July 4, 2006
From: Aidan Hampson
I just got a great shot of a pair of Mexichromis porterae breeding and thought you might like a copy for the Sea Slug Forum.
Locality: Isthmus Reef, Santa Cantalina Island, 20 ft, CA USA, Pacific, 24 June 2006, rocky Kelp forest. Length: 30 mm. Photographer: Aidan Hampson. [Motor MarineIII with Macro, F16, Fuji Provia100 film]
firstname.lastname@example.orgHampson A.J., 2006 (Jul 4) Photo of Mexichromis porterae. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/17045
Thanks very much for thinking of us. These animals have their reproductive organs on the right side of the body just behind the rhinophores, so from the way your two animals are aligned I suspect they are not actually mating. But I suspect their position is either pre- or postnuptial.
Another interesting thing in your photo is the bluish grey patch below the two nudibranchs. McDonald & Nybakken (1978) reported that this species feeds on the sponge Dysidea amblia, and this patch could well be a dysideid. I am sure one of out west coast colleagues can correct me if I am wrong. Some dysideids are often partially covered by sand grains or have them incorporated in their outer layers, which can make it very difficult to know if a chromodorid is feeding on a sponge or just crawling over a patch of sand. My guess is that these two animals are together because of the food sponge. That is not to say they won't mate - but to be totally unromantic, the initial attraction is the food, rather than the beauty of the nudibranchs.
McDonald, G.R. & Nybakken, J.W. 1978. Additional notes on the food of some California nudibranchs with a summary of known food habits of California species. The Veliger, 21(1): 110-118.
Mexichromis porterae from Laguna Beach, California
From: Kevin Lee, August 2, 2006
More on Mexichromis porterae
From: Clinton Bauder, July 29, 2005
Mexichromis porterae from California
From: Chris Grossman, July 28, 2005
Photos of Mexichromis porterae
From: Amber Thweatt, July 26, 2005
Mexichromis porterae mating
From: Chris Grossman , August 4, 2004
From: Lacey Keen, December 8, 1999
Another Mexichromis porterae query
From: beth, November 9, 1999
Information on Mexichromis porterae
From: Lacey Keen, November 4, 1999
Mexichromis from California
From: Scott Johnson, January 22, 1999