Stiliger fuscovittatus
Lance, 1962

Order: SACOGLOSSA
Superfamily: LIMAPONTIOIDEA
Family: Limapontiidae

DISTRIBUTION

West coast of Nth America from Ketchikan, Alaska to Gulf of California, Mexico, in both marine and estuarine conditions.  [Reported as invader in Texas & Florida].

PHOTO

Dana Landing, San Diego, California, April 1961. Photo: Jim Lance.

Aeolid-like in shape, the anterior surface of this sacoglossan is covered with cerata.  The rhinophores are simple. The body is white to dirty-white with reddish brown spots.  It is fairly transparent so the colour of its food in its digestive system shows through the body wall making it well camouflaged on its algal hosts There is a reddish-brown streak down the posterior face of each rhinophore which continues backwards on the body (hence its name) running posteriorly from the rhinophores.   Specimens reach 15 mm in length.

This species feeds on filamentous red algae, such as such as Polysiphonia and Callithamnion, (but not the Microcladia used in this photo as a background).

  • Behrens, D.W. & A. Hermosillo.  2005.  Eastern Pacific Nudibranchs - A guide to the opisthobranchs from Alaska to Central America. Sea Challengers. 137 pp. [note: photo #66 not S. fuscovittatus]
  • Lance, J. 1962.  A new Stiliger and a new Corambella (Mollusca: Opisthobranchia) from the northwestern Pacific. The Veliger 5(1):33-38.
  • Millen, S.V. (1989) Opisthobranch range extensions in Alaska with the first records of Cuthona viridis (Forbes, 1840) from the Pacific. The Veliger, 32: 64-68
  • Trowbridge, C.D. (1994) Defensive responses and palatability of specialist herbivores: Predation on NE Pacific ascoglossan gastropods. Marine Ecology - Progress Series, 105: 61-70.
Authorship details
Behrens, D.W., 2006 (March 2) Stiliger fuscovittatus Lance, 1962. [In] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/stilfusc

Related messages


Re: Ercolania fuscovittata or Stiliger fuscovittatus ?

March 4, 2006
From: Kathe R. Jensen

Concerning message #15996:

Dear Bill, Cynthia and others,
Immediately after I answered the message about "Ercolania fuscovittata" in Florida, I was contacted by Jim Lance, and I admitted that I had just copied Kerry's generic placement without thinking. I never saw the species during the time I was in Florida, and of course, checking Jim's original description, the teeth are not sabot-shaped, and hence the species does not belong in Ercolania.

I am not sure that I agree with Cynthia about not transferring a species unless there is a published paper doing the formal transfer. Henning Lemche described Stiliger niger around 1936 (when Ercolania was still considered a junior synonym). This species clearly has sabot-shaped teeth, and I have been publishing on its biology as Ercolania nigra. However, various databases and checklists still insist on calling it Stiliger niger. If somebody can tell me where I can publish a paper just transferring one species from one genus to another without contributing any new scientific data, I will be happy to do so. But I really think it would be a waste of time. Lemche's original drawing of the radular teeth clearly shows that they are sabot-shaped, so it should be obvious that it is an Ercolania.

Best wishes,
Kathe

krjensen@snm.ku.dk

Jensen, K.R., 2006 (Mar 4) Re: Ercolania fuscovittata or Stiliger fuscovittatus ?. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/16016

Thanks Kathe,
And before anyone asks the change from niger to nigra is a "grammar thing", Ercolania being feminine and Stiliger masculine. As Kathe ironically comments "how appropriate for hermaphroditic animals!".
Best wishes,
Bill Rudman

Rudman, W.B., 2006 (Mar 4). Comment on Re: Ercolania fuscovittata or Stiliger fuscovittatus ? by Kathe R. Jensen. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/16016

Ercolania fuscovittata or Stiliger fuscovittatus ?

March 3, 2006
From: Cynthia Trowbridge

Concerning message #13436:

Dear Bill,

Throughout temperate and tropical areas of the world, there are numerous sacoglossan opisthobranchs that feed selectively on red algal species belonging to the order Ceramiales; these sacoglossans belong to at least three sacoglossan genera: Hermaea, Stiliger, and Elysia.

Contrary to recent discussion on the Sea Slug Forum, the Pacific specimens of Stiliger fuscovittatus Lance, 1962 clearly belong to the genus Stiliger, not to Ercolania: (1) the teeth are blade-shaped, not sabot-shaped and(2) the species eats red algae, not septate, green algae (characteristic of Ercolania spp.). To my knowledge, there are no Ercolania spp. (as currently recognized) that feed on red algae.

Please excuse me for suggesting that it may not be appropriate to switch a species to another genus in the absence of a published report, particularly if there is strong evidence that the original genus identification is deemed correct by local malacologists. Kerry's specimen may or may not have been Ercolania; with no published record of Florida tooth shape, it is hard to determine. However, there are published records of teeth, feeding, etc. of the NE Pacific species (Lance 1962, Case 1972, Trowbridge 2002, references therein).

In private communication, Jim Lance expressed his concern about your change; I expressed my concern in message #13436. I note that David W. Behrens & Alicia Hermosillo (2005) also consider the species Stiliger fuscovittatus in their recent identification book. With at least four malacologists supporting the Stiliger position based on radular and dietary evidence, I wish you would change the Ercolania fuscovittata (Lance, 1962) back to its original name for the Pacific populations.

Finally, Jim added a new algal genus to the repertoire of genera consumed by Stiliger fuscovittatus (excerpt from letter from Jim Lance to Cynthia, 31 March 2005):
"To the algal food substrates of S. fuscovittatus may be added Dasya (San Diego). Along with Callithamnion and Polysiphonia, I have personally observed rhodoplast ingestion into the alimentary tract (contrary to the opinion expressed in Morris, Abbott & Haderlie. My algal IDs were always verified by Joan Stewart at SIO."

Thank you for considering my comments. Hopefully, Kathe and Terry will respond to settle the issue.

Cordially,
Cynthia

trowbric@onid.orst.edu

Trowbridge, C.D., 2006 (Mar 3) Ercolania fuscovittata or Stiliger fuscovittatus ?. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/15996

Dear Cynthia,
I think my calling it Ercolania would count as a sin of omission. I didn't realise I had changed the  'generic placement' of the species. The first query called it Ercolania, Kerry Clark called it Ercolania, and Kathe called it Ercolania. After I received  your message I asked Kathe for advice and am still waiting. If you had sent me an email last year saying what your present one says I would have readily changed it to Stiliger. I'm afraid in some groups I need guidance - or 48 hrs in the day to check the literature! However I appreciate that as there are so few opisthobranch workers, sometimes none of us have time to respond immediately. Anyway - better late than never!

Dave Behrens has prepared a new Fact Sheet - as Stiliger fuscovittatus - and it includes a copy of Jim Lance's photo. Perhaps the Caribbean record is of a completely different species.
Best wishes,
Bill Rudman

Rudman, W.B., 2006 (Mar 3). Comment on Ercolania fuscovittata or Stiliger fuscovittatus ? by Cynthia Trowbridge. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/15996

Re: Information on Ercolania fuscovittata

April 12, 2005
From: Kathe R. Jensen

Dear Bill & Mike,
Concerning message #13234: I think that Kerry Clark collected Ercolania fuscovittata a single time in Florida, so I wouldn't exactly call it invasive. However, it probably has been introduced through human activities, but whether it has established a successful, breeding population, I don't know.

I think Kerry's record has been listed in his paper about sacoglossans as species at risk:

  • Clark, K.B. 1994. Ascoglossan (=Sacoglossa) molluscs in the Florida Keys: rare marine invertebrates at special risk. Bull. Mar. Sci. 54: 900-916.

Best wishes,
Kathe

krjensen@zmuc.ku.dk

Jensen, K.R., 2005 (Apr 12) Re: Information on Ercolania fuscovittata. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/13434

Thanks Kathe,
Bill Rudman


Re: Information on Ercolania fuscovittata

April 12, 2005
From: Cynthia Trowbridge

Dear Bill and Mike,
I just came across this message [#13234] about "Ercolania" fuscovittata. I am unclear why it is listed as Ercolania as this was described as Stiliger by Lance (1962). Not all Stiliger spp. were shifted to Ercolania spp. The radular teeth shown in Fig. 3 of the species description are not Ercolania sabot-shaped teeth.

Details about the species (feeding, distribution, etc.) are compiled in:

  • Trowbridge, C.D. 2002. Northeastern Pacific Sacoglossan Opisthobranchs: Natural History Review, Bibliography, and Prospectus. The Veliger, 45: 1-24.

Please note that Lance's original photo of this species was shown with a red alga in the background (Microcladia coulteri) ... but not one of the two genera that the species actually does eat (Polysiphonia and Callithamnion ). For more detailed information about this species, please refer to Trowbridge (2002) or an unpublished MSc thesis:

  • Case, R.M. 1972. An ecological study of Stiliger fuscovittata (Mollusca: Opisthobranchia). M.A. Thesis, San Francisco, CA. 76 pp.

In my review, I mention the hypothesis of anthropogenic introduction (p. 5) for this species. I apologize for not having photos available but hopefully someone else will.

Cordially,
Cynthia

trowbric@onid.orst.edu

Trowbridge, C.D., 2005 (Apr 12) Re: Information on Ercolania fuscovittata. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/13436

Dear Cynthia,
I'll leave Kathe to answer the Ercolania versus Stiliger question
Best wishes,
Bill Rudman


Information on Ercolania fuscovittata

March 3, 2005
From: Michael Andres

I've been trying to find more out about this little guy and wanted to know if any of you know about them. I live in Florida, USA and one of my professors said that this may be an invasive species in our area. I thought I'd do a search on the web for them because I have found several sea hares on the beach but never one of these.

I know most nudi's aren't like the sea hares but as I said, I can't find any info on Ercolania fuscovittata.
Thanks for your help,
Mike

articcatfish@aol.com

Andres, M., 2005 (Mar 3) Information on Ercolania fuscovittata. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/13234

Dear Michael,
I can't find much about Ercolania fuscovittata on the web, but there is a bit more if you search for its earlier name Stiliger fuscovittattus Lance 1962. It  grows to about 10 mm as is found on red filamentous algae such as Polysiphonia and Callithamnion. It is found down the west coast of Nth America from Alaska to Mexico, in both marine and estuarine conditions. It is fairly transparent so the colour of its food in its digestive system shows through the body wall making it well camouflaged on its algal hosts. There is a photo at http://slugsite.us/bow/pan/stiliger.html.

It is reported as a possible invader in Texas & Florida but I have no information on that. If someone can help us out with photos and any information on it from either the west coast or the Caribbean I would be grateful.

  • Behrens, D.W. (1991) Pacific Coast Nudibranchs. 2nd Ed. SEa Challengers, Monterey. 107pp.
  • Millen, S.V. (1989) Opisthobranch range extensions in Alaska with the first records of Cuthona viridis (Forbes, 1840) from the Pacific. The Veliger, 32: 64-68
  • Trowbridge, C.D. (1994) Defensive responses and palatability of specialist herbivores: Predation on NE Pacific ascoglossan gastropods. Marine Ecology - Progress Series, 105: 61-70.

Best wishes,
Bill Rudman

Rudman, W.B., 2005 (Mar 3). Comment on Information on Ercolania fuscovittata by Michael Andres. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/13234