Pentamerida?

[Rosemary]

This sample is little more than a couple of centimeters. I was wondering if it's a brachiopod and if so, is it a pentamerida? 

[Misha]

Definitely a brachiopod,

It does look like a pentamerid,

But I am no expert in brachiopods, not yet anyway.

[Tidgy's Dad]

Looks more like an orthid to me, maybe an atrypid. 

In pentamerids the 'groove' on the internal mold is usually much broader and more obvious at the pedicle and does not usually continue to the anterior margin. 

The tooth sockets look very orthid, but I could be wrong. 

[Mark Kmiecik]

I would like to compliment your photography skills. Nice specimen.

[Rosemary]

Thank you, Mark, for the photo shout out. I appreciate that.

 

My guess of this being pentamerida came from the following link in which the groove extends the length of the bpod, as well as seeming similarities in the area around the medial septum.

http://www.fossilplot.org/GlossaryFiles/helpmain_glossary_brachiopoda_pentamerida.html

[Tidgy's Dad]

I don't think this is a pentamerid medial septum. As I say, the groove would be wider at one end as well as probably a lot deeper as the whole valve should be split in half at least at the posterior end. 

And the 'tooth sockets' or molds of where the teeth were isn't like a pentamerid at all. I don't think they ever had teeth but were closed by strong muscles attached to the spondylium. Also the hinge line  seems too wide to me. 

Just my opinion. 

@Peat Burns, I'd be interested to know your opinion, old chap? 

 

 

 

[Rosemary]

Thank you for those important details!

[Peat Burns]

On 5/21/2019 at 11:46 PM, Tidgy's Dad said:

I don't think this is a pentamerid medial septum. As I say, the groove would be wider at one end as well as probably a lot deeper as the whole valve should be split in half at least at the posterior end. 

And the 'tooth sockets' or molds of where the teeth were isn't like a pentamerid at all. I don't think they ever had teeth but were closed by strong muscles attached to the spondylium. Also the hinge line  seems too wide to me. 

Just my opinion. 

@Peat Burns, I'd be interested to know your opinion, old chap? 

 

 

 

That seems a very reasonable argument to me, Adam .