Glaucus atlanticus
Forster, 1777

Order: NUDIBRANCHIA
Suborder: AEOLIDINA
Family: Glaucidae

DISTRIBUTION

Circumglobal in temperate and tropical waters.

PHOTO

UPPER: Collaroy Beach, Sydney, February 1987. 4cm long alive. Photographed from above to show the modified foot. Note: as these animals float upside down, their foot is always dorsal. LOWER: Feeding on the "Portuguese man-of-war" or "Bluebottle", Physalia.
PHOTOS: Bill Rudman.

RELATED TOPIC

Glaucilla marginata

Glaucus atlanticus and its close relative, Glaucilla marginata, live in close association with what Sir Alistair Hardy described many years ago as "The Blue Fleet" - the siphonophores such as Physalia, Velella, Porpita and the other associated animals including the "Violet snails" of the genus Janthina. All these animals float on the surface of the ocean being carried by the currents and the winds. Most of us are only aware of their existence when days of onshore winds blow great fleets of them on to the beaches, causing pain and angst for swimmers.

Both species spend their life floating upside down in the water, partially bouyed by a gas bubble in their stomachs.

The two nudibranchs feed almost exclusively on Physalia, and as Tom Thompson and Isobel Bennett reported some years ago, it appears that they are able to select the most venomous of Physalia's stinging nematocysts for their own use. Like most aeolids, they store the nematocysts in special sacs (cnidosacs) at the tip of their cerata .

There are a number of reports in Australia of kids engaged in "Bluebottle" fights - where they throw stranded Physalia at each other - being badly stung by inadvertently playing with Glaucus and Glaucilla, both of which, by concentrating the most venomous of Physalia's nematocysts, are much more deadly.

Another interesting feature of the two species is their colouration. They both exhibit a textbook example of colour countershading. Their foot and undersides of the cerata, (which because they float upside down is effectively their dorsal surface), is blue or blue and white which helps to camouflage them from predation (sea birds) from above. Their true dorsal surface, which faces down in the water, is silvery grey to effectively camouflage them from fish looking up from below.

See photos of pelagic egg strings.

References:
• Bergh, L.S.R. (1884) Report on the Nudibranchiata dredged by H.M.S. Challenger during the years 1873-1876. Report of the Scientific Results of the Voyage of H.M.S. Challenger during the years 1873-76, ... Zoology, 10(26): 1-154, pls. 1-14. [Glaucus: p.10-16]
• Forster, G. (1777) A voyage round the world in His Britannic Majesty's sloop, Resolution, commanded by Capt. James Cook, during the years 1772, 3, 4, and 5 by George Forster. Vol 1: p49.
• Thompson, T.E. & McFarlane, I.D., 1967. Observations on a collection of Glaucus from the Gulf of Aden with a critical review of published records of Glaucidae (Gastropoda, Opisthobranchia). Proceedings of of the Linnean Society, 178: 10-123.
• Thompson,TE. & Bennett,I., 1969. Physalia nematocysts: Utilised by mollusks for defense. Science, 166: 1532-1533.
• Thompson,TE. & Bennett,I., 1970. Observations on Australian Glaucidae (Mollusca: Opisthobranchia). Zoological Journal of the Linnean Society, 49: 187-197.

Authorship details
Rudman, W.B., 1998 (November 6) Glaucus atlanticus Forster, 1777. [In] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/glauatla

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Related messages

Glaucus from South Africa

May 3, 2010
From: Emil H Niksch

Weird Creature found on the beach in South Africa

Locality: Buffalo Bay, 0 feet, South Africa, Indian, 2 May 2010, on sandy beach at low tide. Length: 2 inches. Photographer: Emil H Niksch.

Emil H Niksch

ecoafrika@gmail.com

Niksch, E. H., 2010 (May 3) Glaucus from South Africa. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/23604

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Glaucus atlanticus from Florida

April 30, 2010
From: Stephanie Armentrout

Concerning message #19205:

hey there, i'm not sure of the species, but we found a couple of the exact ones on miami beach, fl. US this past weekend. they were floating near the seaweed.

Locality: Miami beach, on shore, Florida, US, atlantic, april 24th, 2010. Length: 1". Photographer: Stephanie Armentrout.

Stephanie Armentrout

sdotdesign@gmail.com

Armentrout, S., 2010 (Apr 30) Glaucus atlanticus from Florida. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/23577

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Glaucus atlanticus from nthn New South Wales

April 23, 2010
From: Jayson Dyer

Trying to found out what this is

Locality: Byron bay, washed onshore, N.S.W, 2 feb 2010, beach. Length: 17 mm. Photographer: steff.

Jayson Dyer

kjkj666@hotmail.com

Dyer, J., 2010 (Apr 23) Glaucus atlanticus from nthn New South Wales. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/23552

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Re: Glaucus atlanticus from Florida

April 6, 2010
From: Douglas Hernandez

Concerning message #23434:

Dear Mr. Bill we saw this Glaucus atlanticus in color white and blue on Hollywood Beach, Florida last Saturday May 3, floating on the shore.

I have a question, My son get a pain and rash like a Jellyfish burn on his leg on this day, but we saw the Glaucus later on this day and now I not sure if that rash inside my son's swimming shorts was caused by the Glaucus.

If this a poison? Because I find inside my son's underwear some little things like that (Glaucus).

Appreciate your comments
Douglas

douglas@dgsmiami.net

Hernandez, D., 2010 (Apr 6) Re: Glaucus atlanticus from Florida. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/23444

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Glaucus atlanticus from Florida

April 5, 2010
From: Emma C.

Concerning message #19551:

Today me and my friends and family were at the Key Biscayne beach in Miami Florida. We saw one of those 3 and we were trying to find out what it was we got pictures and thought it was a new species. Does it relate to anything??? It was low tide. How does it get from Mexico to Miami?

Locality: Miami , 3 inches, Florida, Atlantic, 02 April 2010, Low tide , no waves very calm near seaweed. Length: 4 centimeters. Photographer: my dad.

Emma C.

salomeb@msn.com

Emma C., 2010 (Apr 5) Glaucus atlanticus from Florida. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/23434

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Blue Bottles and Nudibranch washed up at Kiama, NSW

March 24, 2010
From: Cherie Noon

This Nudibranch was found at Kiama, East Van Park, East Beach. It was a windy and rainy day, The beach had washed up Blue bottles every where. I was showing my daughter the blue bottles and we found the Nudibranch on the sand. After taking photos we put it back into the water, hopefully it survived.

Locality: East Beach Kiama, NSW, Australia, South Pacific Ocean/Tasman Sea, Feburary 2009, Sandy Beach. Length: 30mm. Photographer: Cherie Noon.

Cherie Noon

cherienoon@bigpond.com

Noon, C.L., 2010 (Mar 24) Blue Bottles and Nudibranch washed up at Kiama, NSW. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/23389

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Glaucus atlanticus in Hawaii

January 29, 2010
From: Aaron Silva

I spotted a Glaucus atlanticus on Waimanalo Beach on Oahu. It was at 9;30 a.m. January 20, 2010. I'm not sure how common they are in Hawaii, but I have lived here all my life and have never seen one before. There were also many large Portuguese Man O War on the beach.

Locality: Waimanalo Beach, On the beach. , Hawaii, U.S.A, Pacific, 20 January 2010, Wet Sand. Length: 3/4 of an inch

Aaron Silva

emunesystem@yahoo.com

Silva, A., 2010 (Jan 29) Glaucus atlanticus in Hawaii. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/23136

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Glaucus atlanticus find in Northern NSW Australia

January 20, 2010
From: Matthew Ross

Just before Christmas last year we had onshore winds blowing all day and it was overcast. So we decided to go for a walk down the beach with the kids.
My Wife, as always, had her camera on hand and took photo's of these beautiful creatures that had washed up with the Velella Vellela, blue bottles and small jellyfish.

When we placed the Glaucus in the water upside down they would slowly flip themselves over. When they were on the sand they were compact and closed in as if trying to keep warm. It was amazing to watch them open up every time we put them in the water.

We have many more photo's if you wish to see more.

Locality: Minnie Waters main beach North end near headland. East of Grafton, on shore, NSW Australia, Pacific, 21 December 2009, sandy beach onshore winds. Length: 10mm to 20mm. Photographer: Fiona Ross.

Matthew Ross

mattyross46@hotmail.com

Ross, M.V., 2010 (Jan 20) Glaucus atlanticus find in Northern NSW Australia. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/23104

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Glaucus atlanticus from Hawaii

September 8, 2009
From: Enjoli' Hoskins

Concerning message #1814:

Hi

I live on the island of Kauai (Hawai'i) and yesterday my children and I found this beautiful creature. Intrigued we looked online to learn more about the creature and located this site. Now we know the creature as Glaucilla marginata (a remarkably beautiful sea slug).

Locality: Nukuli'i, 1-2 feet, HI, USA, Pacific Ocean, 04 September 2009, rough; choppy. Length: 1 in. Photographer: Jeff .

Enjoli' Hoskins

enjoli@hawaii.edu

Hoskins, E.K., 2009 (Sep 8) Glaucus atlanticus from Hawaii. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/22654

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Occurrence of albino Glaucus atlanticus?

August 31, 2009
From: Evan Orellana

Greetings,

 I work over at a nature center in southeast Florida doing research on cnidarian nematocysts. One day we collected several Glaucus from the shore and found one lacking pigment. I kept it for several weeks and got some photos. is this common? or has ever been recorded so far?

Locality: Boca Raton , 0ft. at shore, Florida, USA, Atlantic Ocean, 21 February 2009, strong ofshore winds, current northern. Length: 16 mm. Photographer: Kim Mohlenhoff.

Evan Orellana

e_orellan@hotmail.com

Orellana, E.R., 2009 (Aug 31) Occurrence of albino Glaucus atlanticus?. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/22627

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Glaucus atlanticus from Pacific coast of Panama

May 14, 2009
From: Clark Misner

Concerning message #16534:

I found a batch of these little guys on the Pacific side of Panama. These are black though.

To me they look like live tattoos. I suppose that since they eat Man-o-wars they wouldn't be a good candidate for an aquarium.

Sorry about the quality of the photos. I never really thought I would be taking shots of such little critters.

Locality: Playa Uverito, on the beach, Panama, Pacific Ocean, 09 April 2009, Washed up on the beach. Length: 1.5 inches. Photographer: Clark Misner.

Clark Misner

clarkmisner@yahoo.com

Misner, C., 2009 (May 14) Glaucus atlanticus from Pacific coast of Panama. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/22416

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My Glaucus atlanticus Report

May 14, 2009
From: Kenneth Hattersley

Concerning message #22410:

Here is my school report on Glaucus.

 Glaucus atlanticus, a member of the phylum Mollusca, is a magnificent creature. Sometimes the G. atlanticus is referred to as the Blue Slug, Sea Lizard, and sometimes Sea Dragon. I will relinquish my vast knowledge and explain to you the mating habits, eating habits, ways of living, defensive measures, and other random facts based on this wonderful creature. Let's begin our journey through the anatomy and life of the Sea Lizard, starting with its unique food intake.

To start off, this slug is basically anywhere the Porpita porpita (Blue Button), Velella velella (simply known as velella or the By-the-Wind-Sailor), and Physalia physalis (Portuguese Man of War) are found. The reason behind this is that the slug feeds on these specific members of Hydrozoa, but more exclusively the Physalia. These blue slugs use something called rhinophores to seek out their prey. A rhinophore is essentially a sense of "smell." The word comes from two Greek words, Rhino meaning nose, and phore meaning carrier. People use their noses to pick up scent causing chemicals in the air with receptors that send messages to be deciphered by your brain. This is the same basic idea with rhinophores. The rhinophores pick up the chemicals in the water and sensory receptors, once again, send them to be deciphered by the slug's brain giving them an alert as to which way food is. They then attempt to propel themselves in that direction, this propulsion problem I will discuss later. Once the prey is found the daring slug will latch itself to the tentacles of the feared Portuguese Man of War and go to town. Interestingly enough the slug is immune to the powerful sting, and turns it around and uses it for its own benefit and protection, once again to be explained further on. The slugs not only eats these members of the Hydrozoan family, but will in a lot of cases as a result of limited food or close quarters, eat its own kind. In a lot of cases the Sea Dragon will come across one of its own and begin to eat it head first, slug cannibalism. This cannibalism was completely unheard of until somewhat recently. The Sea Lizards accomplish the task of eating the thick, chitinous outer layer of their prey velella and their own kind with the help of their own chitinous, razor like teeth that interlock like a zipper when the slug closes its mouth. There is a single long row of razor sharp, curved, pointed teeth all of which are serrulated like the leaves of a rose or the sharp side of a bread knife which are specialized for tearing through the hard, chitinous, outer rim, called the tentaculiform papillae, of their prey.

This slug also has another crazy feature... its unique defense mechanism. This slug eats the tentacles of poisonous, deadly hydrozoans and, while doing that sorts the nematocysts and picks out the most venomous of them and uses them for their own protection. The slug stores these stolen nematocysts in the cnidosacs in the ends of their cerata, or tentacle like structures at the end of the "arms," for future use. Due to this unique defense, G. atlanticus can deliver a much more deadly, painful sting than that of a Man of War. Australian kids have a game they play with the washed ashore bodies of the Man of Wars, or so called by them Blue Bottles, where they pick them up and throw them at each other. Sounds dangerous to me but people grow accustomed to a lot of things; anyway, as they play this game they sometimes accidentally stumble across a Glaucus, pick it up and hurl it at their buddy, delivering a much more painful sting. This is due to the way these creatures choose the nematocysts. It is said that the blue color is a "tell tale" sign of "Danger! Do not touch!" Therefore the G. atlanticus is very usually left alone. As you can see, accidents sometimes happen. In the water it is not known if the slugs mistake humans for food due to smell and migrate towards people (don't know why they would), but in any case that isn't a threat due to the method of movement.

The G. atlanticus has a very interesting, yet little known about mode of transportation. This slug has an air sac on what seems to be the dorsal side. However, although it looks as though the side of the Sea Lizard you can see in the photograph above is the dorsal side, it isn't. The G. atlanticus spends its life floating along the top of the water, dorsal side down and foot up, just cruising along in search of food putting its rhinophores to use. I'm not quite sure how the Sea Lizard gets to the food its rhinophores help locate. This is the only thing about this creature that somewhat baffles me. Movement is not actually controlled by the slug itself. Although it has been seen to try, the slug is not able to control its own movement. The slug can sometimes be seen attempting to wriggle its way across the sea along the top of the water, but self propulsion for this species of slug is a fail. The Sea Lizard relies on the wind and ocean currents but either way this is a pretty interesting, slow way of movement and altogether life. The Blue Slugs entire life after the larval stage is spent upside down floating on its back buoying itself with its air sac. An interesting touch to this slug's defense is its coloration.

The foot (which faces upwards) is colored a dark blue to grey to camouflage itself from predators that attack from above such as seagull or pelicans. Its underside (dorsal on this specific creature) is a light, silvery grey to keep safe from predators from below suck as sea turtles, that also eat Man of Wars thus, are immune to the slugs powerful sting.

These creatures mating habits are also very abnormal. The Blue Slug is what is called a hermaphrodite, meaning it is both sexes in one. It has a hole on the right side of its body (when looking for dorsal side) between the two larger ceratal clumps, holding both the male and female reproductive organs. It has been said that the creature cannot, or just does not fertilize itself. The slug has an immensely long penis, sometimes longer than its body. Reason for this abnormally larger reproductive organ is to have the ability to reach past the out hanging ceratal clumps of its potential partner. The only other animal that's penis size in relation to body size that can rival that of the Sea Dragon is that of the sessile creature the barnacle. Barnacles have the largest penis in relation to body size in the entire animal kingdom. Back on topic, the female organs produce egg strings that either spiral or string out of the hole that seems to be on the left if the slug is viewed overlooking the foot. Each egg string will hold 12-20 eggs in them. The eggs in this egg string will remain attached to each other until the larvae hatch and are on their way. A lot of times, in stress, the slug will Evert its penis for no apparent reason whatsoever. In one case, a man was watching the mating process and reported seeing a larger of two Glaucus attempting to eat the others penis before mating. Now, there have never been any other reports of before mating one eating the others reproductive organ but it is said that this could be possible due to the often cannibalistic ways of the Blue Lizard. Another question also arose during my reading...is there a preference of being either male or female during mating? The answer came up soon after, with a response that stated that during mating both slugs involved will be male and female releasing both sperm and eggs in one mating session. There is also another sea slug very closely related to the G. atlanticus.

This almost identical relative of the Glaucus is known as the Glaucilla marginata. These two slugs are almost exactly alike with few key differences. To start this section off we will begin with a common factor. These two slugs both have what is called bilateral symmetry, in other words if you were to cut them in half directly down the middle it would be exactly the same on both sides. Both sides have the same amounts of cerata that are all equal in length and width. I'm not certain whether the amount of nematocysts is the same on both sides but considering the bilateral symmetry, I'd imagine they would be. The colors and designs along the dorsal and foot are also equal on both sides of the slug. Both slugs have eyes that extend from their heads and can see in all directions. Now, one of these key differences that set these two similar slugs apart is size. The Glaucus is much larger in size ranging from about 2-3 mm as a juvenile to 20-30 mm or more as an adult (*note* these creatures are found mainly in Australia, thus, the metric system is used). The smaller Glaucilla gets only to about 5-10 mm as an adult. Both of these creatures feed on the same things and have the same method of movement, but I assure you size isn't the only difference. The cerata of the G. marginata, unlike those of the G. atlanticus, are multi layered, having several overlapping rows of cerata. The cerata of the G. atlanticus have only one row of longer cerata per "arm." The locality of these creatures varies widely.

Attempts to keep these creatures in captivity with one another has turned out to be an extreme fail, resulting in death of the majority of the captive slugs due to cannibalism and the eventual death of the remaining captives due to one thing or another. The idea behind such quick death in these captive specimens is thought to be because of the fact that the slugs in captivity were found on the beaches and had been there for periods of time, and had probably been roughed up quite a bit by the waves as they came in. No matter how long they last in captivity the will always be happier in the ocean where they belong.

The locality is definitely needed to go into with more detail. As I stated previously, the Sea Lizard basically follows around its food source, the Portuguese Man of War, to all stretches of the earth. In hearing that, you can now assume that the locality of these magnificent, complex creatures is not partial to one specific region. They call any warm, sub-tropic, salt based body of water home. From the waters of Africa and South Eastern Europe, to the coasts of Australia, and even in our own backyard, right here in the Gulf of Mexico. So when you're visiting the beach over summer and those strong winds are blowing in off the coast, they are bringing more than the easily visible Man of Wars. If you spot a Man of War, be wary and take extra caution as these little floating slugs are much harder to see than the hydrozoans, due to their miniscule size.

As you can see if have taken a liking to these beautiful, awesome, complex creatures the Glaucus atlanticus, and have learned basically all there is to know about the natural marvels...from their eating habits, to their form of motion, to the way they make babies. I now have passed this information on to you.

Kenneth Hattersley

little_kenny_h@yahoo.com

Hattersley, K.P., 2009 (May 14) My Glaucus atlanticus Report. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/22413

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Glaucus atlanticus in Gulf of Mexico?

April 7, 2009
From: Kenneth Hattersley

Concerning message #18991:

Bill,
I am somewhat concerned ... I tend to go to the beach quite frequently through the summer months. I live right off the Gulf of Mexico in Corpus Christi, Texas and visit the beach on a semi-daily basis. I see a lot of the hydrozoans referred to as the Portuguese man of war and am wondering does Glaucus atlanticus tends to show up in the Gulf of Mexico as well? As you probably know, I am wondering this out of concern for myself and little brothers and sisters as I am only 17. These little creatures though amazing as they are, are quite frightening considering their devastating sting.

Thanks,
Kenneth Hattersley
High School Student

little_kenny_h@yahoo.com

Hattersley, K.P., 2009 (Apr 7) Glaucus atlanticus in Gulf of Mexico?. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/22410

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Re: Tiny, elaborate creature at Stradbroke Island, Queensland

March 17, 2009
From: Paul Stewart

Concerning message #21205:

Hi Bill,

With reference to the email above I wonder if the animal is in fact Glaucilla marginata

In Glaucus the cerata are arranged in a single row in each arch while in Glaucilla there are multiple rows.

In the link below I have photographed both species for comparison.

http://www.flickr.com/photos/29056374@N04/3344062842/

Paul Stewart (flicker username paulhypnos)

hypnos1@live.com.au

Stewart, P. A., 2009 (Mar 17) Re: Tiny, elaborate creature at Stradbroke Island, Queensland. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/22333

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Glaucus atlanticus from Kenya

January 8, 2009
From: Debs North

Concerning message #11959:

I was so pleased to find this site today. When I was a very small child, living in Kenya, I found a large number of (what I now believe to be) Glaucus atlanticus washed up along the shore near Mombasa. For the last forty years I have remembered and marvelled over the sight, sometimes being told that I had imagined these wonderful little dragons. Today, I discovered, thanks to you, that it was real. Thank you so much!

Locality: Belkeith, near Mombasa, shoreline, Kenya, Indian Ocean, 1965ish, coral sand inside the reef. Length: 10 - 30 mm

Debs North

deborah.north@orange.fr

North, D.R., 2009 (Jan 8) Glaucus atlanticus from Kenya. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/22118

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Tiny, elaborate creature at Stradbroke Island, Queensland

December 3, 2007
From: Ken Thomas

Hello,
I'd be very grateful if anyone could identify this mysterious creature, seen at Stradbroke Island on 12 November.  These were scattereed along the waterline on the eastern, exposed beach which was quite rough at the time.
The photo is quite close-up, and the actual size of the animal is about 3-4 mm across.

Locality: North Stradbroke Island, --, Queenslandd, Australia, Pacific, 12 November 2007, at waterline on sand beach with strong surf. Length: 3.5 mm. Photographer: Sandi Somers.

Best regards,
Ken Thomas

ken@netgain.net.au

Thomas, K, 2007 (Dec 3) Tiny, elaborate creature at Stradbroke Island, Queensland. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/21205

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Glaucus atlanticus from Pacific coast of Mexico

March 7, 2007
From: Joe Weiss

I found several of these tiny animals on a Pacific beach about 40 km north of Ixtapa, Mexico on February 23rd. Some small blue jellies washed up at the same time. The animals were only 2-3 mm in length. Brilliantly dark-blue dorsal side with silver underneath. Are they developing juveniles?  I would appreciate any help in identifying them.

Locality: Troncones Beach, washed up on beach, Mexico, Pacific, 23 February, 2007, sandy beach. Length: 2-3 mm. Photographer: Angelina Gregorio.

Joe Weiss

weiss_joe@msn.com

Weiss, J.M., 2007 (Mar 7) Glaucus atlanticus from Pacific coast of Mexico. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/19551

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Sea Lizard [Glaucus atlanticus] from New South Wales

March 2, 2007
From: Lynne T.

Just like to say what a great forum!!
I have been fascinated with "the blue tide" animals for many years. I recently held a few Glaucus atlanticus to take some photos. Could you tell me what the circle opening is on their left hand side and what body part comes out and goes back in? I have included a photo and the Glaucus at the top has the protruding part????

Locality: Coalcliff Beach, shore, New South Wales, Australia, Pacific Ocean, 27 Feburary 2007, washed up. Length: 30 mm. Photographer: Lynne the lifeguard!.

Lynne

ctuck@netspace.net.au

Lynne T, 2007 (Mar 2) Sea Lizard [Glaucus atlanticus] from New South Wales. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/19561

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Glaucus atlanticus mating habits

January 29, 2007
From: Johanna Schwartz

Great site! Very informative.

I am currently doing some research for a documentary film and was wondering where I could find more information on the mating habits of these blue ocean slugs.

Am I right in thinking that even though they posses both male and female organs, they are unable to fertilise their own eggs? They have to mate with each other in order to reproduce, correct?

I have seen footage of two slugs balled up with their penis' out. The commentary talked about the slugs trying to bite each other's penis off. I haven't seen anything about this on your site though. I'd like to know more.

Which leads me to one further thought: do they prefer to do the fertilising rather than be fertilised, i.e. be male instead of female?

Many thanks!
Johanna Schwartz

johanna_schwartz@hotmail.com

Johanna Schwartz, 2007 (Jan 29) Glaucus atlanticus mating habits. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/19328

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Glaucus atlanticus in Hawaii

January 16, 2007
From: Nichol Miura

We didn't know what it was until we came home and did some research online. Unfortunately, we don't have a picture at this time. We also found a juvenile Portuguese Man-O-War [Physalia] and a Purple Bubble Raft Snail [Janthina ] (though we didn't know until we saw all of the other photos). Thanks for having such a wonderful site.
We had a question. We read that it "can severely sting humans", could you elaborate on that? Thanks again for all of the great information.

Locality: Oahu, near Mokoli'i Island (21* 30'43.00" N, 157* 50'09.00" W), floating with tide, Hawaii, USA, Pacific Ocean, 14 January 2007, Clear warm waters. Length: 1 inch by 1 inch

Nichol Miura

nmiura13@hotmail.com

Miura, N., 2007 (Jan 16) Glaucus atlanticus in Hawaii. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/19235

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What type of Nudibranch is this?

January 15, 2007
From: Adrian Giles

 

What type of nudibranch is this?
I have attached photos of some, what I believe to be nudibranchs, that washed up all along Seven Mile beach Lennox Head/Broken Head, Northern New South Wales

Locality: Seven Mile Beach,  NSW, Australia, 10 January 2007

Adrian Giles

adrian.giles@dimensiondata.com.au

Giles, A., 2007 (Jan 15) What type of Nudibranch is this? . [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/19205

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Re: Glaucus atlanticus on Gold Coast, Queensland

January 15, 2007
From: Rob Alesbury

Concerning message #18991:

I counted about 30 of these creatures washed up on a small area of beach at Byron Bay, NSW, Australia on 14 December 2006. I have been trying to identify him since I returned from holiday. Are they unusual in this area?

Locality: Byron Bay, NSW, Australia, Pacific, 14 December 2006, Sandy Ocean Beach. Length: 15mm. Photographer: Rob Alesbury.

Rob Alesbury

robbiealesbury@hotmail.com

Alesbury, R., 2007 (Jan 15) Re: Glaucus atlanticus on Gold Coast, Queensland. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/19223

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Glaucus atlanticus on Gold Coast, Queensland

December 14, 2006
From: John Campbell

Concerning message #16552:

On patrol with many long serving members and meeting older beach goers today no one had seen these little fellas [Glaucus atlanticus ] before. People were very curious and unsure of the stinging power of them as they carry that tell tale blue colour "dont touch". Are they here to stay? Or have they fallen off an Indonesian fishing boat? I read the notice of a Fraser Island sighting and am sure they are new to the region. They would be a much welcome relief from the blue bottles that arrive every summer with the northerly winds, but the number of them is a little disconcerting none the less.

Locality: North Burleigh Beach, Gold Coast, on Beach, sthn Queensland, Australia, Pacific Ocean, 10 December 2006, Sandy Ocean Beach . Length: 10 - 20 mm

John Campbell

j.campbell@burnsdesign.com.au

Campbell, J., 2006 (Dec 14) Glaucus atlanticus on Gold Coast, Queensland. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/18991

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Glaucus eating Porpita in Hawaii

August 17, 2006
From: Anna-Christina Amason

My mom and I found it (actually, it found us) in the waves at Hapuna beach (on the Kohala coast) last Wednesday, alive and well, and returned it as soon as we photographed it. It was the most amazing creature, very silver and blue. At first we thought it was someone's small plastic toy, but quickly realized it was a real creature. There were quite a few Porpita porpita, all different sizes, out that day and we also saw a tiny Man Of War float, nothing else was left.

Locality: Hapuna Beach, Hawaii, 1 meter, Hawaii, USA, Pacific, 8 August 2006, beautiful, clear water. Length: 1 cm. Photographer: Anna-Christina Amason .

I thought you might want to know, not many people have reported seeing them in the Hawaiian islands, especially Hawaii.

Anna-Christina Amason (11)

susan@tibcomm.com

Amason, A., 2006 (Aug 17) Glaucus eating Porpita in Hawaii . [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/17476

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Feeding and some trophic interactions of Glaucus atlanticus

August 2, 2006
From: Irina Roginskaya

Dear Bill,
I want to add to my previous messages (Roginskaya, 2006, 2006a) some more field observations of Dr.A.I.Savilov (1956,1971), concerning the feeding behaviour of Glaucus atlanticus. And to show two pictures from the set of my recent SEM photos of details of buccal apparatus of early juveniles of Glaucus from the material , collected by A.I. Savilov in 1961 in Tropical Western Pacific.
A.I. Savilov writes: " The hungry Glaucus, holding on to Velella by the ends of tentaculiform papillae, starts to tear off and engulf the rather big pieces of the floating disc of the siphonophore . Sometimes Glaucus, bending its body, captures the edge of the disc, gnawing a whole section of the colony of polyps". (see Upper right drawing: - Glaucus eating Velella - the original illustration of A.I.Savilov in Priroda ).

The buccal armature of Glaucus includes stout chitinous jaws with rather well developed long serrulated chitinous masticatory borders with a single row of multiple curved pointed denticles (fairly even in size) along the cutting edge.(I counted more than 45 denticles on the masticatory process of a juvenile Glaucus 1.5 mm long in spirit).[see Photo B: SEM photo , x600]. When the mouth of Glaucus is closed, and the odontophore is retracted, the matched rows of denticles along the cutting edge, create a strong construction, which reminds me of a real zip fastener [see Photo C: SEM photo of the part of  "zipper". x2000 of the juvenile Glaucus 1.2 mm long in spirit].

Locality: Open Ocean, surface of water, Tropical Western Pacific, 18 September 1961, pleuston. Length: 1.2 -1.5 mm. Photographer: Irina Roginskay, Viktor Karlov.

Both specimens are from the material of A.I.Savilov, collected during the cruise no.34 of R/V "Vityaz" in the Tropical Western Pacific; Sta.5086 (3 2'N, 140 8'W), 18.Sept.1961). May be these denticles help juvenile Glaucus to grasp portions of the prey and keep attached in mobile surroundings. The worn and even completely broken denticles I discovered on the masticatory borders of some minute juveniles of Glaucus, suggests that the process of feeding sometimes demands considerable efforts by juveniles and that the denticles on the cutting edge have an important role in the primary feeding.

There are very contradictory opinions by different authors concerning the predator prey interactions betweem Glaucus and Janthina. Perhaps the perfectly equipped buccal mechanism permits specimens of Glaucus from South Africa to attack and feed on the pelagic shelled gastropods Janthina.   Barnard (1927) indicates Janthina as the main food item of his specimens of Glaucus. Though this seems rather unusual and puzzling for a cnidarian-feeding nudibranchs.  A.I.Savilov (1971) stated on the contrary that Janthina janthina, collected during the cruise of R/V "Akademic Kurchatov" in the region of the Peru Current and kept in the aquarium with juvenile Glaucus from the same catch, successfully attacked them. Savilov even suggested that the almost complete absence in September 1968 of juveniles of Glaucus in the middle parts of Peru current, where the mass development of the population of J. janthina had been observed, could be linked not only with advancement along the Peru Current of different generations of Glaucus, but with the eating of juvenile Glaucus by Janthina.

In the observations by R. Bieri (1966) Janthina were absolutely indifferent to Glaucus: " Several times I placed active Glaucus close to Janthina prolongata, but they were never attacked and never elicited the feeding response in Janthina."

I came across another quite amazing statement of R. Buchsbaum and L.I. Milne (1962): "In warmer seas far from land the deep-violet blue nudibranch Glaucus eucharis creeps along on the underside of the surface film scavenging for minute plants and animals". Perhaps the authors mean that Glaucus eats the sutface-dwelling larval stages of Velella - Rataria?

• Barnard K.H. 1927. South African Nudibranch Mollusca with description of new species and a note on some specimens from Tristan d'Acunha. Annals of the South African Museum, vol.XXV, no.1, pp171-215, pls.19-20.
• Bieri R. 1966. Feeding preferences and rates of the snail Janthina prolongata, the barnacle Lepas anserifera, the nudibranch Glaucus atlanticus and Fiona pinnata and the food web in the marine pleiston. Publications Seto Marine Biological Laboratory, vol.XIV, no.2,pp.161-170, Plates III-IV.
• Buchsbaum R. and L.J. Milne.1962. The Lower Animals.Living Invertebrates of the World. 303 pp. Published by Doubleday and Co.,Inc. Gordon City, New York.Third printing.
• Roginskaya I.S. 2006.(May 9). Some notes about Glaucus atlanticus.[Message in] Sea Slug Forum.Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/16534
• Roginskaya I.S. 2006a. (May 25). About egg masses of Glaucus atlanticus. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/ 16663.
• Savilov A.I. 1956. Floating biocoenosis in the Pacific Ocean based on the material of the Expeditions of the Institute of Oceanology, Academy of Sciences USSR. Priroda, vol.45, no.3, pp.62-68.
• Savilov A.I. 1971. Pattern of Pleuuston Distribution in the Region of the Peru Current. The Academy of Sciences of the USSR. Transaction of the P.P.Shirshov Institute of Oceanology. vol.89. Oceanologic Investigation in the Peru Current Area, pp.60-76.

irina7@hotmail.com

Roginskaya I.S/, 2006 (Aug 2) Feeding and some trophic interactions of Glaucus atlanticus. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/17264

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About egg masses of Glaucus atlanticus

May 25, 2006
From: Irina Roginskaya

Concerning message #16534:

Dear Bill,
I couldn't find information from reliable sources about the coiled form of the egg masses of Glaucus atlanticus - except this one. The only mention about spiral spawns deposited by Glaucus I found in the Russian Monograph  Life of Animals,1968 (in Russian). The authors of the Part "Mollusca" in this book - two well known Russian malacologists (not "branchers") B.V. Vlastov and P.V.Matyokin, on pp.65-66, discussing the morphological differences enabling Glaucus to live at the surface layers of the sea, also touch upon the egg-laying of this slug.
" This slug deposits eggs in the form of spiral ribbon, sticking it to the bell of Velella, after eating the polyps of the Velella ". [my translation].

Most authors are of opinion that the eggs of Glaucus are deposited as short, straght lines. W. Macnae (1954, p.48} even emphasizes the fact that the egg masses are not coiled.
" From the lumen of the oviduct in the region of the albumen gland several short strings of eggs were removed. Similar short, uncoiled strings about 2cm long were laid by specimens kept under observation in finger-bowls. This method of egg-laying , which is so different from other Eolids, may account for the fact that the albumen gland is neither so voluminous, nor so thick walled as in other members of the order. Each of the strings contains about 12 to 20 eggs in a single series"

The egg-strings protruded from the oviduct of one specimen of Glaucus atlanticus from the Pacific Ocean in my catch (Roginskaya, 2006) were also in the form of short straight lines. The pictures of straight short egg-strings or its fragments were displayed in many publications (e.g. R. Bergh, 1864; A. Bebbington,1986; W.B.Rudman,1999; etc.). Maybe the unusual method of depositing eggs was evolved by Glaucus because of the difficulty of building regular spirals in mobile surroundings - the oceanic surface layers, subjected to the influence of winds and currents, where the main problem is the difficulty of keeping close to Chondrophora and quickly attaching eggs to the floating object.

• Bebbington, A. 1986. Observations on a collection of Glaucus atlanticus Gastropoda, Opisthobranchia). Haliotis, vol.15, pp.73-81.
• Bergh,Rud. 1864. Anatomiske Bidrag til Kundscab om Aeolidierne. Kongelige Danske Videnskabernes Selskabs Skrifter, 5te Raekke, 7 te Band. 175 pp.
•  Macnae, W. 1954. On some Eolidacean Nudibranchiate Molluscs from Southern Africa. Annals Natal Museum, vol.13, part.1,pp.1-50.
• Roginskaya, I.S. 2006.(May, 9) Some notes about Glaucus atlanticus. [Message in] Sea Slug Forum.Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/16534
• Rudman,W.B.1999 (May 16) Comment on eggs of Glaucus and Glaucilla by Bill Rudman. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum,net/find/867
• Vlastov B.V. and Matyokin ,P.V. 1968. Order Acoela pp 62-67. In ; Life of Animals, vol.2. Invertebrates [Ed. L.A.Zenkevich.] Publishing House "Prosveschhenie".Moscow.

Irina Roginskaya

irina7@hotmail.com

Roginskaya I.S., 2006 (May 25) About egg masses of Glaucus atlanticus. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/16663

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Unknown creature from Fraser Island, Queensland

May 9, 2006
From: Richard Wilsher

I would be grateful for any identification of the attached creature. I am a lay-person in this field but my lay-interest suggests this may be a free-swimming sea slug. An expert opinion would be much appreciated.

Locality: Fraser Island, eastern (ocean) shore, beach, QLD, AU, Pacific, 25 April 2006, washed ashore, numerous (one approx every 5 m). Length: 20 - 30 mm (specimens varied). Photographer: Richard Wilsher

Note - since your site is presumably of international significance I recommend use of the international date format as defined in ISO 8601, ccyy-mm-dd. This is used significantly and increasingly within scientific and industrial sectors

Many thanks,
RGW.

RichardG@Wilsher.net

Wilsher, R. G., 2006 (May 9) Unknown creature from Fraser Island, Queensland. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/16552

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Some notes about Glaucus atlanticus

May 9, 2006
From: Irina Roginskaya

Dear Bill,
I am so glad the Forum is back! We really felt orphaned without daily opisthobranch news from all the world!

I am sending you two photographs of Glaucus atlanticus I took (as you can see from their quality) in predigital epoch) (Zenith-E camera). Three specimens of G. atlanticus were collected by pleuston net during the cruise no.59 of R/V "Vytiaz" in the Pacific Ocean.(Sta.7505, 34 17'9 N, 143 52'0 E, June 25 1976) together with their food objects hydrozoan cnidarians, the Chondrophorina: Velella with a keel-like "sail" elevated above the surface of water and disk-shaped Porpita ( the latter on photo 1) . The body length of the Glaucus in spirit 12.0 mm, 13.5 mm (dissected) and 16.5 mm. Diameter in spirit ot the disk of Porpita = 10 mm. The radula of dissected specimen contained 14 rows of teeth. This specimen was in the process of egg-laying , as the bead -like egg-strings were appearing from the oviduct. It seems to me that there were no photos in the Forum of G. atlanticus from this area.

Locality: 34 17' 9 N, 143 52' 0 E, surface of water, Open Ocean, Pacific Ocean, 25 June 1976, collected by pleuston net. Length: 12.0 mm, 13.5 mm, 16.5 mm in spirit. Photographer: IrinaS.Roginskaya

As recently a lot of messages, touching upon the feeding, egg-laying, cannibalistic habits etc. of  Glaucus appeared in the Forum I couldn't resist the temptation to add some information concerning Glaucus, mainly from the observations of the late Dr. A.I.Savilov from the P.P.Shirshov Institute of Oceanology , Moscow,  Russia (Savilov, 1956,1968). Perhaps these works are unknown to you and colleagues as being published in Russian only.

Dr.A.I. Savilov (1913-1969) - marine biologist, the well known specialist of the surface fauna of the ocean, keen observer, amateur graphic artist, participant of many scientific ocean cruises. You can find in his papers a lot of life history characteristics of bouyant organisms: Glaucus, Glaucilla, Fiona, Janthina, Physalia, Velella, Porpita, Actiniaria etc. The fragments of  text I cite here are from two papers of A.I. Savilov [my translation - so please be understanding] .

From Savilov,1956, page 65:
"Glaucus is a carnivore, feeding on Velella. It prefers to keep freely on the surface of water and approaches the prey only being hungry. For long hours during the drift of "Vytiaz' we looked closely from the board at the surface of the ocean in hope to reveal Glaucus in the middle of floating past Velellas. At last we were lucky to discover it. In the slightly splashing water we noticed an exemplar of swimming Velella and behind it broadly spreading their papillae the pair of Glaucus keeping on the surface. The velvety-blue coloured molluscs were nearly invisible on the background of the blue-green ocean depth. Sometimes when the Glaucus were thrown away by wave or a splash of water, they rather quickly, paddling with the bundles of papillae as with oars, rowed back to Velella."

This contrary to the opinion of T.E.Thompson and I.D.MacFarlane (1967) that "small contractions and movements of the cerata and metapodium are not directional in function. Glaucus is thus planktonic rather than pelagic" and later of T.E.Thompson (1976), considering glaucid nudibranchs to be passively planktonic as the movements of their cerata "do not appear to result in translocation". P. Bieri was aware of these field observations of Savilov (1956), concerning the intentional swimming of free-living Glaucus atlanticus to its prey. (Mr. Saburo Nishimura kindly lent him his translation of Savilov's report). But R. Bieri stated that the specimens of Glaucus in his experiments - maintained in jars with running water - could not swim. I think that as these laboratory observations may not reflect the conditions in the open sea, the behaviour of his Glaucus could be greatly affected by maintenance in captivity. By the way, A. Fredol characterizing Glaucus wrote: "Quoique paresseux, il nage avec vitesse". If the observations of Savilov (1956) are not accidental we can consider Glaucus to be a pelagic organism rather than a planktonic one.

P. Bieri (1966) already described the cannibalistic habits of his specimens of Glaucus:
" Glaucus frequently attacked one another and bit off pieces of tail and 'arms". One 20 mm long individual ate all but the head and trunk of a 15 mm long individual in 30 minutes." And further in the Discussion: "Glaucus prefers Physalia. On the other hand, when food is in short supply or after periods of prolonged starvation, the niche differentiation probably breaks down and then even cannibalism is practiced by Janthina and Glaucus. (The same situation as described by Peter Whiter (Whiter, P. 2006 .March 28) and earlier by R. Armstrong (Armstrong, R.1999. Feb.26).

A.I. Savilov (1968) describes the egg-laying of Glaucus.:
" For egg-laying, Glaucus needs floating objects. They attach their egg-masses to the skeleton plates of dead Chondrophora and small driftwood". He also emphasizes the importance of Chondrophora as distributional and topical factor (page 292). " The skeletal plates of Chondrophora after being picked clean by predators, retain their bouyancy for a long time and are frequently used for attachment of egg masses. Some species (Glaucus, Halobates) utilize these plates for laying their cocoons and eggs, the others - for attachment of their juveniles during the first days of their life (Lepas ), until their own floats are produced; some species inhabit skeleton plates either permanently (Fiona, Turbellaria) or temporary (Planes, Isothea, Metapennaeus)".

There is similar data about the egg-laying of Glaucus  in the monograph of W.J. Dakin (1953). He indicated (pages 270-271) that " Requiring something a little more substantial than water on which to deposit its egg masses , Glaucus feeds on Velella, lays its eggs on the skeleton framework of the creature it has been eating".  Maybe only in the absence of suitable substrata are specimens of Glaucus  forced to deposit their egg-strings directly on the surface where they float. (Rudman,1999. Feb 25). Thompson and MacFarlane (1967) admit both modes of egg-laying: " Strings of eggs each consisting of 12 to 15 eggs are shed into the sea, or attached to the prey".

• Armstrong, R.1999 (Feb.26) Re: Glaucus in New Zealand. Message in Sea Slug Forum. Australian Museum,Sydney. Available from http://www.seaslugforum.net/find/616
• Bieri R. 1966. Feeding preferences and rates of the snail, Janthina prolongata, the barnacle Lepas anserifera, the nudibranchs Glaucus atlanticus and Fiona pinnata and the food web in the marine pleiston. Publications Seto Marine Biological Laboratory, vol.XIV, no.2, pp.161-170, PlatesIII-IV.
• Dakin, W. J. 1953. Australian Seashores. Angus andRobertson.
• Fredol, A. 1866. Le Monde de la Mer. Deuxieme edition. vii+693 pp. Paris. Librairie de L.Hachette etC.
• Rudman , W.B. 1999. (Feb 25). Comment on Glaucus in New Zealand. Message in Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/616
• Savilov, A.I. 1956. Floating biocoenosis in the Pacific Ocean based on the material of the Expeditions of the Institute of Oceanology, Academy of Sciences USSR. Priroda, Vol.45, no.3,pp.62-68.
• Savilov A.I. 1968. Pleuston of the Pacific Ocean.Pages 264-353 in the Monography "Pacific Ocean. Biology of Pacific Ocean ". Part 2. Moscow. Academy of Sciences of the USSR. Institute of Oceanology."Nauka".
• Thompson T.E. !976. Biology of Opisthobranch Molluscs.Vol.1, 207 pp, London The Ray Society. No151.
• Thompson T.E. and Mac Farlane I.D. 1967  Observations on a collection of Glaucus from the Gulf of Aden with a critical review of published records of Glaucidae (Gastropoda, Opisthobranchia). Proceedings Linnean Society London. Vol. 178, no.2 pp 107-123.
• Whiter, P.A 2006 (Mar 28). Cannibalism in Glaucus? Message in Sea Slug Forum. Australian Museum, Sydney Available from http://www.seaslugforum.net/find/16189

Irina Roginskaya

irina7@hotmail.com

Roginskaya I.S., 2006 (May 9) Some notes about Glaucus atlanticus. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/16534

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Not sure if this IS a sea slug?

April 26, 2006
From: Mary Patterson

Hello,
I'm sending an image with this letter, hoping you can identify this interesting organism that I saw on a recent trip to Australia.

It was found along Alexandria Beach at Noosa National Park, in Eastern Australia. The size is about 5 cm diameter. A marine biologist in the states suggested a shell-less mollusk, but we were uncertain. As I've only ever seen one nudibranch in real life, I'm quite unclear as to which one of these is might be (or if it's even something else!).

Locality: Alexandria Beach, Noosa, on wet sandy beach, Queensland, Australia, Pacific Ocean, 23 March 2006, intertidal, clean sand. Length: 5 mm. Photographer: Mary Patterson.

This is a wonderful website; quite a resource! Thanks for any help you can give identifying this mystery (to me) organism!

Sincerely,
Mary Patterson

maryjpatterson@yahoo.com

Patterson, M., 2006 (Apr 26) Not sure if this IS a sea slug?. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/16367

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Glaucus at Anna Bay, New South Wales

March 31, 2006
From: Jim Doyle

Washed up on the northern end of Stockton Beach, Birubi Point, were a number of Glaucus along with blue bottles and other blue creatures. They differed from the photographs that I have seen in that they were extremely "fat". So much so that their bodies were larger than their appendages.
This was before they "blew" themselves up.

A couple of people reported being stung by them.

Locality: Anna Bay , Beach, N.S.W, Australia, Pacific Ocean, 26 March 2006, Surf line (tide line). Length: 1 - 3 cm

Jim Doyle

doylejim@bmr.net.au

Doyle, J., 2006 (Mar 31) Glaucus at Anna Bay, New South Wales. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/16206

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Re: Cannibalism in Glaucus?

March 30, 2006
From: Peter Whiter

Concerning message #16189:

As it gets close to 48hrs, I feel the need to give an update on the Glaucus atlanticus in captivity at Eden.

Firstly - interesting news, Since looking further into the Forum Anna is now sure that the first little one was infact a Glaucilla marginata (sorry for the mislead, and yes Bill if you so desire, fix my first post).

As noted before the largest one ate the smallest one, leaving 3, the next smallest (22 mm) eventually died, I would say as Bill noted due to the Surf prior to standing and being stranded for who knows how long. Yesterday a trip to the beach got a few Physalia and the remaining two have been tucking into one (each) of these this morning. Anna is looking after them and I'm trying not to interfere. We both thing maybe a water change (30 - 50 %) today or tomorrow.

Locality: Pambula Beach FSC, NSW, Australia, 27 March 2006, stranded on beach not quite storm seas .....but close. Length: 15, 22, 29, 35 mm. Photographer: Peter Whiter

But at this stage they look fine (well as fine as we think they are fine, movement and they are SURE attached to the Physalia )

We were a little concerned about the Physalia being dead in the tank so after they left them alone and not being able to see just how much they have eaten of the Physalia we removed 2 of the 4 Physalia out of the tank. later the Glaucus were found attached mouth-to-mouth with both Penis out, who knows about damage but were sort of easy to seperate (tho it was IMPOSSIBLE to separate the large one from the Glaucilla). Some hours later Anna being worried about how much they had (not) eaten and the fact that they could eat each other, decided to give them a piece of her Goldfish food (yes I freaked at this news too). One of the Glaucus was very receptive caught the food in its parapodia and worked its self to get the food to its mouth (yay) in a rather aggresive manner. The other not so aggresive in its manouvers and when it got the food to its mouth it didn't seem to eat it (guess we need to try a dif  brand) and went back to standard "glaucuring".

Time will tell
Pete

peter.whiter@gmail.com

Whiter P.A., 2006 (Mar 30) Re: Cannibalism in Glaucus?. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/16195

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Cannibalism in Glaucus?

March 28, 2006
From: Peter Whiter

Hi Bill,
I've been at your site for a few years its great. The main reason for visiting your site tonight was to research the Glaucus, my now Girlfriend (an Artist) has seen them before on the beach and has tried to keep one in captivity (tank, maybe bucket) without much success (it lived only a day or so). today we have the left over of recent Cyclone Waves arrive here (Eden far south coast of NSW) and she found 4 on her walk ... one small about 15 mm in length one about 22 mm (very damaged), then one at about 29 mm, one at 35. After getting them home and into a tank with aeration which seemed to perk them up a bit, a strange thing happened - the largest one attacked and killed the smallest one. The next smallest one (22 mm) may now be dead as he was not doing so well this afternoon.
I guess we have a couple of questions.

1. Do they keep in captvity and how do we prolong this if it is at all possible?
2. have you ever heard of cannibalism in them?

Hope these are a fair questions to ask.

Regards
Pete

peter.whiter@gmail.com

Whiter, P., 2006 (Mar 28) Cannibalism in Glaucus?. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/16189

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What the ?

March 23, 2006
From: Eve Whicker

Hi -
I am very curious about Blue Sea Slug [Glaucus atlanticus] behaviour - - - last weekend we had a huge wash up of Blue Bottle and Slugs on my home beach at New Brighton, just north of Byron Bay. We brought several specimens home to take some photos. Over the course of the afternoon I put them in a container together to get some pix of them en masse and the two largest joined up, rolled over, stayed that way for about 5 minutes then separated with a thingy (?) coming out of their sides. One turned over immediately, the other took a minute or two. I can't imagine that they have a need for male combat but then again who knows ? does any one have a clue ?

Locality: New Brighton Beach, nthn New South Wales, Australia, 18 March 2006. Length: largest 4 cm. Photographer: Eve Whicker.

Eve Whicker

eveii@bigpond.com

Whicker, E., 2006 (Mar 23) What the ? . [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/16154

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What is Filurus dubius?

February 24, 2006
From: Gary Rosenberg

Dear Bill,
I recently came across the name Filurus dubius De Kay, 1843 and am trying to figure out how to list it in Malacolog. Filurus is treated as a synonym of Glaucus at http://www.seaslug.com/systemat.html  and in  American Seashells (Abbott 1974) it is treated as a possible synonym of Melibe (Chioraera).  The original description (DeKay, 1843 -Zoology of New York, 5: 11) says the following:

Genus Filurus.
Tentacula two. Gills in two series along the back. Vent terminal. Caudal appendage long and filiform.

Filurus dubius.
Description. Body cylindrical, enveloped in a loose transparent membrane through which the intestinal tube is apparent. Along the back are two rows of branchial? processes, six in number on each side; at their tips, furnished with five or six spiculae: these are only seen when the animal is in motion. Mouth terminal, composed of a loose festooned membrane, alternately dilating and contracting when the animal is in motion; when dilated, two small transparent tentacula are protruded. The abdomen, or upper surface, appears to be composed of numerous rings. The caudal portion becomes abruptly smaller than the body, is long, cylindrical, and tapering to a point.

Color. Abdomen silvery white; dorsal region and sides light brown; tail light greenish. The color of the body, however, appears to depend on the contained viscera.

Length of body, 0.5; of tail, 0.7 [inches].

This curious animal was taken while swimming in salt water with its body reversed. Its motion was vermicular, and it appeared to be very tenacious of life, as it lived several days in a vessel containing salt water which had not been renewed.

De Kay did not provide an illustration or state where the specimen was collected, but presumably it is from Long Island Sound, New York.

I'd appreciate any thoughts on this creatures identity.

Best wishes,
Gary Rosenberg
Department of Malacology
Academy of Natural Sciences, Philadelphia, USA

rosenberg@acnatsci.org

Rosenberg, G., 2006 (Feb 24) What is Filurus dubius?. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/15932

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Glaucus atlanticus - habitat

February 21, 2006
From: Brandon Pinkney

I have been googling the Glaucus atlanticus for some time now but haven't been able to find its habitat It would be uber helpful if you know where it lives pleeeeeaaaaaassssse heeeeelllllllp!?!?!?!?!?!?!?!
Brandon Pinkney

blackessque_13_boi@yahoo.com

Pinkney B.J, 2006 (Feb 21) Glaucus atlanticus - habitat. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/15892

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Is this a sea slug ??

February 14, 2006
From: Karen Beal

My daughter took this photo of what we may think is a sea slug - but we are not quite sure really what it is. I wonder if you might be able to identify what it is as we are intrigued. It has such beautiful colours & markings.

She found it just a few feet from the sea & there seems to be a baby one just next to it (that has maybe just been born)?..... She said it was about the size of an english penny.

Locality: Byron Bay, nthn New South Wales, Australia. March 2005, a foot away from the waters edge. Photographer: Angela Beal.

Hoping that you can help.
Karen

kybkaren@aol.com

Beal, K., 2006 (Feb 14) Is this a sea slug ??. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/15798

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Blue Sea slug

February 2, 2006
From: Liliana Alaniz

I am currently going to middle school and am doing a project on molluska i picked Glaucus atlanticus for an example and need more info. hope you can help.

Sincerely,
Liliana

Lilichis93sd@aol.com

Alaniz, L., 2006 (Feb 2) Blue Sea slug. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/15734

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Glaucus atlanticus from the Canary Islands

May 23, 2005
From: Kim Boettcher

These washed up on Playa Las Vistas beach in Los Christianos, Tenerife, Canary Islands. On the shore they looked like shiny blue "blobs". My son put them in water and they opened up. Any help identifying them would be greatly appreciated.

Locality: Playa Las Vistas, Los Christianos, Tenerife, Canary Islands, Atlantic. washed up on shore. Length: 2 cms.19 May 2005. Photo: Kim Boettcher

Regards,
Kim Boettcher

canadakim@t-online.de

Boettcher, K, 2005 (May 23) Glaucus atlanticus from the Canary Islands. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/13848

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Information on Glaucus atlanticus

April 22, 2005
From: Kealy Baker-Clark

My name is Kealy and I am 9 years old. I am doing an assignment on the glaucus.I can't find information on whether this species is dangerous and why it is considered dangerous or if it is plentiful,rare or endangered. If you could help me with this information that would be good.

P.S. I am looking forward to getting an "A" for my work

Thank you,
Kealy Baker-Clark

dcla6425@bigpond.net.au

Baker-Clark, K., 2005 (Apr 22) Information on Glaucus atlanticus. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/13591

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Blue, lizard-like feather-finned tiny animal

April 14, 2005
From: Paiton Meurer

On the beach today in Highland Beach, Florida, we found on the shore a bright blue and silvery-white lizard-like animal. It was breathing and moving so we picked it up. We put it in some sea water, and it "opened up" and had fin-like-wings that were feathery and finger-like. It has a tail and a nose and mouth, inch long, some are very small, others are more healthy. They float on the top of the water and swim near eachother. Sometimes they roll up in little balls and flip around. It looked like it was eating parts of seaweed seeds.

Locality: Highland Beach, Florida, USA, Atlantic Ocean. Depth: Shoreline. Length: about 1 inch. 24 March 2005. By seaweed and shells on shoreline washed up.

Please tell me what this species is
Thanks.
Paiton Meurer

cthue22@aol.com

Meurer, P., 2005 (Apr 14) Blue, lizard-like feather-finned tiny animal. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/13425

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Glaucus atlanticus from Reunion Island

February 19, 2005
From: Philibert Bidgrain

Dear Bill,
Reunion Island sea slugs.

We have only one record of Glaucus atlanticus from Reunion Island.It was observed by Maurice Jay, floating on the surface of the ocean. A few years ago... Photo: Maurice Jay

Best Regards
Philibert Bidgrain
http://vieoceane.free.fr/runseaslug/indexslug.htm

pbidgrain@yahoo.fr

Bidgrain, P., 2005 (Feb 19) Glaucus atlanticus from Reunion Island. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/13096

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Found some interesting sea slugs in Florida

January 31, 2005
From: Sarah McDowell

Hi, this pat weekend, my roommate and I were in Pompano Beach, Florida, and she collected these sea slugs off the beach. Apparently the tide had washed them up, and she thought they would die there on the sand. Can anyone tell me what species these little guys are? They're really interesting looking, and I've never seen anything like them on the beach before. Thanks!

Locality: Pompano Beach, Florida, USA.
Length: >1 inch. 29 January 2005. Sand
Photographer: Sarah McDowell

Sarah McDowell

smcdowell5@bellsouth.net

McDowell, S., 2005 (Jan 31) Found some interesting sea slugs in Florida. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/13068

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Neon Blue sea slug from Fraser Island?

January 1, 2005
From: Neil Rhodes

This was found washed up on the beach on Fraser Island and photographed on the spot, it was not touched as the person taking the photo was unsure what it was. Described as being the size of a UK 50 pence coin.

Locality: Beach, washed up on sandy beach, Fraser Island, Queensland, Australia, Length: 12 mm. 12 November 2004. Photographer: Ginny Marsh

Vivid neon blue in colour with black tips to its feather appearance. Please help if you can, it may not even be a sea slug but heaving trawled through this forum it seemed to me that if anyone can identify this mystery its you guys.

Please help.
Many thanks and in anticipation

Neil

neil@digital-cameras.com

Rhodes, N, 2005 (Jan 1) Neon Blue sea slug from Fraser Island?. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/12868

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Is this a nudibranch?

January 21, 2004
From: Scott Godwin

My girlfriend and I found a small animal washed up on a beach about 40 km north of Port Macquarie, New South Wales [Australia]. It was about 4 - 5 cm in length, with a soft, muscular body like that of a gastropod but without the characteristic foot.

It had four 'arms' extending from its sides. The two anterior arms were longer than the posterior ones, and all four ended in a number of feathery appendages that looked to me like gills. There were more of these appendages extending posteriorly from the tail. The animal had two clearly visible eyes. It was a pale creamy white on the ventral surface and had very dark bluish black stripes running along the length of its dorsal surface and extending out along the 'arms'. I have included a sketch of the animal viewed from the dorsal side.
Scott Godwin

sgodwin@metz.une.edu.au

Godwin, S., 2004 (Jan 21) Is this a nudibranch?. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/11949

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Glaucus atlanticus from Sth Africa

January 21, 2004
From: Juleen du Toit

In January of 1998, my son and I found some little white blobs on the Muizenberg beach on the False Bay coastline of South Africa after a gale force southeasterly wind for about 2 days on the fringe of the waterline amongst loads of blue bottles.

Curious as to what it is, we inspected some by submerging them in sea water and discovered the most beautiful royal blue 'things' which was identified by the Two Oceans Aquarium on the Victoria and Albert Waterfront in Cape Town, South Africa as the nudibranch Glaucus atlanticus. It was quite a surprise to see on this site how far these delicate creatures are spread over the world! (Maybe one can't call them 'delicate' since they EAT blue bottles?? They sure like their food 'hot'!)

Since finding it the first time, I have found it during the summer months (now that you ID them as 'tropical' that makes sense) but unfortunately by the time it is washed out on the beach, it is dead. The Indian Ocean is the warmer side of the ocean surrounding the Cape Peninsula. The pictures are stunning and I am totally fascinated by these colourful beings. Thank you for such a load of information. My attempts at pictures feel rather feeble looking at these beauties.
Juleen du Toit

juleen@ananzi.co.za

du Toit, J., 2004 (Jan 21) Glaucus atlanticus from Sth Africa. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/11959

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Glaucus atlanticus from Queensland

December 3, 2003
From: Nick Falconer

Dear Bill,
Fantastic site and it just about answered nearly all the q's my kids had for me about the creature in the attached pics. There were probably about 10 - 20 of them varying in size on the high tide mark at Alexandra Headland [Sunshine Coast, Queensland, Australia] on Saturday. From your site info I gather they feed on the tentacles? of blue bottles but there were not a large number of bluebottles on the beach that day but they preceded a large blue bottle and big saturation of our beaches on Sunday of the (not sure of the scientific term) tri(something) weed. I'm sure you know the name. Where the beaches on the Coast becomes saturated in what looks like a polluted water/brown mass which is just the weed that comes off the reefs and settles on the beach.

Not sure if that has any relevance on my sighting of the nudibranch. It is however the first time in 25 years of living surfing/observing our beaches that I have seen them. One question I have is about the mushroom type brown attachment on its left side in my photo ..... is that a sexual organ / an effluent outlet? Sorry for all the questions but my kids are interested and want to present it at school and I am a photographer/journalist and wish to write a short article for our newspaper here.

Thanks in anticipation of your help.. fascinating creatures .. I released the little guy after photographing him at home.

Regards,
Nick Falconer

nfalconer@powerup.com.au

Falconer , N., 2003 (Dec 3) Glaucus atlanticus from Queensland. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/11581

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Glaucus from Wellington Pt, Brisbane

November 17, 2003
From: Mimi & Phong

Hello,
We came across this during a walk around Wellington Point, Brisbane [Queensland, Australia] and it looks rather cool, however we have no idea what it is, perhaps you could help?
Mimi & Phong

mythuynguyenle@hotmail.com

Mimi & Phong, 2003 (Nov 17) Glaucus from Wellington Pt, Brisbane. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/11427

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Glaucus in Hawaii

May 27, 2003
From: Chaunte Ling

Hi,
My brother found a sea slug at one of the beaches by my house. We live in Honolulu, Hawaii and this was the first time we saw something like it. I came home from boston and my brother and my dad had this weird looking thing in my fish tank. None of us knew what this little thing was. I stayed up late last night looking on the internet to figure what this thing was. At first I looked up jellyfishes, because when I was watching it is was kind of moving it's tenticles like a jellyfish. After awhile a blue sea slug website came up. This creature is very interesting and I was wondering if this sea slug is rare in Hawaii. I got to catch some man-of-wars to feed it and it was cool to watch it eat. If I were to catch some man-of-wars and put it in a jar would they be able to last or how long would they last? How do you tell if a sea slug is male or female? and How do you know if it is pregnant?
Thank you very much.
Chaunte

tay999@hotmail.com

Ling, C., 2003 (May 27) Glaucus in Hawaii. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/10028

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Mysterious blue and white swirley things

April 25, 2003
From: Sally

Hi kind sea slug experts
Today at Patchs Beach just south of Ballina [northern New South Wales, Australia] we discovered some creatures that sadly we did not photograph but to make life difficult for you we would love some information about them just based on our word of mouth. (trust us). These stunning creatures were approximately the size of a 20 cent piece, white and blue swirls with a head that resembled a seal and 4 webbed legs. Although we have visited many Sydney beaches quite frequently we have never met such interesting gorgeous creatures before and would love to know what they were so we could research them more fully
In true appreciation
Sally and Al.

ssally6@yahoo.com.au

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Re: Glaucus in Sydney

March 19, 2003
From: Alex & Marcus Dawes

Dear Bill,
Thanks so much for for your reply
- The website is awesome and full of useful and fascinating information. We are hooked!!

Alex (10) and Marcus (8)

dawes26@tpg.com.au

Dawes, A. & M., 2003 (Mar 19) Re: Glaucus in Sydney. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/9439

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Glaucus in Sydney

March 12, 2003
From: Alex and Marcus Dawes

Dear Bill,
We found this 'floating' in shallow water at Clovelly [Sydney, NSW, Australia] beach today .... We think it is a nudibranch of some kind but would be grateful if you can identify it from this (awful) photograph,,,

...It is 3 cm long and has silver and dark blue stripes (white underneath) ... Has 6 feathery limbs ... small head with horns or
antennae .... Looks poisonous!!

Our aunt saw something very similar at Pearl Beach on the Central Coast today .... Maybe it's an invasion?!
Thanks and Regards
Alex (10) & Marcus (8) Dawes

dawes26@tpg.com.au

Dawes, A. & M., 2003 (Mar 12) Glaucus in Sydney. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/9389

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Glaucus atlanticus from Lord Howe Island

January 24, 2003
From: W.B. Rudman

Here is a photo record from Ian Hutton of Glaucus atlanticus from Lord Howe Island.

Location: Lagoon Beach.

Bill Rudman

Rudman, W.B., 2003 (Jan 24) Glaucus atlanticus from Lord Howe Island. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/8963

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Glaucus atlanticus reference

November 14, 2002
From: Michael Schroedl

Dear Bill,
Could you help me with the full citation of Forster 1777, for Glaucus atlanticus please? I couldn't find that anywhere...
Thank you very much and all the best, Michael

schroedl@zi.biologie.uni-muenchen.de

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Glaucus atlanticus - observations

October 21, 2002
From: A. Lovatt.

Dear Dr Bill Rudman,
I saw a number of Glaucus atlanticus, and noticed that after some time, an object protruded from their left side just behind the first pair of "limbs". It had a sharp tip. The longest object I saw while watching, was about 10mm long. Some of the Glaucus atlanticus were as large as 60mm. I also observed that they attempted to propel themselves with some effect. The information that I have seen says (in some cases), that these animals are almost incapable of self propulsion.

Do you know what this object could be? Has there been any studies of how these creatures move?

Thank you
A. Lovatt.
New Zealand

Lovatt, A., 2002 (Oct 21) Glaucus atlanticus - observations. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/8233

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Thanks

June 15, 2002
From: Amanda Johnson

Thankyou very much for your help. I got an A on my assignment!
Thanks again.
Manda.

003421@bribislashs.qld.edu.au

Johnson, A., 2002 (Jun 15) Thanks. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/7261

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Glaucus atlanticus information

June 6, 2002
From: Manda

Hey
I'm doing a school project on Glaucus, I was wondering if you could tell me some things. I need to know about First Aid if you come into contact with one of these amazing little creatures as I can't seem to find anything anywhere else.

I also need a better idea of where they can be found around Australia.

Thanks heaps for your help
Manda

003421@bribislashs.qld.edu.au

Manda, 2002 (Jun 6) Glaucus atlanticus information. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/7151

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Re: Collaroy 'Blue Dragon' - thanks

May 23, 2002
From: Stephen Martin

Bill
Thanks for your timely response and info. Next time we will not pick them up. The kids were absolutely delighted to know that they feed on blue bottles.
Steve

smartin@sl.nsw.gov.au

Martin, S., 2002 (May 23) Re: Collaroy 'Blue Dragon' - thanks. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/7030

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Mass of blue dragon(?) nudibranchs

May 20, 2002
From: Stephen Martin

Late last summer at Collaroy swimming pool [Sydney, NSW, Australia] my sons and I found 18 nudibranchs (blue, black and silver). They appeared to be dead as we could pick them from the surface of the pool water. As we put them back over the pool wall they moved so may have been only stunned. (OR simply lethagic). It was a very overcast day, after rain and the tide was nearly full. Unfortunately there are storm water drains near the pool so I guess pollution cannot be ruled out. They may be blue dragons but I cannot confirm this from the reference books.
Any ideas ?
Steve

smartin@sl.nsw.gov.au

Martin, S., 2002 (May 20) Mass of blue dragon(?) nudibranchs. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/6999

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Questions about Glaucus

April 25, 2002
From: Luke Short

Dear Bill,
I am a lifeguard on the Sunshine Coast and lately we have been experiencing strong onshore winds. With these consistent winds of course, I have noticed many of these organisms being washed onto the beach- more often then not at the same time. Until I discovered this website I had been absolutely puzzled in regard to identifying what these creatures were and I basically knew nothing about them except whether or not they harmful to humans (such as the bluebottle Physalia physalis ). I have noticed that when I pick up a Glaucus or Glaucilla it leaves some blue part of its anatomy on my hand - they appear to be the cerata(?). Do you know why the organism does this? Another question I have regards the Purple Bubble-raft Snail (Janthina janthina ). When I provoked a floating snail, it appeared to emit a bright blue fluid into the water as some kind of defence mechanism. Is it possible for you to shed some light on this matter?

Thankyou for your time and also for such a great website. So many people ask me what these creatures are and up until now I have been substantially clueless!
Thankyou,
Luke.

lukeshort1979@hotmail.com

Short, L., 2002 (Apr 25) Questions about Glaucus. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/6718

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Blue plankton in Uruguay

February 16, 2002
From: Philip Miller

Recently there was a great arribada of blue plankton in our coast, in SW Atlantic ..... millions of Velella, hundreds of Physalia and Janthina, and less of Glaucus could be seen from Valizas to Santa Teresa .... would like to know about their ecology, specially their reaction to temperature and salinity changes, as well as their predator-prey relationship.

Philip Miller
FCIEN
Soriano 1510
Montevideo, 11200
Uruguay

maritimo@adinet.com.uy

Miller, P., 2002 (Feb 16) Blue plankton in Uruguay. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/6211

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Glaucus from Pensacola, Florida

February 4, 2002
From: Elvira Davis

Can you please help me identify this sea creature? It was found washed up on the shore of Pensacola Beach in NW Florida, USA just 2 days ago [30 Jan 2002]. Attached is a pretty pitiful sketch of it -- I'm no artist! It is about 1 inch long and there were many of them washed up on the shore along with many Portuguese man-of-wars. Thank you!
Elvira Davis

Stelda91@cs.com

Davis, E., 2002 (Feb 4) Glaucus from Pensacola, Florida. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/6171

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Re: Glaucus detecting prey

March 18, 2001
From: Belinda Biggam

Dear Bill
Many thanks for your reply re. nudibranchs detecting their prey - your information said pretty much what I have since been able to find out, so it's great to have this confirmed!

I would also like to say what a great find your Sea Slug Forum was for me - with so much junk on the internet it always makes my day to find something interesting, worthwhile and extremely useful.
Best wishes
Belinda Biggam

belindab@thefutureiswild.com

Biggam, B., 2001 (Mar 18) Re: Glaucus detecting prey. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/3992

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Glaucus detecting prey

March 15, 2001
From: Belinda Biggam

I am trying to find out how nudibranchs detect their prey. I am particularly interested in how Glaucus sp. detects and hunts down Physalia. I have trawled through numerous text books and searched the web but to no avail. Would you be able to enlighten me. Look forward to hearing from you ASAP - i'm a researcher in natural history tv and have got an urgent deadline to meet!!
Many thanks.
Belinda Biggam

belindab@thefutureiswild.com

Biggam, B., 2001 (Mar 15) Glaucus detecting prey. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/3891

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Re: Glaucus

February 20, 2001
From: Lisa

Hi
I just wanted to thank you all ... I have lived On the Eastern suburbs Beaches of Sydney, Australia all of my life. As a child I quite often saw these creatures [Glaucus] on the shore and usually when Bluebottles were around, but never knew what they were. Today while I was at the beach with my 10 year old son, He found one. Of course he wanted to know what it was .... and all I could say was "well I haven't seen one for a while, but I know its not a bluebottle" He was fasinated by it as I was when I was a kid.(about ten minutes later he got stung by a bluebottle as all good Aussie kids do) BUT NOW I CAN TELL HIM WHAT IT WAS and what's more after 25 years of wondering I KNOW !!!
Lisa

l_harper@dingoblue.net.au

Harper, L., 2001 (Feb 20) Re: Glaucus. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/3833

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Glaucus

August 24, 2000
From: Chris Parks

Fantastic site - Congratulations!
Very interesting section on Glaucus - which is one of my favourite animals! You might be interested to see some of our images of Glaucus. They can be seen at
http://www.imagequest3d.com/catalogue/surfacedrifters/index1.htm.

Regards,
Chris

chris@imagequest3d.com

Parks, C., 2000 (Aug 24) Glaucus. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/2910

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Information on Glaucus atlanticus

August 12, 1999
From: Angela

I am currently in first year at University and am preparing a talk about the Mollusc - Glaucus atlanticus. Although my talk is based on the Phylum Mollusca I'm using Glaucus as the example. I'm having trouble finding how it would react if it was disturbed. I have found some wonderful pictures and information on this website but would appreciate you're help in finding the answer to my question. I look forward to hearing from you.

Thanks
Angela

ronr@cdc.net.au

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Eggs of Glaucus and Glaucilla

May 16, 1999
From: Bill Rudman

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Glaucus & Porpita in New Zealand

March 31, 1999
From: Ross Armstrong

Hi Bill

I sent a copy of your comments off to Bill and Lynda West and they really appreciated the information you provided.

They have also sent me more information about the siphonophore they fed the Glaucus on and would like your thoughts on it:

"The siphonophore was slightly different to what Bill Rudman described.  It is a round flattened disc, with a wafer thin but very flexible transparent scale on its top.  Around the outer edge is a deep blue coloured mantle, which can be up to 2mm in width in the larger specimens.  On the under side of the mantle hang 4-5mm long polyps which look like miniature strings of bluish green beads when put against a white background."

"The underside of the main body of the siphonophore contained a mass of very small blue polyps, not long tentacles as mentioned and the centre polyps were white.  This white area was circular, ranging roughly from 0.5mm to 5mm on the large ones.  The pattern was the same on every specimen we found."

"Another thing we noted was that when one was placed on bare skin, i.e. the palm of a hand, it would cause the skin to itch in the area that came in contact with the polyps.  We wonder if this could have caused the itching
that many swimmers have complained about this summer."

Any ideas on what it is?  I have attached a photo they sent to me.

Kind regards

Ross Armstrong

Ross@northpower.co.nz

Armstrong, R., 1999 (Mar 31) Glaucus & Porpita in New Zealand. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/738

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Re: Glaucus in New Zealand

February 26, 1999
From: Ross Armstrong

Hi Bill
I read their letter again when I got home and it was me who got the id wrong. They had correctly identified it as Glaucus atlanticus and I had made the mistake in my earlier email. They had also done quite a bit of homework. The first one they found they kept with some Velella to use as food. Unfortunately the Velella died over night as did the Glaucus. They went searching after the next lot of easterlies and found some washed up. First they found some small round jellyfish ranging in size from a pin head to about 10mm across. The closest id they could get was Chondrophore. They found these jellyfish were the preferred food source for the Glaucus they kept. Another comment was that when the feed the Glaucus on a daily basis the mortality rate would climb and concluded that their feeding pattern is on a hit and miss basis.
Here is what they say about them feeding:
"Over the past four days we have watched them feeding. When they come in contact with the food source they wrap themsevles around it sideways and guide the food forward with their fronds (cerata) until they can clasp it with their front fronds. The will either pull the food over their head to eat, or will hang vertically under it while eating. The mouth, which is oval, is located at the front of the head and perhaps is similar to that of a lamprey and the creature will feed voraciously, as though this is this meal is the last it may have for sometime."

Other observations:
"We are unable to detect an anal duct. We think the slight protrusion on the left hand side may house both the anal duct and the reproductive organs as some of the creatures have an opaque white corkscrew like thing protruding from their and yesterday (19 Feb) we noted that two of the creatured seemed to be mating in a back to back position."
"We also noted that when placed in direct sunlight they turn upside down and then back again. Perhaps they are cooling themselves down as their backs are out of the water when they float about. In the sea the wave movement would possibly wash over them thus keeping them cool."
"We also tried using an aquarium pump to keep the water aerated, but this only caused more of them to die. Over-feeding them was also a headache as the death rate started to climb. We think this was due to the toxic nature of the food they ate and figured that they required more time between meals to aid with digestion. We now feed them ever other day."
At one stage they had a total of 38 (the figure of 27 was another mistake I made). Unfortunately a lot had died and they decided to release them:
"The decision has been made to release the survivors as we are unable to locate any more food for them. We took the survivors up to the river mouth and released them into the out going current. What we noticed was that when back in their natural habitat they folded their appendages and fronds back towards their body and stayed just under the surface, whereas in captivity they floated high in the water with their appendages and fronds extended outwards."
Another interesting comment:
"We noted that the waste produced by the Glaucus formed a fine cobweb the occupied the bottom half of the bowl and may be toxic to them. Hence the high death rate when we introduced the air pump."
This may actually be the short egg strings you mentioned.
"We noticed the very small Glaucus (1-2mm long) seemed to disappear overnight when there was a lack of food and also some of the smaller ones starting to loose some of their fronds. We came to the conclusion that Glaucus developed cannibalistic tendencies where there was a food shortage and the larger ones would eat the smaller ones."
Their finishing comment:
"These findings are not based on a scientific study of Glaucus atlanticus but are based on what we noted on a daily basis over the past week."

Personally I think they did an excellent job and I apologise for the inaccuracies of my first e-mail which I wrote without having the letter readily available.

Ross Armstrong

ross@northpower.co.nz

Armstrong, R., 1999 (Feb 26) Re: Glaucus in New Zealand. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/618

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Glaucus in New Zealand

February 25, 1999
From: Ross Armstrong

Dear Bill

The attached image was supplied by my Uncle and Aunty Bill and Lynda West of Opotiki in New Zealand's Bay of Plenty.  (Central east coast of the North Island). In late January they were walking on the beach and encountered some Glaucilla washed up on the shore.  At the time neither had seen these before and did not know what it was.  They took some samples and had it identified
as Glaucilla alanticus. There have been a lot of easterlies blowing things up on the beach.  After getting it identified they went looking for some more.  So far they have
found a total of 27.  They have tried keeping them in a small aquarium but have a fairly high mortality rate.  I believe the photo was taken in the aquarium.  Neither are marine biologists but they have made some interesting observations including seeing a pair mating?  and also suspecting they might
become cannibalistic if there is a shortage of food.  They have been feeding them on jellyfish that have also been washed up.  They sent me a letter explaining what they have done and observed but I left it at home.
I look forward to any information you may be able to provide or questions that you may have.

kind regards

Ross Armstrong

Ross@northpower.co.nz

Armstrong, R., 1999 (Feb 25) Glaucus in New Zealand. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/616

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