzie, July 10, 2002
  27. The food of Ceratosoma amoena
    From: Craig Worthington, January 3, 2002
  28. Ceratosoma amoena from NSW, Australia
    From: Stuart Hutchison, November 22, 2001
  29. Chromodoris splendida? from New Zealand
    From: Colin Gans, October 5, 2001
  30. Ceratosoma amoena - information needed
    From: Edward Terry, September 27, 2001
  31. Ceratosoma amoena - unusual shape & behaviour
    From: Des Paroz, January 10, 2001
  32. Re: Are these all Ceratosoma amoena?
    From: Des Paroz, August 12, 2000
  33. Are these all Ceratosoma amoena?
    From: Des Paroz, August 10, 2000
  34. Ceratosoma amoena mating
    From: Grey McNeil, July 12, 1999
  35. Ceratosoma amoena from New Zealand
    From: Ross Armstrong, December 14, 1998

Show factsheet and all related messages