Discodoris rosi
Ortea, 1979

Order: NUDIBRANCHIA
Suborder: DORIDINA
Superfamily: EUDORIDOIDEA
Family: Dorididae

DISTRIBUTION

Atlantic coast of France, Atlantic and Mediterranean coast of Spain.

PHOTO

Upper: Belle-ile, Brittany, France, Atlantic Ocean. Site: Penhouet., Depth: 7m, Size: 15-20mm. August 16, 2002. Lower: two animals copulating. Belle-ile, Brittany, France, Atlantic Ocean. Site: La Cathedrale. Depth: 11m., Size: about 20mm, August 17, 2002. Photos: Marina Poddubetskaia

Ranges in colour from translucent orange or yellow to almost black, with a distinctive pattern of large white rings over mantle. The mantle is covered with small caryophyllidia [tubercles with radiating spicules].

Reference:
• Ortea, J.A. (1979) Deux nouveaux Doridiens (Mollusca, Nudibranchiata) de la cote nord d'Espagne. Bull. Mus. Natl. Hist. Nat. Paris, 4(1), Section A, Zoologie, Biologie et Ecologie Animales, 3: 575-584.

Authorship details
Rudman, W.B., 2002 (September 24) Discodoris rosi Ortea, 1979 . [In] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/discrosi

Related messages


Re: First record of Discodoris rosi from the UK

October 1, 2009
From: David Kipling

Concerning message #21943:

Dear Bill,

I believe we have a UK sighting of Discodoris rosi that pre-dates Mark Warren's 2008 record from the Isles of Scilly by some six years, and places this species on the UK mainland for the first time.

We spotted this specimen on 24 August 2002 on a reef outside of Penzance (~30 miles NE of the Isles of Scilly) that is adjacent to the wreck of the Mystique. This photo was taken in the very early days of our adventures in digital photography, using an Olympus C3000 in a PT-010 housing, so forgive the somewhat poor quality of the picture!

Although we noted it as something unusual in our log books we were not able to identify it at the time, and it has been languishing in our digital archive ever since. However, now having seen Mark and Anna's pictures it does look like a specimen of Discodoris rosi.

Locality: Penzance, not recorded, probably 15-20 m, Cornwall, UK, Atlantic, 24 August 2002, encrusted rocky reef. Length: not recorded (but can guess by size of adjacent jewel anemone). Photographer: dD.

David Kipling

kiplingd@cardiff.ac.uk

Kipling, D., 2009 (Oct 1) Re: First record of Discodoris rosi from the UK. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/22569

Dear David,

Nice to get another record. The 6 year time difference certainly suggests there is a permanent population established in the SW of the UK.

Best wishes,
Bill Rudman

Rudman, W.B., 2009 (Oct 1). Comment on Re: First record of Discodoris rosi from the UK by David Kipling. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/22569

Re: Discodoris rosi from French Mediterranean

April 2, 2009
From: M. Poddubetskaia Ossokine

Concerning messages #22302; #22174:

Dear Bill,

To complete Dominique Horst's and Sandrine Bielecki's messages, here are some more photos of Discodoris rosi from French Mediterranean. Like in previous messages, the rings are barely visible but still present.

Locality: "La Faille", Port-Leucate, 13 m, France, Mediterranean, 14 April 2006. Length: 16 mm. Photographer: Marina Poddubetskaia .

We also have this species in Arcachon Bay (French Atlantic), but with obvious white rings.

Best wishes,
Marina.
Nembro website

nembro@yahoo.fr

Poddubetskaia Ossokine, M., 2009 (Apr 2) Re: Discodoris rosi from French Mediterranean. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/22368

Thanks Marina,

A quick glance at your photos suggests they are probably a dendrodorid but a closer look clearly shows the white rings of Discodoris rosi. These animals again seem to be on the same sponge as in earlier messages.

Best wishes,
Bill Rudman

Rudman, W.B., 2009 (Apr 2). Comment on Re: Discodoris rosi from French Mediterranean by M. Poddubetskaia Ossokine. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/22368

Re: Discodoris rosi laying egg mass ribbon

March 10, 2009
From: Dominique Horst


Concerning message #22302:

Hi Bill,

I was lucky to find a Discodoris laying a ribbon of eggs.
I've seen it when on the picture after the dive....

Locality: Cagnes, 23m, France, Mediterranean sea, 08/03/2009, muddy. Length: 25mm. Photographer: Dominique Horst.

Kind regards,
Dom.

dominique.horst@wanadoo.fr

Horst, D., 2009 (Mar 10) Re: Discodoris rosi laying egg mass ribbon. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/22323

Thanks Dom,

I've also included a close-up showing the darker patches on the mantle which make me pretty convinced this is D. rosi - but I could be wrong.

Best wishes,
Bill Rudman

Rudman, W.B., 2009 (Mar 10). Comment on Re: Discodoris rosi laying egg mass ribbon by Dominique Horst. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/22323

Re: Discodoris rosi from the french Mediterranean

March 2, 2009
From: Dominique Horst

Concerning message #13989:

Hi Bill,

I suppose this is a colour variation of Discodoris rosi without the white rings around the darker patches. The base of the rhinophores are quite transparent.

The egg-mass was on the sponge where they usually feed, with no other slug, so I've supposed that it is their egg ribbon.

Locality: Cagnes, 23 m, France, Mediterranean sea, 28 February 2009. Length: 30 mm. Photographer: Dominique Horst.

Kind regards,
Dom.

dominique.horst@wanadoo.fr

Horst, D., 2009 (Mar 2) Re: Discodoris rosi from the french Mediterranean. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/22302

Dear Dom,

This animal certainly looks as though it could be Discodoris rosi. I have included a close-up which shows the dark patches. I agree that is missing is the white ring that normally outlines these dark patches.

Interestingly your animal seems to be the same as the one in Sandrine Bielecki's recent message [#22174] which I tentatively identifed as Carminodoris boucheti. Both here animal and yours seem to be on the same sponge, which in both cases seems to have tall cylindrical outgrowths. Perhaps this sponge is an encrusting sponge and the tall outgrowths are just tubes or branches of another animal or plant that the sponge has overgrown? If so, it could possibly be a Microciona, like the one identified by Bernard Picton in Mark Warren's message [#21943 ]. I would be grateful for any feedback from local experts.

Best wishes,
Bill Rudman

Rudman, W.B., 2009 (Mar 2). Comment on Re: Discodoris rosi from the french Mediterranean by Dominique Horst. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/22302

Baptodoris cinnabarina ? from French Mediterranean

February 13, 2009
From: Sandrine Bielecki

Concerning message #22163:

Hi Bill
Here is another specimen for which we need your contribution for identification, it has been suspected to be Baptodoris cinnabarina but I'm not convinced.

Locality: Antibes, 35 m, France, Mediterranee, December 2008. Length: 3 cm. Photographer: Gilles Cavignaux.

Thanks for help
Sandrine Bielecki

sandrine.b3@free.fr

bielecki, S., 2009 (Feb 13) Baptodoris cinnabarina ? from French Mediterranean. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/22174

Note added 2 March 2009: This is possibly Discodoris rosi. See message #22302.

Dear Sandrine,

I am not an expert on Mediterranean species but I think Baptodoris cinnabarina is supposed to have whitish rhinophores. Your animal has traces of a median ridge on the mantle and the rhinophore and gills pockets are bordered with a whitish pattern, so it could be Carminodoris boucheti.

Hopefully someone with knowledge of the Mediterranean fauna can help us identify your animal.

Best wishes,
Bill Rudman

Rudman, W.B., 2009 (Feb 13). Comment on Baptodoris cinnabarina ? from French Mediterranean by Sandrine Bielecki. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/22174

First record of Discodoris rosi from the UK

October 15, 2008
From: Mark Warren


Please find attached picture of critter spotted on Sea search week based on St Martins in the Isles of Scilly - UK last week. Despite having numerous books with us we were unable to determine a name for this little (well comparatively not that little) critter and were wondering if you could proffer a name?

Locality: 'Dry Ledge' St Marys, 20 metres approx, Isles of Scilly, United Kingdom, Atlantic, 9th October 2008, Weeded alcove in rock outcrop. Length: 25 mm. Upper two photos: Mark Warren. Lower photo: Anna Cawthray.

Mark Warren

mark.warren@fsmail.net

Warren, M., 2008 (Oct 15) First record of Discodoris rosi from the UK. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/21943

Dear Mark,

This is Discodoris rosi. It has never been recorded north of the French Coast before, so this is quite exciting. It is a fairly large and conspicuous nudibranch so I suspect that we are seeing a true range extension here. Sally Sharrock, who was leading your trip, sent me another picture of the same species taken by Anna Cawthray, so there seems to be a population there, not just a chance individual.

The Scilly Isles are probably one of the places we can expect species crossing the English Channel to be seen first, if global warming continues to affect the North Atlantic by warming it. It was first described from Galicia, NW Spain as recently as 1979, indeed I saw it there myself in 1978. At the time I identified the sponge it was feeding on as Microciona strepsitoxa, a red encrusting sponge on which it is reasonably well camouflaged. I suspect that is the sponge in Anna's picture. Since then it has been reported from a few scattered sites throughout the Mediterranean Sea and here on the Forum as far north as Belle-Ile in Southern Brittany. The sponge seems to have a more northerly distribution in Britain and Ireland, so perhaps that made it possible for the nudibranch larvae to get started once they had somehow crossed the English Channel.

Best wishes,
Bernard Picton

Picton, B.E., 2008 (Oct 15). Comment on First record of Discodoris rosi from the UK by Mark Warren. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/21943

Discodoris rosi from Slovenia

June 13, 2005
From: Tom Turk

Dear Bill,
I am sending you few photos of nudibranchs from the Slovenian coast. I have tentatively identified the species, but I need some additional help. Most of them were taken in shallow infralitoral zone. I think this is Discodoris rosi.

Locality:  Piran, Slovenia, Adriatic Sea. Spring 2005. muddy, phytal. Photographer: Tihomir Makovec

Cheers,
Tom Turk

tom.turk@bf.uni-lj.si

Turk, T., 2005 (Jun 13) Discodoris rosi from Slovenia. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/13989

Dear Tom,
I loook  forward to some confirmation from local experts but I think your identification is probably correct. Although extremely obscure, the mantle does seem to be covered in the whitish rings characteristic of that species.
Best wishes,
Bill Rudman

Rudman, W.B., 2005 (Jun 13). Comment on Discodoris rosi from Slovenia by Tom Turk. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/13989

Re: Discodoris rosi from nthn Spain

March 1, 2004
From: Alma Sanchez

Dear Dr. Rudman,
Regarding the geographical distribution of Discodoris rosi Ortea, 1979, [#12318] this species has been recorded in the Spanish Mediterranean coast (catalonian, Granada, Málaga) and Strait of Gibraltar also.

• García-Gómez, J. C. 1983. Moluscos opistobranquios del Estrecho de Gibraltar y la bahía de Algeciras. Iberus, (3): 41-46
• Luque, A. 1986. Contribución al conocimiento de los moluscos gasterópodos de las costas de Málaga y Granada. Editorial de la Universidad Complutense de Madrid.
• Sánchez-Tocino, L., Ocaña A. and García, F. J. 2000. Contribución al conocimiento de los moluscos opistobranquios de la costa de Granada (sureste de la Península Ibérica). Iberus, 18 (1): 1-14.

Best wishes
Alma

almasanchez83@hotmail.com

Sanchez, A., 2004 (Mar 1) Re: Discodoris rosi from nthn Spain. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/12326

Thaks Alma
Bill Rudman

Discodoris rosi from nthn Spain

February 27, 2004
From: Ricardo Roberto Fernández

Dear Bill,
Some years ago I collected and photographed these orange dorids, but I haven't been able of identifying them yet. Could you help? If you can't, I would be grateful too if you included the photograph in the unidentified category. The dorids were collected on the Northern Coast of Spain, in Asturias. I don't remember the depth, but it was diving.

Thank you very much in advance and congratulations for your great website.

Ricardo Roberto Fernández

rirober@telecable.es

Fernández, R.R., 2004 (Feb 27) Discodoris rosi from nthn Spain. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/12318

Dear Roberto,
This is Discodoris rosi, which is apparently only known from the Atlantic coast of Spain, and France.
Best wishes
Bill Rudman

Rudman, W.B., 2004 (Feb 27). Comment on Discodoris rosi from nthn Spain by Ricardo Roberto Fernández. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/12318

Discodoris rosi from French Brittany

September 27, 2002
From: Marina Poddubetskaia


Dear Bill,
Here are some photos of Discodoris rosi Ortea, 1979 from the Atlantic Ocean.

Upper: Belle-ile, Brittany, France, Atlantic Ocean. Site: Penhouet., Depth: 7m, Size: 15-20mm. August 16, 2002
Lower: two animals copulating. Belle-ile, Brittany, France, Atlantic Ocean. Site: La Cathedrale. Depth: 11m., Size: about 20mm, August 17, 2002

Best wishes,
Marina.

nembro@nembro.info

Poddubetskaia, M., 2002 (Sep 27) Discodoris rosi from French Brittany. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/7812

Thanks Marina,
This is a new one for the Forum.
Best wishes,
Bill Rudman.