Feather duster worm ID (Cyprus)

Dear experts!

In Cyprus bays is this feather duster worm very common but I found no matching records so far. For me it looks like Sabellstarte sp. and being an Lessepsian immigrant. But as I wrote I was not able to find any information but perhaps I am wrong and it is something else and I was looking in the wrong place.

Just an observation: When during summer the water temperature in shallow bays exceeds about 32 degree on the Celsius scale then you may observe (during night) that the worm leaves it tube and starts to swim like a jellyfish into deeper, colder and better circulated water where it settles again.

PS.: I can provide more pictures for details if necessary.

Welcome to Wetpixel!

This is one of the few genera of fanworms that are easy to identify if the images show the right details and fortunately your second one does. See the little filaments on the outside of the feathery crown? The only genus that has these is Branchiomma. About 7 species are reported from Italy & adjacent areas, some native & some introduced.

Your observation about the worms moving in response to environmental changes is quite interesting. I've noticed that they will rapidly leave their tubes & swim away when disturbed but I don't think anyone has reported this type of migration. Can you tell if they are releasing eggs & sperm as they move?

thanks for posting--

Leslie

Your observation about the worms moving in response to environmental changes is quite interesting. I've noticed that they will rapidly leave their tubes & swim away when disturbed but I don't think anyone has reported this type of migration. Can you tell if they are releasing eggs & sperm as they move?

Firs to answer your question: No, I did not notice any release of eggs and/or sperm. But what I did was that I marked the place where one or the other of these worms settled after their swimming exercise just to find them again during daylight where they then rebuild their tubes in a couple of days.

One more observation of movement: I was able to notice in an aquarium that one of the worms climbed up the hose from the sump some 40 cm into the main tank.

By the way meanwhile I checked the EU MarBEF taxon database for European waters and there I found the following recorded list:

Branchiomma bahusiense Johansson, 1927

Branchiomma boholense (Grube, 1878)

Branchiomma bombyx (Dalyell, 1853)

Branchiomma inconspicua (M. Sars in G.O. Sars, 1872)

Branchiomma infarctum (Krøyer, 1856)

Branchiomma luctuosum (Grube, 1869)

Branchiomma lucullanum (Delle Chiaje in Quatrefages, 1866)

Branchiomma moebii Knight-Jones, 1994

Branchiomma spongiarum Knight-Jones, 1994

Branchiomma vesiculosum (Montagu, 1815)

The only one I know for sure that does not fit is Branchiomma vesiculosum (Montagu, 1815) syn. for Megalomma vesiculosum (Montagu, 1815). But for this worm an other question arises for me: It seems that in Cyprus waters where it is quite common do exist several color variations of this species. Of course I have pictures.

And at the end thank You for welcoming me. I read this site for quite some time before I took my hart as a non native speaker of English and enrolled.

--

Helmut Carl Simak

I'm, glad you joined. Anyone who posts polychaete pictures is my new best friend!

Do you have images of them swimming? I've spoken to 2 colleagues who specialize on fan worms & neither of them have ever heard of Branchiomma leaving the tubes except in response to habitat disturbance or predation. There are no reports of them emerging from the tubes to spawn either. So they are very curious about this behavior.

Small sabellid species are much more mobile than the large ones. They can swim better & it's easier for them to rebuild tubes.

Not all of the species on the list will make it into the Mediterranean. B. spongiarum, for example, is a cold water species described from the Faroe Islands.

Another species newly described for the area is Branchiomma maerli -

Licciano & Giangrande 2008 - the genus Branchiomma in the Mediterranean with the description of B. maerli

http://scientiamarina.revistas.csic.es/ind...viewArticle/940

Branchiomma bairdi is a newly recognized introduced species in the Mediterranean. It originated in the Caribbean

http://www.informaworld.com/smpp/content~c...ll~jumptype=rss

Color is not always a good way to identify polychaetes. There are some species in which the color pattern is absolutely unique while in others it may be quite variable. A striking example is the christmas tree worm which can be red, white, yellow, blue, green, orange, brown, or even a mix. It always takes specimen examination to be really sure of the species ID.

Cheers, L

I'm, glad you joined. Anyone who posts polychaete pictures is my new best friend!

 

Do you have images of them swimming? I've spoken to 2 colleagues who specialize on fan worms & neither of them have ever heard of Branchiomma leaving the tubes except in response to habitat disturbance or predation. There are no reports of them emerging from the tubes to spawn either. So they are very curious about this behavior.

First sorry for the long delay in answering Your question, Leslie. Unfortunately it did not work out to fix this special moment with at least one picture. The problem was that I always lost focus on the worm with my camera in one and the torch in the other hand while snorkeling during night and the waves washing in. Even when the worm stands still my Canon G9 has troubles to put the focus right in place. I was quite sorry then because it was quite clear for me that I probably saw something (very) uncommon.

Meanwhile I read all Your suggested articles and it looks like for me that there are probably two different species of Branchiomma around with Branchiomma bairdi as the closest match for at least some of my pictures.

I added two more pictures which show clearly the different style of the worms in Cyprus Waters. (I know about color variations but but both styles are quite distinct and can be found across the isle.)

And Yes, I already booked again for Cyprus at the end of November for two more weeks.