Eggs to identify

February 21, 2000
From: Valda Fraser

Dear Bill
I noticed these eggs and decided to take a photo. Hopefully you'll know which kind of nudibranch laid them. How long does it take them to hatch?
Locality: South Coast KwaZulu-Natal SOUTH AFRICA, Scottburgh - 25m. 23 Jan 2000.

Valda Fraser

Dear Valda,
I'm afraid it is very difficult to identify nudibranchs from their egg masses. Firstly we know the egg masses of very few species, and secondly, quite a few have an egg ribbon very similar to your photo except for the colour. Some species, like in the genus Rostanga, have egg masses which are so distinctive that they can be used to identify the species, but that is very rare.

So if you ever see an animal laying an egg ribbon it is well worthwhile photographing it and the slug.

Have a look in the Gneral Topics Index for some other information on eggs and use the Search button as well because I have chatted about egg shape, development times etc on a number of occasions.

Best wishes,
Bill Rudman.

Rudman, W.B., 2000 (Feb 21). Comment on Eggs to identify by Valda Fraser. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from

Related messages

  1. Huge egg mass - Doris montereyensis ?
    From: Jackie Hildering, August 14, 2007
  2. Pleurobranchus forskalii eggs?
    From: Brian James, May 3, 2005
  3. Pink tiny nudibranch and concentric rings
    From: Francesca Riolo, March 25, 2005
  4. Galapagos egg ribbon
    From: Julianne Parolisi, January 2, 2005
  5. Nudibranch eggs on a fish
    From: Chris Grossman, August 4, 2004
  6. Unknown egg mass from Turkey
    From: Erwin Koehler , October 8, 2002
  7. Nudibranch Egg masses
    From: Laurette Hanekom, July 19, 2002
  8. Eggs
    From: Alice Lee, July 18, 2002
  9. Platydoris formosa? - egg ribbon
    From: Todd Garthwaite, June 27, 2002
  10. Do Sea Slugs lay eggs?
    From: Emily, March 13, 2002
  11. A strange place to lay eggs
    From: Mary Jane Adams , January 25, 2002
  12. Baki's Egg coils
    From: Bernard Picton, November 6, 2001
  13. Whose eggs are these?
    From: Baki Yokes, November 2, 2001
  14. Are these eggs?
    From: Beniamino Usai, October 23, 2001
  15. number of eggs
    From: Jeanette McInnes, October 7, 2001
  16. Opisthobranch egg masses
    From: Phanor Montoya, October 7, 2000
  17. How many eggs do sea slugs lay?
    From: MIKE, October 4, 2000

Show factsheet and all related messages