Hypselodoris maculosa
(Pease, 1871)

Order: NUDIBRANCHIA
Suborder: DORIDINA
Family: Chromodorididae

DISTRIBUTION

Found throughout the tropical western Pacific and Indian Oceans.

PHOTO

Upper: Heron Is, Great Barrier Reef, Queensland, May 1981. Lower: Mbudya Is, Dar es Salaam, Tanzania, November 20 1976, 18mm long alive. Photos: Bill Rudman.

RELATED TOPIC

See also Hypselodoris cf. maculosa

The colour pattern is complicated and very variable. One of the simplest patterns is illustrated by the Tanzanian specimen [lower right photo]. The background colour of the mantle is a pale milky orange-brown. Around the anterior of the mantle is a broad translucent pinkish-purple margin with scattered white and darker pinkish-purple spots. At the posterior end the margin is similarly coloured but the band is not as broad. From the level of the rhinophores back to the gill pocket, there is a broad orange band at the edge. On the inside edge of the orange band, at the junction with the milky orange-brown central region, there is a series of reddish-purple streaks running back from the rhinophore pocket to the gill pocket on each side. In the gaps between the reddish-purple streaks are a pair of white streaks, one inside and one outside the red. The orange band appears wider adjacent to the red streaks because the outer white line of the alternating pair of white lines narrows the orange band on each side. Running down the central part of the mantle are four narrow white lines. There are five small dark pinkish-purple spots down the midline between the gills and rhinophores. The rhinophore stalks are translucent white and the clubs are white with a broad orange band at the base and another just below the tip. The simple gills are translucent white with a deep orange line down the outer edge and an orange tip. The bottom half of each gill is translucent orange. The sides of the body and the foot are a translucent pinkish-purple with a colourless band at the edge. On the sides of the body there are white lines and streaks running parallel to the edge of the foot and some pinkish-purple spots. On the posterior part of the foot extending beyond the end of the mantle there are scattered white spots and around the inside edge of the colourless translucent margin are a row of elongate pinkish-purple streaks.

Many variations are illustrated in other messages on this page. For example, the white lines on the back can be broken into a series of short streaks and there can be many pinkish-purple spots on the mantle and also the posterior part of the foot. Also the orange mantle border can be very pale, it can be reduced to a thin line, and it can be accompanied by a series of reddish spots. There can also be one, two or three orange bands on the rhinophore club. Many colour variants are described in an earlier publication (Rudman, 1986).
.
The mantle is elongately oval, widening at the anterior end to give a spatulate appearance. The mantle overlap is very reduced, especially along the sides, and the foot extends some distance behind the posterior limit of the mantle. The animal is relatively high and narrow and the simple gills are arranged in a circle, open posteriorly, around the anus. There is a large aggregation of mantle glands opening at the edge, around the posterior end of the mantle. A few small mantle glands are found on each side adjacent to the rhinophores but they are absent elsewhere.

Originally described from Tahiti, this species has wide Indo-West Pacific distribution. Other names which have been used for this species include Chromodoris decorata (Risbec, 1928) and Glossodoris xishaensis Guang-Yu, 1975).

References:
• Guang-Yu, L, 1975. Opistobranchia from the intertidal zone of Xisha Island, Guangdong Province, China. Studia Marina Sinica, 10: 141-154, pls 1, 2.
• Pease, W.H. (1871). Descriptions of new species of nudibranchiate Mollusca inhabiting Polynesia. No. 2. American Journal of Conchology, 7(1): 11-19, Pls 3-9.
• Risbec, J., 1928. Contribution à l'etude des nudibranches Néo-Calédoniens. Faune des Colonies Françaises, 2(1): 328, pls 1-12.
• 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.

Authorship details
Rudman, W.B., 2003 (October 4) Hypselodoris maculosa (Pease, 1871). [In] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/hypmacu

Related messages


Hypselodoris maculosa from the Solomon Ids

September 4, 2008
From: Barbara Hanchard

Bill,

Bruce Potter suggests this might be Hypselodoris maculosa. Another one of the chromodorids we found on the 12 Jan 2006 wreck dive along with H. zephyra, H. krakatoa, Mexichromis multituberculata and others [see message #21863 ].

Locality: Tommy Chan Wreck, Ranadi, 35 meters, Solomon Islands, Pacific Ocean, 12 January 2006, Wreck. Length: 30 mm. Photographer: N.Barbara Hanchard.

Colour was as appears in the photo, a blinding white mantle and no noticeable striation patterns. Sorry no other photos or aerial views which would have been handy.

Barbara

barbara.hanchard@ffa.int

Hanchard, N.B., 2008 (Sep 4) Hypselodoris maculosa from the Solomon Ids. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/21864

Dear Barbara,
If your last message [#21863] wasn't enough to confirm these animals were eating Euryspongia, then this message must surely do so. We don't have much evidence on the food of Hypselodoris maculosa but Bruce Wilkie's  [#20944] and Scott Johnson's [#2155] messages show that it eats Euryspongia. So even though your animal is not feeding on a sponge in your photo, its presence with the other three species, suggests they have been attracted by a common food. Very interesting!

Since the wreck was only 4 months old, it would suggest these four species have grown rather quickly from larvae, as I can't imagine they have all crawled there from other places.

Best wishes,
Bill Rudman

Rudman, W.B., 2008 (Sep 4). Comment on Hypselodoris maculosa from the Solomon Ids by Barbara Hanchard. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/21864

Hypselodoris maculosa from Bali

February 13, 2008
From: Mirjam Broos

Hello Bill,

Can you confirm if this nudi is a Hypselodoris maculosa?

Locality: Tulemben drop off, Indonesia, Bali, Indian Ocean, 02 april 2007. Photographer: Geert Prast.

Thanks,
Mirjam

mirjam.broos@planet.nl

Broos, M., 2008 (Feb 13) Hypselodoris maculosa from Bali. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/21276

Dear Mirjam,

Yes this is one of the colour variations of that species.

Best wishes,
Bill Rudman

Rudman, W.B., 2008 (Feb 13). Comment on Hypselodoris maculosa from Bali by Mirjam Broos. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/21276

Hypselodoris maculosa feeding

October 16, 2007
From: Bruce Wilkie


Hi Bill,
Here is a feeding record of Hypselodoris maculosa. Its not the most brilliant photo of the animal but it shows the sponge quite well.

Locality: Flat rock, Point lookout, Nth Stradbroke island, Queensland, Australia 10 mts, 4 December 2005, Rocky reef, hard and soft corals, sponges. Length: 10 mm. Photographer: Bruce Wilkie.

Many thanks,
Bruce Wilkie.

brucedwilkie@yahoo.com.au

Wilkie, B, 2007 (Oct 16) Hypselodoris maculosa feeding. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/20944

Dear Bruce,

It may not be the most brilliant photo of the animal but it is a brilliant photo of its food sponge. This is a dysideid and I suspect it is a species of Euryspongia, but I will need to confirm that. The only other information we have of feeding in this species is a photo in Scott Johnson's message [#2155] showing the fibrous skeleton of a colony of Euryspongia.

Best wishes,
Bill Rudman

Rudman, W.B., 2007 (Oct 16). Comment on Hypselodoris maculosa feeding by Bruce Wilkie. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/20944

Colour form of Hypselodoris maculosa from the Philippines

October 8, 2007
From: James A. Loyola


Hi Bill.
Here is another nudi i cant find a match for in my books. I think its a Hypselodoris and looks similar to the Hypselodoris alboterminata posted in this forum. However, the rhino is different and this one has spots on the stripes. Hope you can identify this one for me. Thank you.

Locality: Kaputian Beach, Samal Island, 30-40 feet, Davao, Philippines, Pacific Ocean, 29 September 2007, coral rubble. Length: 0.5 inches. Photographer: James A. Loyola.

James A. Loyola

jaloyola88@yahoo.com

James A. Loyola, 2007 (Oct 8) Colour form of Hypselodoris maculosa from the Philippines. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/20892

Dear James,

There are a number of chromodorids with white longitudinal lines and white spots at the posterior and anterior ends of the mantle like H. alboterminata. My first thought when I saw your photos was Pectenodoris aurora because of the rows of purple spots bordered with white lines, but they are in the wrong place.

I am pretty sure this is a colour form of Hypselodoris maculosa. Have a look at my comments about a very similar animal from Sulawesi in a message from Ken Tucker [#19361]

Best wishes,
Bill Rudman

Rudman, W.B., 2007 (Oct 8). Comment on Colour form of Hypselodoris maculosa from the Philippines by James A. Loyola. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/20892

Hypselodoris maculosa from Sri Lanka

September 27, 2007
From: Anouk Houben

I found these nudibranch on the same divesite off the South coast of Sri Lanka. Although the couple of them is a lot brighter in colour, their colour pattern is identical to the single snail. Could they be Hypselodoris maculosa, without the maculae among the dorsal lines?

Locality: Prinz Heinrich Patch, Weligama, 16 m, Sri Lanka, Indian Ocean, February/April 2007, rock formations. Length: 3 cm. Photographer: Anouk Houben.

Best regards,
Anouk

nashiman@lankacom.net

Houben, A., 2007 (Sep 27) Hypselodoris maculosa from Sri Lanka. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/20814

Dear Anouk,

Yes this is H. maculosa. Usually the white spots are restricted to the anterior and posterior parts of the mantle as in your animals, which are very similar in colour to an animal on the Fact Sheet which I photographed in Tanzania in the western Indian Ocean.

It is very interesting to get such good photos of animals from Sri Lanka. I hope this message and your earlier one [#20757] are just the start of many mesages from Sri Lanka. What is particularly interesting about the Sri Lankan fauna is that some of the earliest descriptions of nudibranchs from the Indo-West Pacific were from animals collected and described by Edward Kelaart from Ceylon [Sri Lanka] in the second half of the 1800s. Kelaart was the Doctor in charge of the British colonial troops in Ceylon at that time and gave as his justification for studying nudibranchs was that:
"there is nothing like the careful study of God's works to divert the mind from the contemplation of diseased organic bodies, especially in this unhealthy and monotonous station....."

The importance of Kelaart's names is that because they are some the earliest names, we need to know which species they apply to as they may be older than names currently in use in other parts of the Indo-West Pacific.

Best wishes,
Bill Rudman

Rudman, W.B., 2007 (Sep 27). Comment on Hypselodoris maculosa from Sri Lanka by Anouk Houben. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/20814

Hypselodoris maculosa from New Caledonia

June 28, 2007
From: Pieric Urvoy

Dear Bill,
I'm not quite sure it's Hypselodoris maculosa. Do you confirm ?
Found on the East Coast of New-Caledonia. The temperature was 24 °C. I found it at 9:40am.

Locality: Hienghen, New Caledonia, Pacific Ocean, 25 November 2006. Length: 15-20 mm. Photographer: Pieric Urvoy.

Sincerly,
Piéric

sharkus@free.fr

Urvoy, P., 2007 (Jun 28) Hypselodoris maculosa from New Caledonia. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/19465

Dear Pieric,

Yes this is H. maculosa. In fact it looks very similar to the painting in Risbec's original description of this species from New Caledonia in 1928 [Plate 7, fig. 4], which I have copied alongside.

Best wishes,
Bill Rudman

Rudman, W.B., 2007 (Jun 28). Comment on Hypselodoris maculosa from New Caledonia by Pieric Urvoy. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/19465

Colour forms of Hypselodoris maculosa

May 18, 2007
From: Colin Ogden

Hi Bill,
I know this discussion dates back to 1999, but I would like to add one more query to the discussion. When different colour forms of a species exist in the same place, will the different colour forms mate with each other or will they mate only with the same colour form. We have both colour forms of the Hypselodoris maculosa here, the typical form is more abundant (upper photo). We occasionally find the colour form as in the lower photo. This photo shows 3 of the unusual form together. It appears that the 2 nudis in the growth are just about to, or have just completed their mating, while the third nudi is arriving on the scene. Also the unusual colour form appears to normally be about 5 to 10 mm bigger than the normal one.

Locality: Sodwana Bay, 22 matres, South Africa, Indian, 18 February 2007, reef. Length: 30mm. Photographer: Colin Ogden.

Regards
Colin

scubao@iafrica.com

Ogden C. M., 2007 (May 18) Colour forms of Hypselodoris maculosa. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/19512

Dear Colin,
I am happy to keep any discussion going as long as it takes. Colour in animals is a very interesting and complex topic. To keep this discussion concise, there are two major types of colour variation we can find in a species. The first is a gradual change from one colour pattern to another which is what we see in most chromodorids. Its also the sort of thing we see when people of two racial groups marry - their children show traits from both their mother and their father. The other main type of colour differentiation we find within species is called polymorphism and is where there are two or more quite distinctly different colour patterns or morphs within a species. The colour of the offspring of matings between animals from different morphs is determined by quite precise genetic rules, but whatever the colour is it will be one of the distinct morphs and not a mixture of the parent's colour patterns. Many butterflies are polymorphic like this, but I am not convinced there are any polymorphic nudibranchs.

Noumea haliclona from southeastern Australia almost fits the bill, but in this case the different morphs seemed to be geographically separate, which brings up the question of whether we should consider them subspecies rather than colour morphs.

None of this really answers your question about these colour 'forms' of Hypselodoris maculosa. The biggest problem is that we really don't know enough about them to be sure they are the same species. Often the anatomical differences are quite small and very few species have been studied in any detail. That is one reason I keep asking for photos of them 'doing things' because a different egg ribbon, or egg size, or food choice, might be a clue to differences we do not even suspect.

Best wishes,
Bill Rudman

Rudman, W.B., 2007 (May 18). Comment on Colour forms of Hypselodoris maculosa by Colin Ogden. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/19512

Hypselodoris maculosa from Lembeh Strait

May 10, 2007
From: Mike Krampf

Dear Bill

I just thought I'd share this Hypselodoris maculosa taken in Lembeh Strait.

Locality: Lembeh Strait, 30 ft, Indonesia, Celebes Sea, 28 October 2006, Fringing reef. Length: 2 cm. Photographer: Mike Krampf.

Mike

mtkrampf@yahoo.com

Krampf, M., 2007 (May 10) Hypselodoris maculosa from Lembeh Strait. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/18879

Thanls Mike,
Bill Rudman


Hypselodoris maculosa from Sulawesi

February 2, 2007
From: Ken Tucker

Dear Bill,

I've attach a photo of what assume is another variant of Chromodoris decora.

Locality: Lembeh Strait, 12 metres, Indonesia, Sulawesi, 28 Nov 2006, Dive site - Critter Hunt. Length: 2 cm. Photographer: Ken Tucker.

Ken Tucker

ken@kilili.com

Tucker, Ken, 2007 (Feb 2) Hypselodoris maculosa from Sulawesi. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/19361

Dear Ken,
As you will see f rom the C. decora colour gp Page; there are a number of chromdorids with similar colour patterns. certainly some forms of C. decora can have a median band bearing a row of purple spots, but it has no orange band on the rhinophores. The narrow body with a relatively narrow mantle skirt, and the inflated posterior end of the mantle, which houses large mantle glands, suggest that this is a photo of a species of Hypselodoris. In fact, if you have a look at Marina Poddubetskaia's message [#8338] you will fiind an identically coloured specimen of Hypselodoris maculosa  from Mauritius

Best wishes,
Bill Rudman

Rudman, W.B., 2007 (Feb 2). Comment on Hypselodoris maculosa from Sulawesi by Ken Tucker. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/19361

Hypselodoris maculosa mating

May 27, 2006
From: Bruce Wilkie

Hi Bill,
Looking through the fact sheets and messages on Hypselodoris maculosa, I noticed there were not any photos of mating. Here are some to add to your collection. Also wanting to confirm these animals are H. maculosa.

Locality: Shag Rock, Point Lookout, North Stradbroke Island., 6mts, Queensland Australia, Pacific ocean, 21 May 2006, rocky reef with sponges, hard & soft corals . Length: 15mm. Photographer: Bruce Wilkie.

Many Thanks,
Bruce Wilkie.

brucedwilkie@yahoo.com.au

Wilkie,B, 2006 (May 27) Hypselodoris maculosa mating. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/16682

Dear Bruce,

Although a bit redder than usual, this is Hypselodoris maculosa. You'll notice in both photos there is a bluish-white 'fuzzy' patches to the left of the animals. I wouldn't mind betting that this is all that is left of a sponge colony they have been eating. Not enough left to identify the sponge but it is nice to get a photo of them mating

Best wishes,
Bill Rudman

Rudman, W.B., 2006 (May 27). Comment on Hypselodoris maculosa mating by Bruce Wilkie. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/16682

Hypselodoris maculosa from the Red Sea

February 24, 2005
From: Oren Lederman


Hi Bill,

We believe this one to be a Hypselodoris maculosa.

I should also point out that right now a large partion of the reef and sandy area is covered with some kind of sea grass (Enteromorpha?) which might explain why we could find some species that we usually don't see around here.

Locality: Near the "Yetush" ( mosquito) shipwreck, Eilat Bay, Israel, Red Sea. Depth: ~22 meters. Length: ~1 cm. 17 Feb 2005. Photographer: Oren Lederman

Oren Lederman

lederman@bigmail.co.il

Lederman, O., 2005 (Feb 24) Hypselodoris maculosa from the Red Sea. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/13209

Dear Oren,
Youe have certainly found an interesting collection of animals. I can remember in Tanzania at some times of the year large beds of tangled filamentous algae developed in certain places. This provided an excellent habitat for all sorts of invertebrates, sponges, hydroids, bryozoans, all of which attracted the animals that ate them, including many nudibranchs.

I would agree that this is one of the colour forms of Hypselodoris maculosa.
Best wishes,
Bill Rudman

Rudman, W.B., 2005 (Feb 24). Comment on Hypselodoris maculosa from the Red Sea by Oren Lederman. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/13209

Hypselodoris maculosa? from Philippines

October 4, 2003
From: Yukari Sato

Hello Dr.Rudman,
Here is another puzzle from the Philippines.

Date: 20 Sep 2003
Depth: 12m
Size: approx. 10mm
Location: Lilo-an, Santander, Cebu Is, Philippines

Best wishes,
Yukari Sato

yuks@cg7.so-net.ne.jp

Sato, Y., 2003 (Oct 4) Hypselodoris maculosa? from Philippines. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/11083

Dear Yukari,
There are only a few species with red-orange bands across the rhinophore clubs, and the most likely identification in this case is Hypselodoris maculosa. However I am not totally convinced because that species usually has longitudinal white lines on the mantle. It looks a bit like Hypselodoris sp. 2 but that species has distinct white lines. It also has similarities to Hypselodoris cf. carnea. I have a page on the Forum showing a range of similarly coloured species which I call the Chromodoris decora Colour Group. I am afraid it is just a little bit different to all of them.

Perhaps someone else will have a suggestion
Best wishes
Bill Rudman

Rudman, W.B., 2003 (Oct 4). Comment on Hypselodoris maculosa? from Philippines by Yukari Sato. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/11083

Hypselodoris maculosa in Bali?

September 1, 2003
From: Jukka-Pekka Salmenkaita

Dear Bill,

I found this little specimen (about 15mm) in "SD Point", Nusa Penida, Bali, Indonesia in July 24th, 2002. The depth was around 12 meters. I'd guess it is Hypselodoris maculosa - how would you identify it?

Best regards,
Jukka-Pekka

jsalmenk@cc.hut.fi

Salmenkaita, J-P., 2003 (Sep 1) Hypselodoris maculosa in Bali?. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/10619

Dear Jukka-Pekka,
Yes this is Hypselodoris maculosa.
Best wishes,
Bill Rudman


Hypselodoris maculosa from Christmas I., E. Kiribati

June 25, 2003
From: Don Barclay


Hello Bill,

Here's a photo of Hypselodoris maculosa, I believe.

Data: 24 May 2003, early afternoon, Eel Pit dive site northwest of London, Christmas Island, Line Islands, eastern Kiribati; crawling on top of dead coral head.

Depth: 15m
Length: ~7mm

Take care,
Don

barclay@txucom.net

Barclay, D., 2003 (Jun 25) Hypselodoris maculosa from Christmas I., E. Kiribati. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/10095

Thanks Don,
Bill Rudman


Hypselodoris maculosa from Egypt

March 14, 2003
From: Marina Poddubetskaia


Dear Bill,
Here is a record of Hypselodoris maculosa from the Red Sea. I found 2 specimens during my diving cruise to Brothers Islands, but photos are a bit blurred because of the surge.

Upper Photo (taken in the tank):
Date: February 12, 2003
Location: Brothers Islands, Egypt, Red Sea
Site: Numidia, Big Brother
Depth: 10m
Size: 20-25mm

Lower Photo:
Date: February 13, 2003
Location: Marsa Alam, Egypt, Red Sea
Site: Elphinstone
Depth: 16m
Size: 20-25mm
Photos: Marina Poddubetskaia - Nembro website

Best wishes,
Marina.

nembro@nembro.info

Poddubetskaia, M., 2003 (Mar 14) Hypselodoris maculosa from Egypt. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/9266

Thanks Marina,
Bill Rudman


Hypselodoris maculosa from Mauritius

November 6, 2002
From: Marina Poddubetskaia

Dear Bill,
Here are some photos of Hypselodoris maculosa from Mauritius.

Date: October 16, 2002
Location: Pereybere, Mauritius, Indian Ocean
Site: Grand Aquarium
Depth: 10m
Size: 13-15mm
Photos: Marina Poddubetskaia - Nembro website

Best wishes,
Marina.

nembro@nembro.info

Poddubetskaia, M., 2002 (Nov 6) Hypselodoris maculosa from Mauritius. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/8338

Dear Marina,
Thanks for these photos. I am not sure if it has been recorded from Mauritius before, although it is known from Africa. The yellow sponge it is on is of interest, as it may turn out to be one of its food sponges. Of course it could just be something that the slug is crawling over so we will just have to keep a note of any records of it on a yellow sponge in the future.
Best wishes,
Bill Rudman


Hypselodoris maculosa from North Sulawesi

October 29, 2002
From: Marli Wakeling


Hi Bill,
Here's a fun photo from Bangka Island, off the North coast of Sulawesi. As you can see, this tiny critter is going for a walk on a scorpion fish's dorsal fin. I wonderered if it tickled! I think it is Hypselodoris maculosa

Location: Bangka Island, North Sulawesi
Depth: 60 feet
Length: 10 mm
Date: July, 2002
Photo by: Marli Wakeling

Cheers,
Marli

scubamarli@excite.com

Wakeling, M., 2002 (Oct 29) Hypselodoris maculosa from North Sulawesi. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/8296

Dear Marli,
Now and again I have been sent a photo showing a nudibranch crawling over a fish, but not for posting on the Forum. Perhaps I should have, because although my memory's not perfect, I am pretty sure the fish has usually been a scorpaenid. perhaps its just because they sit around looking like the background for much of thr time.
Best wishes,
Bill


Hypselodoris maculosa? from SE Sulawesi

July 8, 2002
From: Lindsay Warren

Dear Bill
I wonder if you could help me with this chap. I found this specimen (OS0142) at a depth of 59ft on 20 May 1999 on Pulau Hoga, Tukang Besi Archipelago, SE Sulawesi. L:10mm. Initially I thought it was simply a colour variation of Hypselodoris maculosa but now I have my doubts having reread a Sea Slug Forum posting from Terry Gosliner (Gosliner, T., 1999 (December 18) in which he states "In H. maculosa, the glands are interrupted in the middle region of the body."

As you can see in OS0142, there are no mantle glands along the anterior and posterior mantle, only down the sides. Also, the white rhinophores with translucent bases have 3 orange bands and are tipped in orange. I think I am right in saying that H. maculosa rhinophores are usually tipped in white. I would be most interested to hear your thoughts on this one.

Many thanks for your help.
All the best
Lindsay

alldcl@compuserve.com

Warren, L., 2002 (Jul 8) Hypselodoris maculosa? from SE Sulawesi. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/7063

Dear Lindsay,
This is an interesting point. If you look at John Hicks photos from Christmas Island you can clearly see an animal with mantle glands as described by Terry. However your photo, and others on the Forum certainly show glands down each side - whether there are glands anteriorly and/or posteriorly are difficult to see in the photos. When I revised this species many years ago I decided that the number of orange-red bands on the rhinophore clubs was variable, ranging from one to three. It is of course possible that there are in fact 3 species in the complex. Certainly your 3 banded form has glands down the sides of the mantle, and John Hick's one-banded form has no glands down the side. I will have to check the 2-banded form.

Certainly an interesting little puzzle.
Cheers,
Bill Rudman

Rudman, W.B., 2002 (Jul 8). Comment on Hypselodoris maculosa? from SE Sulawesi by Lindsay Warren. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/7063

Hypselodoris maculosa from Christmas Island

May 11, 2002
From: W.B. Rudman

Here are some further photos of Hypselodoris maculosa from John Hicks' Christmas Island, Indian Ocean collections. In the lower left photo the mantle glands can be clearly seen in aggregations alongside the rhinophores, and around the posterior end.

PHOTOS: UPPER: AM C128203, 29 March 1981, 8-10 m, 17 mm long alive, Christmas Is., Indian Ocean. LOWER LEFT: AM C129117, 25 April 1981, north arm of Cantilever, 10 m, 14 mm long. Christmas Is., LOWER RIGHT: AM C126501, 18 mm long alive. 13 November 1980, south arm of Cantilever, 7.5m, on coral rock, Christmas Is. PHOTOS: John Hicks
Best wishes,
Bill Rudman

Rudman, W.B. , 2002 (May 11) Hypselodoris maculosa from Christmas Island. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/6597

Hypselodoris maculosa from Christmas Island

May 2, 2002
From: W.B. Rudman

Here is a photo of Hypselodoris maculosa from John Hicks' Christmas Island, Indian Ocean collections.

PHOTO:
CI31-01, Christmas Is., Indian Ocean. Photo: John Hicks

Best wishes,
Bill Rudman

Rudman, W.B. , 2002 (May 2) Hypselodoris maculosa from Christmas Island. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/6623

Hypselodoris maculosa - colour variation

February 21, 2002
From: Stuart Hutchison


Bill,
Here are a pair of Hypselodoris maculosa from Bali, Indonesia. They were a dime a dozen at around 5-15m in the sand and on algae covered rocks from Oct 2001. Typical sizes were 20-30mm.
Stuart

stuart@stuarthutchison.com.au

Hutchison, S., 2002 (Feb 21) Hypselodoris maculosa - colour variation. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/6259

Thanks Stuart,
Bill Rudman


Hypselodoris maculosa laying eggs

November 30, 2001
From: Julie Marshall


Dear Bill,
Last year Scott Johnson sent photos to the Forum showing various colour forms of Hypselodoris maculosa and a photo of one animal laying a pale pink coloured spawn mass. At the time you asked if anyone had other photos of this species laying eggs. This animal from Heron Island [Great Barrier Reef] laid a white egg ribbon in the laboratory. This animal was 25 mm in size.

Best wishes,
Julie Marshall

juliemarshall@netspace.net.au

Marshall, J., 2001 (Nov 30) Hypselodoris maculosa laying eggs. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/5746

Thanks Julie,
I guess it's going to take us a while to accumulate enough information to see whether there is any significance in white and orange egg masses. Certainly worth checking out in future. I really need to check back through my field notes for any observations on egg ribbons.
Best wishes,
Bill Rudman

Rudman, W.B., 2001 (Nov 30). Comment on Hypselodoris maculosa laying eggs by Julie Marshall. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/5746

Hypselodoris maculosa from the Seychelles

June 15, 2001
From: Erwin Köhler

Dear Bill,
This one was made by Frank Gloystein (Frank.Gloystein@t-online.de) at the Seychelles, Bird Island on March 17, 2001, length about 1 cm, depth about 17 m.
Erwin

Erwin@medslugs.de

Köhler, E., 2001 (Jun 15) Hypselodoris maculosa from the Seychelles. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/4565

Dear Erwin,
This is Hypselodoris maculosa.
Best wishes,
Bill Rudman

Rudman, W.B., 2001 (Jun 15). Comment on Hypselodoris maculosa from the Seychelles by Erwin Köhler. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/4565

Hypselodoris maculosa from Thailand

January 24, 2001
From: Erwin Koehler

Dear Bill,
Here is an unknown from Thailand,
Koh Ha Noi, divesite "Koh Ha Noi", depth 12m, size 6mm, date Dec. 27, 2000
Please excuse the poor quality, it was pretty small - can you help with an ID?
Erwin

Medslugs.Koehler@t-online.de

Koehler, E., 2001 (Jan 24) Hypselodoris maculosa from Thailand. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/3602

Dear Erwin,
I am pretty sure this is a juvenile of Hypselodoris maculosa. The purple spots and the red bands on the rhinophores are often characteristic of juveniles of this species.
Best wishes,
Bill Rudman

Rudman, W.B., 2001 (Jan 24). Comment on Hypselodoris maculosa from Thailand by Erwin Koehler. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/3602

Colour variation in Hypselodoris maculosa

March 26, 2000
From: Scott Johnson

Hi Bill,

Attached are some of the forms of Hypselodoris maculosa found in the Marshall Islands. The smaller specimens (less than 10mm) E067-10 and E017-10 [lower photos]look similar to a couple of the Hypselodoris cf. maculosa pictured on the site. Specimens here vary from red to purple dorsal spots, and from one (in young animals) to three bands on the rhinophores. I admit I still keep these animals split up under two species numbers, one of which tends to have purple spots and two rhinophore bands, and the other with more reddish or reddish violet spots and three rhinophore bands. There is some overlap and I agree they are probably the same. However, I keep them separate because whenever I find them paired, it is always like individuals that are paired up (as in E067-11 , on a nearly eaten out sponge colony), and that's kept me suspicious that these could be more than simply color forms. I've been burned before by failing to notice that what I was treating as a single species was really two.

Scott

johnson@kmr.ll.mit.edu

Johnson, S., 2000 (Mar 26) Colour variation in Hypselodoris maculosa. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/2154

Dear Scott,
Thanks for the photos of variation. i tried to match number of red bands on rhinophores without any success but I agree it's worth keeping specimens well enough documented to be able to go back and check if someone discovers a good character.

I have posted some of your photos, including the egg ribbon one and the sponge-feeding one on a separate page to avoid having to make them too small.

Best wishes,
Bill Rudman.

Rudman, W.B., 2000 (Mar 26). Comment on Colour variation in Hypselodoris maculosa by Scott Johnson. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/2154

Hypselodoris maculosa Colour variation (2)

March 26, 2000
From: Scott Johnson

Here are some more of Scott Johnson's photos which accompanied his message about colour forms of Hypselodoris maculosa found in the Marshall Islands. Accompanying his message was the following note about the two on the right on the almost completly eaten sponge colony:
I keep [the the colour forms] separate because whenever I find them paired, it is always like individuals that are paired up (as in E067-11, on a nearly eaten out sponge colony), and that's kept me suspicious that these could be more than simply color forms. .. Scott Johnson.

Note also the photo of an animal egg laying. If anyone has photos of any colour form laying eggs it would be good to compre them with Scott's photo
Bill Rudman.

johnson@kmr.ll.mit.edu

Johnson, S., 2000 (Mar 26) Hypselodoris maculosa Colour variation (2). [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/2155

Re: Hypselodoris cf. maculosa from Sth Africa

December 15, 1999
From: Terry Gosliner

Dear Bill.
The Hypselodoris that you posted this morning looks to me like H. maculosa. We have found some Indian Ocean specimens with purple spots. They do not differ internally from typical H. maculosa.

Best wishes,
Terry.

tgosline@calacademy.org

Gosliner, T., 1999 (Dec 15) Re: Hypselodoris cf. maculosa from Sth Africa. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/1679

Thanks Terry,
It was the prominence of the purple spots which puzzled me but I agree that the most likely bet is that it is a colour form of H. maculosa.

Here is a photo of an animal I found in Tanzania [Mbudya Is, Dar es Salaam, Tanzania, November 20 1976, 18mm long alive] which looks more like the western Pacific colour than Valda's Sth African animal.
Best wishes,
Bill Rudman.

Rudman, W.B., 1999 (Dec 15). Comment on Re: Hypselodoris cf. maculosa from Sth Africa by Terry Gosliner. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/1679

Hypselodoris from South Africa

December 14, 1999
From: Valda Fraser

Dear Bill
I have searched through the Hypselodoris list and nothing looks like this to me. Perhaps I've overlooked it. Please tell me what it is.

Locality: South Coast KwaZulu-Natal, SOUTH AFRICA. Scottburgh - 24m. Date: 28 November 1999. Size: 35mm

Regards
Valda Fraser

iti04937@mweb.co.za

Fraser, V., 1999 (Dec 14) Hypselodoris from South Africa. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/1628

Dear Valda,
I've looked through all my Hypselodoris lists and likewise can't find a name for this animal. It has similarities to Hypselodoris maculosa in having white longitudinal lines on the mantle and transverse orange bands on the rhinophores, but the prominent purple spots seem unique.

Best wishes,
Bill Rudman.

Rudman, W.B., 1999 (Dec 14). Comment on Hypselodoris from South Africa by Valda Fraser. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/1628

Hypselodoris maculosa from Vanuatu

December 1, 1999
From: Vinka Stenhouse

Dear Bill,

Could you identify this nudibranch from Vanuatu please. The details are: Peyrole, 15 metres depth,. 2cm long, January 1998.

Yours sincerely,

Vinka Stenhouse.
Santo.
Vanuatu.

Stenhouse, V., 1999 (Dec 1) Hypselodoris maculosa from Vanuatu. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/1603

Dear Vinka,
This is Hypselodoris maculosa.
Best wishes,
Bill Rudman.

Rudman, W.B., 1999 (Dec 1). Comment on Hypselodoris maculosa from Vanuatu by Vinka Stenhouse. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/1603

Hypselodoris maculosa from Philippines

December 30, 1998
From: Erwin Koehler

Dear Bill,
This one is from a Philippines dive site called "Doljo", [Panglao Is., Philippines, Nov 1998 ]. Size smaller than 1 cm, Depth approximately 40m.
Erwin

E.Koehler@deutschepost.de

Koehler, E., 1998 (Dec 30) Hypselodoris maculosa from Philippines. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/426

Erwin,
This is Hypselodoris maculosa. It is somewhat variable in colour, especially on the rhinophores which can one, two or three red bands. ... Bill Rudman.

Rudman, W.B., 1998 (Dec 30). Comment on Hypselodoris maculosa from Philippines by Erwin Koehler. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/426

Hypselodoris from SE Sulawesi

April 22, 1998
From: Lindsay Warren

Dear Bill
Here is a Hypselodoris for you. Unfortunately I have no details as to the exact nature of the surface on which they were found but they were also part of those found in the Tukang Besi Islands in SE Sulawesi last October. Looking forward to your comments on these. The opisthobranch species count for this area is now 70 and growing.
Many thanks for your help.
All the best
Lindsay Warren

100014.2112@compuserve.com

Warren, L., 1998 (Apr 22) Hypselodoris from SE Sulawesi. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/165

This looks to be a fairly typical specimen of Hypselodoris maculosa. Up to three red bands on the rhinophores are quite characteristic. Another name that used to be given to this species is Hypselodoris decorata.

Rudman, W.B., 1998 (Apr 22). Comment on Hypselodoris from SE Sulawesi by Lindsay Warren. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/165