echinocnchid brachiopod

[Chris finner]

My son and I get a lot of clams from castleton, UK but I’ve never seen anything quite like this… any ID would be fantastic. 
 

thanks

[abyssunder]

In my opinion, there are two brachiopods attached. (Maybe the spines are gone?)

[Misha]

I don't think this is two brachiopods, to me it looks a lot more like one large brachiopod which was crushed and is missing a chunk from the middle of the shell closer to the hinge line. You can see where the missing portion is as it exposes the calcite crystal filled inside.

 

I'm not too good with Carboniferous brachs, @Tidgy's Dad may be able to say more, especially on the actual ID of the organism.

Edited May 9, 2022 by Misha

[abyssunder]

1 minute ago, Misha said:

I don't think this is two brachiopods, to me it looks a lot more like one large brachiopod which was crushed and is missing a chunk from the middle of the shell.

Not good with Carboniferous brachs, @Tidgy's Dad may be able to say more, especially on the actual ID of the brach.

So, in your opinion is a brachiopod and not a bivalve?

[Misha]

12 minutes ago, abyssunder said:

So, in your opinion is a brachiopod and not a bivalve?

I believe it is a productive brachiopod.

 

If it were more complete I believe it may look a bit more like this:

 

[Tidgy's Dad]

When I first saw this, I thought @abyssunder was correct and this showed two specimens on top of each other, but; on closer inspection, I now believe that @Misha is most certainly correct and that this is just the remains of one large productid brachiopod. 

There are at least fifty species of productid known from the area and about forty of them  are productoids, so it's pretty difficult to narrow that down without some extensive research. Size may help to reduce this number significantly and so Echinoconchus is a possibility, though there are at least three species of this. 

Edited May 13, 2022 by Tidgy's Dad

[Chris finner]

Thanks you everyone for looking I will let me son know