Heron Island, intertidal [Great Barrier Reef, Australia], 7 mm long, January 1994. Photo: Julie Marshall
This species was very briefly described by Pruvot-Fol, from New Caledonia, as green with darker green spots, the edge of the parapodia bearing up to four pairs of dendritic papillae. Pruvot-Fol considered the parapodial papillae to be sufficiently distinct to erect a new genus . Carlson & Hoff (1978) report a similar, very small species (max. length 6.5mm), from Guam. The only difference is that their specimens had only 2 pairs of parapodial papillae. As Pruvot-Fol noted that the most anterior pair of papillae in her specimen were very small, it is most probable that the Guam specimens are conspecific. There is a good photo in Atsushi Ono's book (p47) from Kerama Ids.
• Pruvot-Fol, A. (1930). Diagnose provisoires (incomplètes) des espèces nouvelles et liste provisoire des mollusques nudibranches recueillis par Mme. A. Pruvot-Fol en nouvelle Calédonie (Ile des Pins). Bulletin Muséum National d'Histoire Naturelle Paris, series 2, 2(2): 229-232.
Rudman, W.B., 2001 (October 23) Elysia mercieri (Pruvot-Fol, 1930). [In] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/elysmerc
September 14, 2005
From: Clay Carlson & Patty Jo Hoff
Concernng message #14705:
Here are a couple of Elysia mercieri if you wish to use them. We have
recorded the beast from Guam, Rota, Tinian and Saipan in the Marianas; and in the other Micronesian areas of Palau, Pohnpei and The Marshalls.
Upper Photo: El 012_2 , 4mm; Guam, Bile Bay, reef flat; 25 October 1976.
Lower Photo: El 012_3. ~2.5mm; Guam, Bile Bay, boat channel; 18 May 1970
Clay & Patty Jo
firstname.lastname@example.orgCarlson, C. & Hoff, PJ, 2005 (Sep 14) Elysia mercieri from Guam. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/14746
Dear Clay & Patty Jo,
Thanks for these photos. I wonder if there is more than one of these papillate species. Your looks a bit different from the one I have seen in New Caledonia and Julie Marshall has photographed at Heron Island [message #6710]. I am not sure what to make of Elysiobranchus ryukyuensis Ichikawa, 1993, but it seems to be part of the same group. Perhaps it is one species in which the papillae are quite variable in development.
September 10, 2005
From: Oren Lederman
I posted the following pictures on our local forum but we couldn't identify it. Any idea what it is ?
It's the second time i find this kind of slug.
Locality: Divers Village, Eilat, Israel. Red Sea. Depth: ~5 meters. Length: ~3-4 mm. 24 Aug 2005. Photographer: Oren Lederman
email@example.comLederman, O., 2005 (Sep 10) Elysia mercieri? from the Red Sea. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/14705
I am not 100% sure because I can't see enough detail, but I think it is an elysiid. The only one I know with long papillae on a very long rhinophores is Elysia mercieri. However it doesn't have tufts of papillae at the parapodial edge, as that species does, so I am not sure. Perhaps Kathe JUensen will recognise it.
April 22, 2002
From: Julie Marshall
Attached are a couple of images of Elysia mercieri. Like the species of Carlson & Hoff this animal had only two sets of parapodial papillae. It was 7 mm in size and found at Heron Island [Great Barrier Reef] under a dead coral slab at the reef crest at low tide in January 1994. The other distinguishing feature of this species, apart from the parapodial papillae, is its very long, thin rhinophores which are ornamented with papillae.
Marshall, J., 2002 (Apr 22) Elysia mercieri from Heron Island. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/6710
I have also seen specimens which have pinkish markings as well. As we can see in the close-up of the head, the colour of the animal is dependent on plant pigments stored in fine branches of the gut found in the body wall.
October 29, 2001
From: Cory Pittman
During my recent trip to Christmas Island, Line Islands [Sept 2001], this little Elysia turned up in an algae wash from a shallow reef platform just off the beach in front of the Captain Cook Hotel. It was at less than 0.5 m. At 4.5 mm in length, I suspect it's a juvenile.
firstname.lastname@example.orgPittman, C., 2001 (Oct 29) Elysia sp. from the Line Islands. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/5555
I'm pretty sure this is Elysia mercieri which grows a little bit bigger than this and is usually more green than red. However I don't know of another species that has 3 tufts of gill-like papillae arranged along the parapodial edge like this.