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Matches genus Platyrachella in Fenton and Fenton (1924), possibly species alta or cyrtinaformis. Not sure current taxonomy.

@jbauer do you have any insight on this ID? Or know someone who might? Thanks!

Hi @patrick-hsieh & @smoran – I don’t think it is Cyrtospirifer, there isn’t a clear fold and sulcus like I would expect with that genus. It looks more similar to Platyrachella but again no fold and one valve appears to be pretty flat maybe a little concave? I am not sure it is a spiriferid, why were you thinking that? Maybe some context would help.

@smoran & @jbauer I think I meant genus Cyrtina, but I most likely accidentally selected Cyrtospirifer when I entered it into the classification wizard. The basis for selecting Cyrtina is the reference I have for this locality is The Stratigraphy and Fauna of the Hackberry Stage of the Upper Devonian by Fenton and Fenton, 1924. In this publication. there are 2 genera that have a pyramidal shaped cardinal area, Platyrachella and Cyrtina. I selected Cyrtina at first as the description indicates the shell is “wider than long with the greatest width along the hinge-line” and the pedicle valve with the apex erect or moderately curved. The brachial valve is also slightly convex, which is consistent with the description. Looking at the pictures again, it does look closer to Platyrachella as the costae seem to be denser in that genus than in Cyrtina but I’m not sure how diagnostic that is, hence the queried genus.

Ah, @patrick-hsieh. Cyrtina makes more sense! Yeah, there are some minor things on your specimen that don’t seem to match any of the genera super well. Sometimes there are just weird forms! I think the diagnostic utility of costae can vary between different brachiopod groups X.x