14 replies to this topic

[indigo]

Dear Wetpixel Chums,

Please would you be able to help me ID this? I have looked in the Paul and Ned book, to no avail.

Picture taken in St. Vincent, 29th Nov - in about 15 ft of water. I have only seen these twice before, and would like to put a name to them!

Thanks for your help!

Kay
St. Vincent.

PS Can anyone let me have US$5700 so that I can go on the Sardine Run this year!

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[Leslie]

Sure it's a critter, or rather a group of them. Some kind of anemone or coralliamorph. William or another cnidariphile should be able to give you a more precise answer.

[james]

Actinodiscus maybe? Wow, I thought Ricordia were the only corraliamorphs in the carib. Cool.

Cheers
James

[Giles]

James here in Cayman .. and probably elsewhere there are loads of Pseudocorynactis caribbeorum in many different colours.

oh how our small sea is underestimated ..

james wouldn't your guess make it a coral ?

[acroporas]

It is Warty Corallimorph Discosoma sanctithomae

[acroporas]

Actinodiscus maybe? Wow, I thought Ricordia were the only corraliamorphs in the carib. Cool.

Cheers
James

James here in Cayman .. and probably elsewhere there are loads of Pseudocorynactis caribbeorum in many different colours.

oh how our small sea is underestimated ..

james wouldn't your guess make it a coral ?

In addition to Ricordea, the Species pictured above, and Pseudocorynactis which Giles mentioned, there are at least 3 other species of caribbean Corallimophs.

Check out this one....http://sealifeinc.net/catalog/product_info.php?cPath=28&products_id=138

[Giles]

I have a question .. what is the difference between a Corallimorph and a an Anemone ?

[acroporas]

Well if you really want to get into it, lets start at the top. I've highlighted the tree to corallimorphs.

Phylum Cnidaria

Within Cnidaria you have 3 basic groups
_________________________________
Corals - Class Anthozoa
Hydroids - Class Hydrozoa
Jellyfish - Scyphozoa, Cubozoa, and Staurozoa


Class Anthozoa then splits into two:
___________________________________
SubClass Alcyonaria which has 8 way symmetry (soft corals)
SubClass Zoantharia which has 6 way symmetry (hard corals, anemones, and various "polyps")



Zoantharia is split up into many orders a few noteworthy ones are:
___________________________________________
Scleractinia (Stony Corals / Hard Corals)
Actiniaria (Anemones)
Corallimorpharia (what we are talking about)





So you see, Corallimorphs are no more related to anemones than they are to hard corals. They look very similar to anemones to real people, but to scientists there is no mistaking them.

As far was what the scientists are looking at that makes them so different. I don't know exactly, but I'd bet that even if I did know the exact details, it would not really help you distinguish them visually, ( their insides work a bit differently ) and would require lots of big words that no one other than the scientists understand anyway.




From a practical standpoint: Corallimorphs tend to be smaller and have short tentacles.

[Giles]

Wow .. remarkably well explained .. I think I kinda understand .. and thanks for the practical standpoint too !

[Leslie]

You can think of coralimorphs as the love child between anemones & corals. The internal organization is identical to corals but they lack the calcium skeleton. They're commonly flat and the tentacles are short, arranged in lines radiating out from the mouth (which is usually an "outie" instead of an "innie") and which tend to form concentric circles.

[indigo]

Dear Wet Pixel Chums,

Thank you so much for your help once again! I spend so much time in the water around St. Vincent that it has become difficult for me to appreciate how much life that we see here is unusual elsewhere. However when I spot something that I have not seen before, or very rarely see, it's a treat. And then when it's something that I cant find in the books that I have in the shop - well then I get really excited. (People that live on very small islands far away from 'civilization' excite very easily!

Annnyway I have learned so much from this site, and from the folks in Wet Pixel land. Thanks again!

Kay Wilson
Indigo Dive,
St. Vincent.

PS No joy with the donation for the Sardine Run....? I'll just have to keep saving my pennies

[LekicINC]

I made a mistake on my first post, thinking they were closely related to soft corals. Anyway, is zoantharia the same thing as hexacorallia? If no, whats the difference?

Edited by LekicINC, 01 December 2007 - 03:15 PM.

[Leslie]

is zoantharia the same thing as hexacorallia? If no, whats the difference?

Yes, they're alternative names for the subclass.

[IMSushi]

So, William or Leslie, where do Gorgonians fit into your tree? ie. Genus Muricea, Lophogorgia. They are not true hard corals, nor are they soft. Are they corals at all?

I don't mean to take the discussion off topic, but it seems an appropriate place for the question...if you don't mind.

[Leslie]

Gorgonians belong to Alcyonaria - the "octocorals". They're not corals but belong in the same group because they all have 8 pinnate tentacles per polyp, members of Zoantharia all have 6 internal septa (membranes) - the 6-way and 8-way symmetry Will mentioned. Here's a couple of pages with more information:
http://www.tolweb.org/Anthozoa/17634
http://web.archive.o.../wb/default.asp