Pleurobranchus forskalii from South China Sea

May 9, 2003
From: Audrey Koh

Hi there!
We were doing a liveaboard weekend to the Udang Oil Rigs on White Manta ( and stopped to do an Exploratory Night Dive at Pulau Durai on our way back. It's the first time we have dived at this particular Island and we came across this huge sea slug. We were puzzled for a few days and did research to find out what it is. My day dive buddy, Maria, found a similar match on your web site. :-)

We were very excited about this finding and we hope that you could confirm what it is for us. My buddy, Peter, did more than 180 dives & I did more than 140 dives and this is the first time we saw it.

As I am an amateur photographer, the photos didn't come out well. It's really a bright burgundy red and it came out blackish red instead. :-( But I hope it will help start some documentation of findings in the South China Sea region. Here's more details:

Date/Time: 23 Apr 2003 20:05:48
Location: Pulau Durai, Anambas Islands, Indonesia, South China Sea- Found underneath a coral reef.
Colour: Bright Burgundy Red with White Patterns. Size: 25cm to 30cm. Water Temp: 29 - 30 Degree Celcius., Max Depth: 9 metres

I think it is Pleurobranchus forskalii?? Could you confirm please.
Audrey Koh

Koh, A., 2003 (May 9) Pleurobranchus forskalii from South China Sea. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from

Dear Audrey,
Yes this is the dark form of Pleurobranchus forskalii. It can grow to more than 30cm but is normally about half that size. Thanks for the information about yourself which I have added to the Participants List.
Best wishes,
Bill Rudman

Rudman, W.B., 2003 (May 9). Comment on Pleurobranchus forskalii from South China Sea by Audrey Koh. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from

Related messages

  1. Pleurobranchus forskalii from Singapore
    From: Ron Yeo, March 28, 2008
  2. Pleurobranchus forskalii from Indonesia
    From: Mirjam Broos, February 15, 2007
  3. Swimming Pleurobranchus
    From: Mark Schaer, June 20, 2006
  4. A pleurobranch from Saipan
    From: Takao Urasawa, August 19, 2005
  5. Re: Mystery slug from Malaysia
    From: Jimmy Goh, May 10, 2005
  6. Large pleurobranch from Malaysia
    From: Alphonsus Jude Joseph, April 28, 2005
  7. Is this a sea slug?
    From: Dominic Rutherford, February 2, 2005
  8. Pleurobranchus forskalii from Lizard Is
    From: Nils Anthes, January 10, 2004
  9. Pleurobranchus forskalii from Sabah
    From: Asther M. Lau, July 23, 2003
  10. Re: Mystery slug from Malaysia
    From: Michael Smith , March 27, 2003
  11. Mystery slug from Malaysia
    From: Michael Smith, March 26, 2003
  12. Pleurobranchus forskalii from Lord Howe Island
    From: W.B. Rudman, January 28, 2003
  13. Pleurobranchus forskalii from Solomons
    From: Bruce Potter, July 14, 2002
  14. Pleurobranchus forskalii from South Africa
    From: Valda Fraser, January 3, 2001
  15. Pleurobranchus synonyms in South Africa
    From: Ernest C.J. Seamark, June 17, 2000
  16. Spanish Dancer with white eggs?
    From: Jan Reyniers, April 6, 2000
  17. Re: Notaspidean defensive secretions
    From: Bill Rudman, May 14, 1999
  18. Pleurobranch acid secretions
    From: Rhanor Gillette, May 6, 1999
  19. Skin secretions in Pleurobranchus forskalii
    From: Clay Bryce, April 30, 1999
  20. Pleurobranchus forskalii, P. peroni
    From: K. Koyanagi, April 29, 1999
  21. Pleurobranchus forskalii in South Africa
    From: Ernest C.J. Seamark, April 17, 1999
  22. Opisthobranchs from Durban, South Africa
    From: Ernest Seamark, March 13, 1999

Show factsheet and all related messages