(Adams & Reeve, 1850)
Tropical western Pacific.
Heron Island, Great Barrier Reef, Queensland, June 1983. UPPER: Large animal (12mm long) with orange markings on white lines. LOWER: Animals (7-5mm long alive) clustered on food sponge, Dysidea sp.. Note animals half embedded in depressions they have eaten out in sponge colony.
PHOTOS: Bill Rudman.
This small, but brilliantly coloured species, seldom grows larger than 7mm. It is often found clustered in groups on a blue sponge Dysidea sp..
Although usually animals have three white lines, as their name suggests, sometimes the lines can be broken into a series of dashes, or the outer two lines can be absent (Rudman, 1986). Sometimes there are yellow or orange markings on the white lines.
See the Noumea purpurea Colour Group Page to compare this species with others of similar colour.
•Rudman, W.B. (1984) The Chromodorididae (Opisthobranchia: Mollusca) of the Indo-West Pacific: a review of the genera. Zoological Journal of the Linnean Society 81: 115-273.
•Rudman, W.B. (1986) The Chromodorididae (Opisthobranchia: Mollusca) of the Indo-West Pacific: Noumea purpurea and Chromodoris decora colour groups. Zoological Journal of the Linnean Society 86(4): 309-353.
Johnson, R.F. & Gosliner, T.M. (1998). The genus Pectenodoris (Nudibranchia: Chromodorididae) from the Indo-Pacific, with the description of a new species. Proceedings of the California Academy of Sciences, 50(12): 295-306.
Rudman, W.B., 1998 (December 17) Pectenodoris trilineata (Adams & Reeve, 1850). [In] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/pecttril
March 30, 2010
From: Franco De Lorenzi
Dear prof. Rudman
these three specimens, all from Lembeh, have in common general features probably of Pectenodoris trilineata but the yellow colour line on 2 of the nudibranchs in photo give me some doubts.
Are these variations? In the first photo, it is possible to see another same nudibranch beneath the sand. I relate this in case it may help.
Locality: Lembeh strait, 16 metres, Indonesia, indopacific ocean, 22-24 august 2008, black sand. Length: 10 mm. Photographer: Franco De Lorenzi.
Thanks a lot.
Franco De Lorenzi, 2010 (Mar 30) Pectenodoris trilineata from Lembeh. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/23417
If you look through earlier messages on this species you will see that Pectenodoris trilineata shows quite a lot of variation in the presence of yellow on the white lines. Sometimes there are really only two lines.
Your upper photo illustrates quite well how difficult it can be to find out what these animals are feeding on. The animal you describe as being buried in the sand is almost certainly burrowing and feeding on its favourite food - a greyish-blue species of Dysidea. I suspect all the background in that photo, which looks like sand, is a layer of Dysidea over which are scattered grains of sand and shell grit. In a close-up, I have ringed a small part of the sponge colony which is raised above the rest. In this bit you can see the sponge structure fairly clearly. Have a look at the sponges on the Fact Sheet for comparision.
October 22, 2008
From: Marcel Tanke
Attached are two pictures of Pectenodoris trilineata from Bali.
Locality: Tulamben, Bali, 10 m, Indonesia, 2 October 2008, Black sand. Length: 2 cm. Photographer: Marcel Tanke.
firstname.lastname@example.orgTanke, M.A., 2008 (Oct 22) Pectenodoris trilineata from Bali. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/21983
December 11, 2007
From: David Mullins
Herewith 2 pics demonstrating some of the variation possible within the Pectenodoris trilineata species.
The specimen in the upper photo exhibits the mantle pattern we usually encounter and after which it was obviously described. The lower photo shows a specimen with only a single central dorsal white stripe bisected with orange dashes. Compare this individual with the topmost photo on the factsheet for Pectenodoris trilineata. Without the 2 outer lateral stripes one could almost be looking at the same creature.
The individuals submitted here were found only about a metre apart and both were approx. 6 to 8 mm in length.
I often ponder the strange circumstance whereby some species are so very variable in outward "ornamentation", often to the point of being considered another species (by the uninitiated), and yet others maintain such a strict constancy of appearance.
Locality: Inner Gneerings, Mooloolaba, Sunshine Coast,, 15 metres, Queensland, Australia., Pacific Ocean., 01 December 2007, Rocky Reef. Length: 6 to 8 mm. Photographer: David Mullins.
email@example.comMullins, D.A., 2007 (Dec 11) Some variation in Pectenodoris trilineata. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/21283
Thanks for these. The genetics of colour variation is a fascinating field of study. Very little has been done on opisthobranchs but I do know there is a vast literature on butterflies and moths and some on land snails [and I presume many other groups as well]. I guess the reason for this is that it is much easier to keep many generations of butterflies and landsnails alive in captivity than it is to keep opisthobranchs.
November 2, 2007
From: Heidi Hösel
we observed this unusual association during our stay in Lembeh. The tiny "rider" seemed to be sucked on the nudibranch and did not move during the time watched and took pictures of it. Although I think I saw some kind of rhinophores, other anatomical features (gills, foot/mantle) that would identify the rider clearly as another nudibranch are missing. Its size was about 1 - 3 mm maximally, so I assume the rider could be a nudibranch (Gymnodoris?) larval stage. Could you please explain what my husband and I have seen?
Locality: Lembeh strait, TK2, about 18 m, Indonesia, pacific, August 2006, rubble. Length: 10 - 15 mm (for the Pectenodoris ). Photographer: Heidi Hösel.
Thank you for your information in advance
Hösel, H., 2007 (Nov 2) Parasite or joy ride? on Pectenodoris trilineata. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/21011
The tiny hitchhiker could indeed be a juvenile Gymnodoris, perhaps G. rubropapulosa. I often wonder what the juveniles of some of the rapacious nudibranch 'hunters' eat. We assume that juveniles feed on smaller prey than adults but many seem to be 'hard wired' to feed on specific prey animals and if they are only available in large sizes perhaps the result is as in your photo, they bite in and hang on for a ride.
It reminds me of Ross Gudgeon's message [#15816] which shows a small Roboastra gracilis beginning to devour a much larger Nembrotha kubaryana.
I'll add it to the opisthobranch feeding page for future reference.
January 3, 2007
From: Erwin Kodiat
This one was taken in North Sulawesi. It is so tiny that last year when I saw it in Bali, I thought it was a juvenile, but the in one occasion in Seraya, Bali, I saw this kind of nudi this size laying eggs, so I guess it is already in adult form. But since my pocket camera can not take the picture of this, I can't send you any photos. But luckily, when I went to North Sulawesi, I got a borrowed 100 mm macro lens, I can take this picture. Can you help me ID this?
Locality: Tanjung Popoh, North Sulawesi, Indonesia, Gulf of Manado, 30 October 2006. Length: 1.5 cm. Photographer: Erwin Kodiat.
firstname.lastname@example.orgKodiat, E., 2007 (Jan 3) Pectenodoris trilineata from Indonesia. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/18938
This is indeed a small species of chromodorid, seldom growing more than about 10 mm in length. It is Pectenodoris trilineata.
February 13, 2006
From: Bruce Wilkie
I have not been able to ID these four I found feeding on a sponge.
Locality: Manta Bommie Point Lookout, North Stradbroke Island, 10 metres, Queensland Australia, Pacific ocean, 31 December 2005, rocky reef with sponges, hard & soft corals. Length: 10 mm. Photographer: Bruce Wilkie
Could you please ID?
Wilkie, B., 2006 (Feb 13) Feeding Pectenodoris trilineata from sthn Queensland. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/15792
This is Pectenodoris trilineata. They are quite large specimens and its nice to have some with the heavy orange pigmentation, Usually they are smaller with white lines, sometimes with orange spots in the white lines. Apparently as they grow larger the orange expands to cover most of the white.
January 22, 2004
From: Peter Zimmermann
I took this picture in June 2003 in about 20m depth at Kirby's Rock in Anilao, Philippines. Is this nudibranch Durvilledoris similaris?
Thanks for your answer.
Peter.Zimmermann@STRATEC.comZimmermann, P., 2004 (Jan 22) Pectenodoris trilineata from Philippines. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/11982
This nice photo sjows its sponge food very clearly. It certainly looks quite like Durvilledoris similaris, but as its name implies, there are a number of very 'similar' looking species. This is Pectenodoris trilineata. See the Noumea purpurea Colour Group Page to compare this species with others of similar colour.
August 5, 2000
From: Mike Miller
Am attaching a pic of Pectendoris trilineata to complement the image
already on your site. It would seem the animals in the attached pic are also grazing on the same prey sponge Dysidea sp.?
Location: Divesite - Mapating. Batangas, Philippines, May 2000. Depth: 20 ft.
email@example.comMiller, M., 2000 (Aug 5) Pectenodoris trilineata & prey sponge. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/2826
It certainly looks like the same sponge. I have nearly always found P. trilineata in numbers clustered on and in burrows it has apparently eaten in the sponge colony, just as your photo shows.
March 23, 2000
From: Lindsay Warren
This specimen was found by Rich Smith and Doug Philpott at 6.30am on 6 June 1999 at a depth of 8.3 m in an exposed position on dead table coral on Pulau Hoga [Tukang Besi Archipelago, SE Sulawesi, Indonesia - Operation Wallacea]. Size: 6 mm.
It looks similar to Pectenodoris trilineata but the amount of orange in the notum bands made us suspicious. The body and foot are overall strong purple with
a thin white rim to the foot and mantle edge. The rhinophores are a deeper orange than the notum bands with the same colour repeated in the gills.
Photos: Lindsay Warren.
What are your thoughts on this?
All the best
firstname.lastname@example.orgWarren, L., 2000 (Mar 23) Pectenodoris trilineata from Sulawesi. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/2137
You are right to be suspicious where chromodorids are concerned but I am pretty sure this fits in the colour range of Pectenodoris trilineata.
December 17, 1998
From: Erwin Koehler
These photos were taken at Dauin, Negros, Philippines this October and are the last ones of one (!) dive, looking for seahorses.
E.Koehler@deutschepost.deKoehler, E., 1998 (Dec 17) Pectenodoris trilineata from Philippines. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/400
This pretty little animal Pectenodoris trilineata. It is an appropriate time to be posting photos of Pectenodoris as I have just received a reprint from Rebecca Johnson and Terry Gosliner (see references at top of page) describing a second species of this genus of small chromodorids, which I erected in 1984.