Transverse lines on Nembrotha lineolata

August 17, 2000
From: Dirk Hasberg

I found this species while diving off Townsville, Queensland, Australia [Flinders Reef, Coral Sea] earlier this year. I've tried to identify it but to no avail.
Thought it might be worth sending a photo in to you for identification. I'd never seen a nudibranch with markings perpendicular to the body before this one.

Dirk Hasberg

Hasberg, D., 2000 (Aug 17) Transverse lines on Nembrotha lineolata. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from

Dear Dirk,
I must say it's the first time I have seen one like this also. With the proviso that I would need to look at its anatomy to be 100% sure, my feeling is that this is a very strange colour form of Nembrotha lineolata. If so, it must have faced west instead of north when the stripes were being applied!

While it is amazing how scientists can now delve into the makeup of the human genome, we are still a long way from really knowing how genes translate into things like colour patterns. If you look at the photo I have posted alongside of a fairly typical N. lineolata you will see I have added arrows alongside zones where there are transverse bands of extra longitudinal brown lines. It is possible that some short-circuit in the message from the genes during development, or some mutation in the genes themselves has made the transverse band dominant in your animal.

It is indeed fascinating. All other features of the colour pattern match typical N. lineolata, although the yellow at the base of the rhinophores and gills in your animal is rather faint.

If you have any other interesting photos, they would be very welcome on the Forum.

Best wishes,
Bill Rudman.

Rudman, W.B., 2000 (Aug 17). Comment on Transverse lines on Nembrotha lineolata by Dirk Hasberg. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from

Related messages

  1. Nembrotha lineolata from sthn Queensland
    From: Gary Cobb, October 14, 2008
  2. Re: Nembrotha rutilans mating
    From: Tamara Hartwich, August 8, 2008
  3. Sex in East Timor
    From: Brian Francisco, April 28, 2008
  4. Re: Nembrotha lineolata - feeding observations
    From: Richard Swann, April 15, 2008
  5. Is this Nembrotha rutilans ?
    From: Aaron Fink, February 15, 2008
  6. Nembrotha lineolata - finding mating partners?
    From: Carlos R. Munda, July 13, 2007
  7. Mating pair of Nembrotha lineolata
    From: Carrie Lo, May 25, 2007
  8. Re: Nembrotha lineolata from Tanzania
    From: Wilhelm van Zyl, May 31, 2006
  9. Nembrotha lineolata from Tanzania
    From: Claus Gregersen, May 29, 2006
  10. Nembrotha lineolata - feeding observations
    From: Brian Francisco, March 28, 2006
  11. Nembrotha lineolata from Sulawesi
    From: Bob Whorton, February 15, 2006
  12. Nembrotha lineolata from west Malaysia
    From: Ho Wei Kwok Alvin, September 12, 2005
  13. Re: Nembrotha lineolata with transverse lines
    From: David Bush, August 2, 2005
  14. Nembrotha lineolata with transverse lines
    From: David R. Bush, June 15, 2005
  15. Nembrotha lineolata from Fiji
    From: David & Leanne Atkinson, June 14, 2003
  16. Nembrotha lineolata - reproduction
    From: Vasa P. Sirinupongs, June 10, 2003
  17. Nembrotha lineolata from Borneo
    From: Mark Burnett, January 27, 2003
  18. Nembrotha lineolata from North Sulawesi
    From: Alice Lee, January 21, 2003
  19. Nembrotha lineolata from nthn Sulawesi
    From: Helmut Schirmböck, July 9, 2002
  20. Nembrotha lineolata laying eggs
    From: Mary Jane Adams, May 22, 2002
  21. Nembrotha lineolata from the Solomons
    From: Bruce Potter, September 14, 2001
  22. Nembrotha lineolata with spawn
    From: Jim Anderson, July 5, 2001
  23. Nembrotha lineolata feeding
    From: Erwin Koehler, August 22, 2000
  24. Nembrotha lineolata from Papua New Guinea
    From: Mary Jane Adams, August 9, 2000
  25. Nembrotha lineolata from Philippines
    From: Erwin Koehler, January 17, 1999
  26. Nembrotha from SE Sulawesi
    From: Lindsay Warren, April 22, 1998
  27. Nembrotha at Port Stephens
    From: David & Leanne Atkinson, January 9, 1998

Show factsheet and all related messages