Known throughout the Indo-West Pacific Oceans including the central Pacific and the Red Sea.
UPPER: 22 m depth, "Sponge mound", Apra Harbour, Guam, 5 July 1988, dorsal view of 104 mm specimen (Brunckhorst, 1993: Plate 1B);
MIDDLE & LOWER: 4-10 m depth, Phi Phi Island, southern Thailand, 25 Nov. 1989, dorsal and ventral views respectively of 58 mm specimen, (Brunckhorst, 1993: Plate 1C, D).
PHOTOS: David Brunckhorst.
Notes compiled from Brunckhorst, 1993:
Large species that can be distinguished by its relatively numerous (3-6), longitudinal, tuberculate notal ridges. The ridge and bases of the tubercles are blue-grey in colour. Tubercles are capped in yellow. The foot sole possesses a black longitudinal foot stripe. The rhinophoral clavus possesses 27-30 lamellae.
Phyllidia tula has a longitudinal black stripe on its foot, but the foot is very dark grey and the notum possesses single rounded tubercles and is without ridges.
Phyllidia coelestis is a smaller species which has neither a foot stripe nor a median ridge. It is more oval in shape and possesses 19-26 lamellae on the rhinophoral clavus.
See Bohadschia graffei juvenile - a potential mimic of Phyllidia varicosa.
• Lamarck, J.B. (1801) Systeme des animaux sans vertebres. Paris.
• Brunckhorst, D.J. (1993) The systematics and phylogeny of Phyllidiid Nudibranchs (Doridoidea). Records of the Australian Museum, Supplement 16: 1-107.
Rudman, W.B., 1999 (January 12) Phyllidia varicosa Lamarck, 1801. [In] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/phylvari
April 21, 2008
From: Eddy Mannak
Here is a pictures of Phyllidia varicosa I took in August 2007 at the Wreck El Mina in Hurghada (Egypt).
Locality: Hurghada, 25 metres, Egypt, Red Sea, 29 august 2007, Wreck. Length: 10-12 cm. Photographer: Eddy Mannak.
email@example.comEddy Mannak, 2008 (Apr 21) Phyllidia varicosa from Egypt. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/20860
This is one phyllidiid which is easily identified.
March 28, 2008
From: Jean-François Hervé
Concerning message #11192:
Locality: Tépava, 14 m, Nouvelle-Calédonie, Pacific ocean, 14 october 07, sand. Length: 70 mm. Photographer: Jean-François Hervé.
Thank you for your help.
firstname.lastname@example.orgHervé, J-F., 2008 (Mar 28) Re: Phyllidia madangensis? from New Caledonia. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/21068
This is rather different from Gary Cobb's animal. I am pretty sure it is Phyllidia varicosa rather than either of the species you mention. Although the tubercles can sometimes be bluish in P. carlsonhoffi, both it and P. madangensis usually have whitish tubercles, but more importantly the tubercles in both those species are scattered and separate from one another. In your animal the tubercles are in definite rows, and some in the centre of the mantle are joined to form part of a ridge. I am sure your animal is a variety of P. varicosa in which the ridges are partially broken.
It is nice to see the photo showing part of the band of secondary gills which run along each side of the body on the underside of the mantle skirt.
March 7, 2008
From: David Abecasis
Here's a Phyllidia varicosa shot at Quirimbas archipelago, North Mozambique.
Locality: Quirimbas archipelago, 8 meters, Mozambique, Indian Ocean, 30 October 2007, Coral reef. Length: ~30 mm. Photographer: David Abecasis.
email@example.comAbecasis, D., 2008 (Mar 7) Phyllidia varicosa from Mozambique. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/21145
The western Indian Ocean used to be a region we knew very little about in terms of the nudibranch fauna, but the Forum has been very valuable in increasing the known geographic distribution of many species so I always welcome records from that part of the world.
August 22, 2007
From: Natasja Vandeperre
Here is a picture of Phyllidia varicosa from Tofo, Mozambique
Locality: Tofo, Mozambique, Indian Ocean, 19 July 2007. Photographer: Natasja Vandeperre.
firstname.lastname@example.orgVandeperre, N., 2007 (Aug 22) Phyllidia varicosa from Tofo, Mozambique. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/20495
Your records from Mozambique are very interesting, even for reasonably common species, because there are very few collecting records from this part of the southeast African coast.
July 16, 2007
From: Philibert Bidgrain
Concerning message #6687:
Reunion Island seaslugs
Alain Martinat took this photo in Rodrigues Island (near Mauritius). Before this photo I had never seen the spawn of this species except for Jeff Lockwood's photo (May 13, 2002). So do you think that this one is really a photo of Phyllidia varicosa spawn?
Locality: Rodrigues Island, Indian Ocean. Photographer: Alain Martinat.
email@example.comBidgrain, P., 2007 (Jul 16) Phyllidia varicosa spawn from rodrigues island. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/20092
Unless the photographer saw this animal laying the eggs we can't be 100% sure, but this type of egg ribbon with the ribbon attached flat on the substrate like this, rather than attached along one edge of the ribbon, is typical of the phyllidiids. It's hard to compare with Jeff's photo because we only have a view of the underside of a ribbon deposited on a smooth glass surface, but in both cases the ribbons seem to be unattached along the edges, so the ribbon in Alain Martinat's photo could well be that of P. varicosa.
March 29, 2007
From: Simon Lavers
Probably a little over excited about my first nudi photo and I thought I'd send it in. I think I still need to do a little work on it but am pleased with the basics. I haven't had chance to look it up, I know its a common one, at least I have seen it many times throughout Asia.
The camera is a Sanyo Xacti HD1a with Epoque housing, my first adventure into underwater photography and I must admit that I spent most of the time videoing the grey reef sharks. I am glad I spotted this beauty though.
Locality: Near the Blue Corner, 20 m, Palau, Pacific, 15 March 2007, Second dive of the day. Length: 5 cm. Photographer: Simon Lavers.
firstname.lastname@example.orgLavers, S.J.H, 2007 (Mar 29) My first nudi photo. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/19756
You are allowed to be excited with your first nudibranch photo. I hope it whets your appetite to take many more. Your animal is Phyllidia varicosa. Phyllidia and its relatives all have particularly distasteful chemicals in their skins, which seems to protect them from inquisitive and hungry fish. That is probably why they seem to find it safe to wander around openly during the day, and are often the most commonly seen nudibranchs seen during day diving.
September 5, 2006
From: Andrew Trevor-Jones
I took this photograph at Challenger Bay on Ribbon Reef #10 on the Great Barrier Reef
I think it might be Phyllidia coelestis.
Locality: Challenger Bay, Ribbon Reef #10, Great Barrier Reef, 7.3 metres, Queensland, Australia, Pacific Ocean, 20 August 2006, Sandy with coral boulders. Length: ~ 3 cm. Photographer: Andrew Trevor-Jones
email@example.comTrevor-Jones, A, 2006 (Sep 5) Phyllidia varicosa from the Great Barrier Reef. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/17704
It certainly seems to have quite a bit of black on the mantle, like some P. coelestis, but in that species there is a central black band with a ridge on each side of the midline. In your animal we have the opposite with a ridge in the midline, which would make it Phyllidia varicosa.
September 12, 2005
From: Kamal El Tawil
Here are some pictures of Phyllidia varicosa I have taken in June at St. John's reef.
Locality: Small Reef, St. John's Reef, near Ras Banas, sthn Egypt. Red Sea. Depth: 8 metres. Length: approx 4 cms. 27 June 2005. Photographer: Kamal el Tawil
El Tawil, K., 2005 (Sep 12) Phyllidia varicosa from southern Egypt. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/14690
May 27, 2005
From: Charles Rowe
Here is one from Kalifushivaru, Kuredu, Maldives 23 April 2005. 19 metres. I'm not what it is
Charles.firstname.lastname@example.orgRowe, C., 2005 (May 27) Phyllidia varicosa from the Maldives. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/13870
It's Phyllidia varicosa.
March 16, 2005
From: Alyson Browett
I learned about nudibranchs from a couple I met on my way home from Costa Rica in 2002 -- too late to search for them while diving.
However, while in Koh Tao, Thailand, in mid-July 2004, I spotted two at about 10-15 meters depth. Koh Tao is in the Gulf of Thailand, and we were about 200 meters from shore. My husband, trying out underwater photography for the first time, got a minimally recognizable shot (attached).
I began calling them fried egg nudibranchs without knowing anything about them. I just came across your site while searching for information on nudibranchs, and I have to say that this is one of the best sites on the Web (and I design information Web sites for a living).
Locality: Koh Tao, Thailand, Gulf of Thailand. Depth: 10-15 meters. Length: large: 6 in. small: 3 in. 21 July 2004 reef. Photographer: John Ralph
I'm interested in knowing any more information about my fried egg nudibranchs!
Purcellville, VA, USA
email@example.comBrowett, A.M., 2005 (Mar 16) Thai fried egg nudibranch?. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/13341
Your two animals are phyllidiid nudibranchs - and both have a 'fried egg' colour pattern.. The larger is Phyllidia varicosa and the smaller one is, I think, Fryeria menindie. You can find more about the individual species on their respective Fact Sheets and accompanying messages. One interesting point your photo illustrates is that during the day, the phyllidiids are almost the only sea slugs which show themselves out on the reef. They are well protected from possible fish attack by very noxious chemicals they store in small glands in their skin, which they obtain from the sponges they feed on. There is a whole field of natural products chemistry which has built up to study the way animals have evolved the ability to make defensive chemicals and for others to steal them for re-use. The impetus for the research is not so much because of an seoteric interest in this field of evolution, but because these powerful molecules may turn out to cure some nasty human ailment.
Glad you like the site. We are in the middle of an upgrade at the moment - hopefully when I get some time I will put in some guides to make it easier for novices to do some self identification - or at least get down to a family grouping.
February 6, 2004
From: Charles Rowe
Here is another nudis which I photographed in January at Sodwana in Kwa Zulu Natal, South Africa.
Sodwana - 7 Mile Reef 4 January 2004
firstname.lastname@example.orgRowe, C., 2004 (Feb 6) Phyllidia varicosa from Sth Africa. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/12131
This is Phyllidia varicosa.
December 12, 2003
From: Terry Moore
I purchased this today and want to know what it is before I place in tank ... I was out of town when I purchased or would have asked first .. It was on the glass like a nudi but larger that any I have seen. It was about 3in long and 3/4in in dia.
email@example.comMoore, T., 2003 (Dec 12) Slug id and is it reef safe.. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/11674
I have difficulty with the way many aquariists work. I would have thought the first step would be to find out about animals you plan to introduce into your aquarium before you buy them. This is definitely a case in point. It is Phyllidia varicosa, and belongs to a family of nudibranch which are not a good idea to keep in aquaria as they produce nasty secretions which can kill everything in a tank. Have a look at an earlier message on the topic.
You ask is it 'reef safe'. In 'reef aquariums' it is not a safe addition, but it is perfectly safe when its left where it should be - on a natural tropical reef. Unfortunately natural tropical reefs are becoming endangered habitats because of the desire for people in temperate climates to have 'reef' aquariums. We live in a strange world.
October 12, 2003
From: Asther M. Lau
Attached is a common slug found in Malaysian waters. As I scanned through your species list, I realised this 'hard-type' has a long list of different species! Would appreciate if you can help identify this one.
Site: Tjg Gemuk, Tenggol Is. Malaysia
Depth: 15 meter
Size: Approx. 6 - 8 cm
Date: 31st May 2003
Asther M. Lau
firstname.lastname@example.orgLau, A.M., 2003 (Oct 12) Phyllidia varicosa from Malaysia. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/11199
When you describe this as a 'hard type' I am not sure if you are describing how it feels to touch or how difficult it is to identify.
This is Phyllidia varicosa. I have included a close-up alongside to show a couple of interesting features visible in your photo. I have put a red ring around the anal papilla which is usually quite difficult to see in photos. In most dorids there is a dorsal circle of gills with the anus opening in the centre. In the phyllidiids, the circle of gills is lost, but in most cases the anus, stays in the dorsal midline, marking the spot where the gills used to be. The other feature you can see are the white specks all over the mantle. These are glands which can secrete a very toxic white secretion when the animals are disturbed. These secretions can quickly kill a tank of fish - another good reason to leave nudibranchs in the sea
March 24, 2003
From: Mary Jane Adams
Phyllidia varicosa is as common in the Andaman Sea as in other places I have dived in the Western Pacific. Most of them were unremarkable, however this one has just a hint of pale yellow in the pustules and rhinophores. Do you think it is an unusual color form of P. varicosa or something else?
Length: about 3cm
Depth: about 15 meters
Divesite: Western Rocky, southern Myanmar, Feb. 25, 2003.
email@example.comAdams, M.J., 2003 (Mar 24) White Phyllidia varicosa? from Burma. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/9397
Dear Mary Jane,
No more species of Phyllidia please! No this is just a very pale form of Phyllidia varicosa. I guess the 'make yellow' gene is switched off or inhibited in this animal.
March 24, 2003
From: Mary Jane Adams
Of all the hundreds of Phyllidia varicosa I have seen around the world, this is the first time I have seen them mating and I have yet to see any laying eggs. Since these slugs are so common and widespread, it seems like I should be seeing reproductive activity more often. Do you have any ideas about this? Does anyone have a picture of P. varicosa laying eggs? I shot this picture at 16 meters at Three
Islets, Andaman Sea, Myanmar, Feb. 14, 2003.
Mary Jane Adams
firstname.lastname@example.orgAdams, M.J., 2003 (Mar 24) Phyllidia varicosa mating. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/9399
Congratulations Mary Jane,
Photos and observations of any phyllidid mating or egg-laying, are indeed very rare. We have photos on the Forum of Phyllidiella pustulosa mating and laying eggs, and a tantalising photo of Phyllidia babai and P. ocellata mating together. Other photos would be very welcome.
I have no idea why so few mating observations have been made despite their relative abundance. We tend to think that most nudibranchs mate whenever they meet because they are relatively rare, or hide a lot, and so it is worth taking advantage of every meeting. Perhaps the converse is true as well. When you are relatively common and so are likely to come in contact with potential mating partners regularly, perhaps there is no great advantage in mating at every meeting?
March 13, 2003
From: Rudolph van Jaarsveld
Please assist in the identification of this.
Photo taken at Ponta do Ouro in southern Mozambique, 15 meter depth, 20 February 2003.
Rudolph van Jaarsveld
email@example.com Jaarsveld, R., 2003 (Mar 13) Phyllidia varicosa from Mozambique. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/9293
This is Phyllidia varicosa
November 25, 2002
From: Paul Young
Here is one of the nudibranchs that Charlotte and I found at Pemba Island, off the coast of Tanzania, western Indian Ocean, in November/December 2001. This species was photographed on the 29 November, on the east side of Pemba
firstname.lastname@example.orgYoung, P., 2002 (Nov 25) Phyllidia varicosa from Pemba. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/8429
I am pretty sure this is a juvenile of Phyllidia varicosa. I assume the yellow capped longitudinal ridges down the back are still developing.
July 17, 2002
From: Maliza Anuar
Photo from Tioman Island, off the east coast of west Malaysia. Dive Site: Soyak Island, 23 July 2002, 4pm. Depth: 13-15m. Size: 4cm
I see loads of these guys when diving around Tioman and also loads without the yellow tips. Are those without the yellow tips the same species?
email@example.comAnuar, M., 2002 (Jul 17) Phyllidia varicosa from Tioman, Malaysia. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/7475
This is Phyllidia varicosa. If you go to the Species List you will see a frighteningly long list of species under the Family Phyllidiidae. I wish we could say that those with yellow tips were one species and those without were another but I am afraid their are many species which only differ from others in the most subtle differences in colour pattern or tubercle arrangement. The reason you see so many around is that they have glands in their skin which produce distasteful and poisonous secretions, so they are to some extent protected from the attentions of hungry fish, even in daylight.
June 28, 2002
From: Valda Fraser
In South Africa Phyllidia varicosa can grow huge. This one is at least 120mm.
Locality: Park Rynie, south coast KwaZulu-Natal, South Africa, 30m
Date: June 2002
Hope you are impressed!
firstname.lastname@example.orgFraser, V., 2002 (Jun 28) Giant size Phyllidia varicosa. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/7376
I'm very impressed. I've seem them about 90mm long, but 120mm is certainly large
June 24, 2002
From: Kheong Sann Chan
Here are some more photos from Pulau Dayang off the east coast of west Malaysia.
Location: Pulau Dayang, Pulau Lang
Date: 8 June, 2100
Depth: 15+ m
Kheong Sann Chan
email@example.comChan, K.S., 2002 (Jun 24) Phyllidia varicosa from west Malaysia. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/7226
This is Phyllidia varicosa
May 13, 2002
From: Jeff Lockwood
Thanks for your reply - all I can say is that they shouldn't be selling these creatures if they don't know how to help them survive. I'm going to pay another visit to the store which sold me my Phyllidia varicosa and give them a little piece of my mind, the guy there told me he was a filter feeder, and I really didn't believe him so I checked on it. Well all I can say is thanks, I know you probably hear that a lot, but I sincerely mean it. I know that you must be really busy and that you really didn't even have time for me, but you made time when most people wouldn't have. So, all I can say is that you are going above and beyond your call of duty and people are noticing. If there were more peope like you in the world, everything would be going a lot smoother. I cannot believe that you got back to me within a day. My brother is a biology major, and he had a lot of experience with zoology and nobody ever e-mailed him back when he had questions like I asked you, so you are making a difference and there needs to be more people like you out there, wanting to help.
So here are the pictures I said I would take of the slug, and 1 of the egg rings (Now you cannot see the whole egg ring but know that they are almost 4 perfect circles, and I also made the mistake of touching the eggs and they are a hard sort of mucus)
well, thanks again...
firstname.lastname@example.orgLockwood, J., 2002 (May 13) Photos of Phyllidia varicosa in aquarium. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/6687
Thanks for the photos. The only thing your aquarium store person got right was the name of the slug. Looking at the egg ribbon photo I suspect the slug has laid a ribbon without proper eggs in it. Often when stressed they can lay an egg ribbon without eggs, or sometimes with no eggs but a long irregular string of yolky material. Hopefully, as more customers like you let the aquarium trade now they are not happy with the misinformation that is being dished out about nudibranchs, the trade will stop stocking them.
May 11, 2002
From: Jeff Lockwood
Ok, now it seems I have a problem.
1st a few questions, the guy at the shop sold me a Phyllidia varicosa (my mistake not reading up first). He told me that this was not a nudibranch, but a sea cucumber... is this correct? I looked it up and it says that it is a rough-nobbed sea slug, and I know its Phyllidia varicosa. This same guy also told me that this species did not eat anything in particular but would feed off the particles floating around in the water. I did not belive this because of way these things are built, it looks like they crawl on something and eat it, not catch it out of the air, so a looked here and it seems that these guys eat sponges. So with that, I was wondering if there was a particular sponge this guy would like to munch on? Now I read many other question, and I know that people ask this question over and over again, so I didn't want to waste your time so I looked up "feeding" but I found nothing for this particular guy. The reason I ask is because I have a brown sponge (which I don't know the type) on a rock in my tank and I would be glad to give it up to the slug for food(its not as pretty) but I didn't know if he would like it, so my question is should I bother the little guy and actually place him on the sponge?
Now, why I am worried is because for the last week he has spent at the top of the tank, and he also just laid a 4 ringed, perfect spiral batch of eggs, and you said earlier that this could be a last attempt to keep his species going or something. These eggs might actually be fertile because it was sitting right next to another one in the tank when I got it. So to make it short and sweet:
Is it a nudibranch or sea cucumber?
Is there any sponge you can recommend that I get it for food?
Should I place it on my brown sponge?
Is there any way you would recommend me roping or closing off the eggs from other fish and the filter/powerheads?
and also Would you like a picture of the egg spiral or the slug? it seemed like you liked pictures, you have quite a bit.
Well, thank you for your time and I am sorry for taking so much of it as I am sure you have answered these questions many of times, but you seemed quite knowledgeable and I don't want to lose my little guy so I had too.
Thank you very much...
email@example.comLockwood, J., 2002 (May 11) Phyllidia varicosa, dying?. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/6625
I would very much like a photo of the animal and its egg ribbon. We know so little about these animals that a photo of an animal with its egg ribbon would be quite a useful piece of information - and would mean it life was worthwhile - if rather abbreviated.
There is no harm in seeing if it will eat your brown sponge but I doubt it. One thing to be careful of with phyllidias in aquaria is that they can exude nasty poisons which kill fish and other life in aquaria. I suspect if it hasn't already done so it is unlikely to at this stage - probably no energy left to produce the chemicals. Concerning the eggs. They may hatch into microscopic free-swimming larvae but they feed on microscopic algae (phytoplankton) which I am sure you won't have in your aquarium so will almost certainly die. Even if you did successfully keep the larvae alive, they need their adult food sponge to trigger their change from larvae to crawling slugs so again not much joy.
Concerning your other questions. They are not Sea Cucumbers although there is a message on the Forum with a photo of one juvenile sea cucumber which mimicks the shape and colour of Phyllidia varicosa.
April 21, 2002
From: Kheong Sann Chan
Hi Dr. Rudman,
Hers is another nudibranch from Pulau Dayang off the East Coast of Malaysia which I photographed on 14 April, 2002. Depth varied approximately 15-23m deep.
firstname.lastname@example.orgSann Chan, K., 2002 (Apr 21) Phyllidia varicosa from Malaysia. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/6770
This is Phyllidia varicosa, which is a common nudibranch throughout the whole of the Indo-West Pacific.
October 11, 2001
From: Des Paroz
Following my other message on a species that I guessed as being Phyllidia coelestis, attached is a photo of a critter I deduce must be P. varicosa. It seems to have the tell tale light blue/grey ridge down the centre-line.
This was taken at a site off Tufi, PNG, called Goby's Cave, in the Five Star Reef. Depth was about 22m, and water temp about 27C.
email@example.comParoz, D., 2001 (Oct 11) So this must by Phyllidia varicosa!. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/5429
Yes this is P. varicosa. I have included an enlargement of the back end of your animal because it shows the anal papilla very well. Most dorids have a circlet of gills around the anus. However in phyllidiids, the dorsal gills are replaced by a set of gills which are found in the groove between the mantle and the foot [see nudibranch gills page]. Often the anus pore, and the papilla which extends out of it, are not visible in photos, and not easily seen if the animal is disturbed. This can be a problem, because the genus Fryeria, which differs from other phyllidiids in having its anus opening beneath the mantle skirt, has much the same shape, size and colour as these blue and yellow species of Phyllidia. So unless you know where the anus opens you can have a problem.
September 3, 2001
From: Mary Jane Adams
This a Phyllidia varicosa photo, just for laughs. No, I didn't plant the slug on the crocodile fish; I found it this way. I don't think it is a significant association. The slug has just blundered into and over an ambush hunter who is not the least bit disturbed by it.
Komodo Island, Indonesia,
Aug. 4, 2001.
firstname.lastname@example.orgAdams, M.J., 2001 (Sep 3) Phyllidia varicosa on crocodile fish. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/5189
Dear Mary Jane,
There is something incongruous about a slug moving faster than a fish. Even though the colours are a pretty good match, I agree that only the most foolhardy would propose a symbiotic relationship.
April 12, 2001
From: Kirk Gibson
Here is another nudibranch from Exmouth, northern Western Australia.
email@example.comGibson, K., 2001 (Apr 12) Phyllidia varicosa from Exmouth, W.A.. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/4108
This is Phyllidia varicosa, which is found quite commonly right throughout the tropical Indian and western Pacific Oceans.
January 26, 2001
From: Leif Abrell
Here is a photo of Phyllidia varicosa which I took in NW Madagascar in April, 2000.
Photos of the other opisthobranchs from Madagascar can be seen at http://www.columbia.edu/~la202/Mad-opisth2000.html
firstname.lastname@example.orgAbrell, L., 2001 (Jan 26) Phyllidia varicosa from Madagascar. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/3573
January 10, 2001
From: Dave Harasti
Is this nudibranch Phyllidia alyta or P. varicosa?? It was found off Koh Tao Island in Thailand (late October 2000) and it was very very common, it could be found everywhere at various depths from 1 to 20 metres.
Harasti, D., 2001 (Jan 10) Phyllidia varicosa? from Thailand. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/3368
I'm afraid it is not always easy to identify these animals from one dorsal photo. Often two or three very similarly coloured species will occur at the same locality and it is only by having information on other characters, such as the median black line on the sole of the foot, which occurs in some species of Phyllidia, that an attempt at identifications can be made. In this case I really would need to know where the anus was. One genus, Fryeria, is characterised by having the anus opening in the posterior midline below the mantle skirt, and it is possible that some of these are a species of Fryeria.
So with that proviso here are my guesses:
TOP RIGHT: They are both probably Phyllidia varicosa but the upper animal has all the tubercles separated which is not usual in P. varicosa.
LOWER PHOTOS: These are probably both Fryeria marindica but it is possible that the LOWER RIGHT animal is Phyllidia elegans.
Sorry I can't be more definitive but I sometimes have problems with these when I have the live animal in my hand.
January 5, 2001
From: Mary Jane Adams
I found this nudibranch in the Florida Group of the Solomon Islands on a divesite known as Twin Tunnels. This is a mixed hard and soft coral covered pinnacle that arises from deep water to about 15 meters on top. The two tunnels begin on top of the reef and open out on a vertical wall at 31 meters. This phyllidiid was sitting on a sponge inside one of the tunnels at 28 meters. The mantle is light blue. With my 8x loupe the blue appears to be closely arranged speckles. The mantle has three ridges which join near the caudal end. There are rounded white tubercles on the the ridges as well as laterally on the mantle. Black lines divide the ridges and form some branches which extend toward the edge of the mantle. There are additional black lines between the lateral tubercles. A narrow white band surrounds the edge of the mantle. The rhinophores are light yellow. I did not find a picture of a phyllidiid like this in any of my books. The closest one I found was the image Phyllidiopsis sphingis on your website.
Length: about 35 mm
Water temp: 84 F
November 17, 2000
Can you ID this one?
email@example.comAdams, M.J., 2001 (Jan 5) Unknown Phyllidiid from Solomon Ids. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/3427
Dear Mary Jane,
I am pretty sure that this is just a pale animal of Phyllidia varicosa. If you brightened the pale areas up with a bit of yellow you would have a perfectly respectable Phyllidia varicosa. I sometimes come across these 'washed-out' animals. It just seems to be a lack of yellow pigment.
December 23, 2000
This is my main object for studying chemical ecology of prey-predator relationship between nudibranch and sponge. This species (Phyllidia varicosa) is not so abundant in the area of Karang Lebar Atoll, Thousand Islands, Indonesia. But I found easily this species in Pramuka Islands, Thousand Islands Indonesia.
firstname.lastname@example.orgYasman, Y., 2000 (Dec 23) Phyllidia varicosa from Indonesia. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/3332
I look forward to seeing the results of your study.
September 23, 2000
From: Christopher Shaw
Before reading your Forum I purchased a sea slug of the Phyllidia varicosa species. 'Scrambled egg nudibranch' it was called. I have had it for a few weeks and it seems to be doing well. Tonight, I noticed it laying what I think are eggs in a spiral shape on the glass on the top of the tank. I was wondering if there was any chance of the eggs actually hatching and perhaps some growing to adulthood. That's if they don't get sucked into the filter or protein skimmer at some point.
I was also wondering if it would be possible to isolate the egg masses in a jar with a air stone? Any thoughts on this.
email@example.comShaw, C., 2000 (Sep 23) Phyllidia varicosa in an aquarium. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/3051
If you don't have the sponge it feeds on in your aquarium then I am afraid it will be slowly starving. This may take a month or two because starving nudibranchs slowly start absorbing 'excess' organs such as their reproductive system, in an attempt to stay alive. It sounds like your animal has laid an egg ribbon. This could mean that it mated before it was caught, or perhaps in the shop, if they had more than one, before you bought it. There is also the possibiity the eggs are infertile. Often distressed animals will lay an egg-ribbon and shortly after die as though this is their last attempt at keeping the species alive. Often the eggs are infertile.
I'm afraid that even if the eggs are fertile I can't really give you good news. If they develop they will reach a stage where the larvae will hatch out as little swimming veliger larvae. [If you use the SEARCH button you will find some photos of veligers]. In the case of P. varicosa I am pretty sure its veligers spend some time swimming in the plankton, feeding on microscopic algae. Unless you have phytoplankton cultures to feed them I am afraid the larvae will die of starvation. There is also a chance they will be caught by your skimmers and if you transfer them to a jar they will probably be trapped in the surface film.
Sorry again for not having any good news
July 27, 2000
Would you mind telling me please some literatures about the ecology of Phyllidia varicosa?
Thanks a lot.
student of ISATEC
Univ. of Bremen
firstname.lastname@example.orgYasman, 2000 (Jul 27) Ecology of Phyllidia varicosa. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/2233
Although there are various notes on feeding observations and associations with particular sponges, I can't recall any published reports on the ecology of any species of the Phyllidiidae. Hopefully someone will prove me wrong and let us know of some.
March 24, 2000
From: Valda Fraser
Please confirm that this nudibranch is Phyllidia varicosa.
Localtiy: South Coast KwaZulu- Natal, SOUTH AFRICA. Park Rynie - 25m
Date: November 1999
email@example.comFraser, V., 2000 (Mar 24) Phyllidia varicosa from South Africa. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/2118
Yes it looks like P. varicosa to me. The orange sponge looks like a potential food, so keep a watch out for signs of 'nibbling' if you see them close together.
January 23, 2000
From: Bill Rudman.
As promised I have had a closer look at the photo Bob Bolland sent when I was away. I am pretty sure it is a pale form of Phyllidia varicosa in which the yellow, faintly visible on the upper half of the rhinophores, is absent on the tubercles.
January 8, 2000
From: Robert F. Bolland
In going through some of my Okinawan phyllidiid slides I came across the enclosed JPEG. The all-white rhinophores are unlike anything I've seen before. Any ideas as to what this may be?
RFB # 3119
Odo Village Dive Site, Okinawa, 30 Jan 1993
I trust the New Zealand holiday is going well . . . I understand you have "World Class" fishing there.
firstname.lastname@example.orgBolland, R.F., 2000 (Jan 8) Okinawa Phyllidiid. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/1733
I think this is a Phyllidia - the white rhinophores are probably a very pale yellow, though I will check it out when I get back to Sydney.
New Zealand's a great place, great fishing, great wine, friendly people etc etc. I'm 'house-sitting' on Auckland harbour and watch the America's Cup yachts go out each day, even looked for some nudibranchs yesterday .. generally having a great time.
See message added Jan 21
October 3, 1999
From: Erwin Koehler
Here are some photos of Phyllidia varicosa from the wreck of the "Liberty", depth 18 m, in Bali, Indonesia, March 1997 (photos by H.-H. Harms).
Do you know what is at its head? A parasite?
Medslugs.Koehler@t-online.deKoehler, E., 1999 (Oct 3) Parasite? on Phyllidia. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/1392
It is possibly parasite, though I have never seen one remotely resembling this, or it is possibly some internal glands which have burst through the body wall following damage.
You'll note that the head region looks quite abnormal, rough, but without the normal ridges and tubercles. One characteristic feature of Phyllidia are the rhinotubercles, a pair of tubercles found, one behind each rhinophore pocket. These are absent in this specimen. I suspect something has taken a bite out of its head, which has partially grown back. It is possible the white fan-like structure are oral glands, normally found around the posterior part of the pharnyx or buccal bulb, which have burst out through a weakness in the damaged body wall ..... but this is only a guess on my part, if someone else has a more convincing explanation please let us know.
January 4, 1999
From: Rob See
I am an aquarist in Brisbane, who has just recently caught an interesting nudibranch in Pumicestone passage, off Golden Beach, Caloundra. I am really quite taken with these animals, and have been surfing the net for information on the little critters. Recently I saw a page that told me that nudibranchs do not live very long in aquariums, since they have a highly specialized diet. This has caused me some concern, not only because of my new friend, but also because today I forked out $18.95 for a Phyllidia varicosa. Could someone please clarify this for me as I am somewhat worried
Thanks in advance
email@example.comSee, R., 1999 (Jan 4) Can I keep phyllidiids in the aquarium?. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/433
Yes you are right about nudibranchs having very specific diets. Often you need to know the exact species they feed on - a close relative may not do. Often they will survive in aquaria for some weeks without food but it's probably not a very happy life for them. There are keen aquarists, who are also divers, who try and find what their nudibranchs eat and try and keep a supply of the food alive in their aquarium as well. This may require regular replacement of the food for often it (sponge, hydroid etc) is as difficult to keep alive as the nudibranch. If you know what nudibranch you have we may be able identify its food for you.
The short answer to your second question about keeping Phyllidia varicosa in aquaria is DON'T!
All phylliids protect themselves by taking chemicals from the sponges they feed on and refine them into particularly nasty terpene molecules with attached isonitriles. You don't need to know the chemical details but I have opened a door into a room in which I have kept phyllidiids overnight to be met by an acrid eye-watering atmosphere filling the room. Keeping phyllidiids in aquaria is a pretty sure way of killing other things in your tank within a short period. Experiments with P. varicosa have shown that, when disturbed, they secrete a poisonous mucus capable of killing fish and crustaceans in an aquarium (Johannes, 1963). Gunthorpe & Cameron (1987) also described the toxic qualities of three Phyllidia species (P. elegans, P. nobilis and P. ocellata) from Queensland waters.
Have a look at the pages on the Forum where various aspects of nudibranch biology are discussed, in particular those dealing with colour and defence, including Defensive mucus, mimicry and Phyllidiella pustulosa. Phyllidiids are one of the few groups of nudibranchs that are commonly seen during daylight hours. We now know that they are safe from fish predation because of the distasteful chemicals they secrete through their skin.
Gunthorpe, L. & A.M. Cameron, 1987. Bioactive properties of extracts from Australian dorid nudibranchs. Marine Biology, 94: 39-43.
Johannes, R.E., 1963. A poison-secreting nudibranch (Mollusca: Opisthobranchia). The Veliger, 5(3): 104-105.
Bill Rudman.Rudman, W.B., 1999 (Jan 4). Comment on Can I keep phyllidiids in the aquarium? by Rob See. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/433