Brachiopod IDs from Jack county, TX

[KimTexan]

I found these today in Jack county, TX not far from the Wise county border. I’m not sure what the formation is there, but I think it could be either Jasper Creek or Alluvium. I don’t know much about the Alluvium, which is Cenozoic, Quaternary. I’m not sure I’ve ever hunted in the Cenozoic so I’m not sure what would characterize it. I’m learning though. I’d say the material resembled Pensylvania. 

Pic 1 & 2 are side the 2 sides

I’m guessing that pic 1 is the dorsal valve side (there’s a convex vertical part running down the middle of the shell).

# 2 is the pedical valve side and there’s a concave vertical part running down the middle of the shell. But I could be wrong on which is which.

[KimTexan]

 

The third brachiopod above is fused with a 4th you can’t really see. They’re both partials.

 

The hinge view.

This is another variety I found at the same place. I had 2, but I think I just have dropped the 2nd one. It was white and slightly bigger.

This one is right at 2 cm.

[DPS Ammonite]

Neospirifer, common in North Texas Pennsylvanian marine rocks, looks similiar. See these photos:

and

http://www.northtexasfossils.com/fieldtrips/2008-03-09/03-09-2008-012-800.jpg

[bone2stone]

Yours is in better shape than the ones my wife and I found.

I agree Neospirifer....

[westcoast]

Really nice collection of spiriferid brachiopods

[Miocene_Mason]

I agree as well, the alluvium was formed in the Cenozoic, which means the river eroded off nearby rocks and covered them with sediment, hence Pennsylvanian fossils. 

[KimTexan]

 I need to go back to that place. I stopped on the drive home and spent less than 10 min there. Pennsylvania fossils are pretty new and different to me. I’ve mostly hunted in the Cretaceous. I hunted one other time in the Pennsylvania.

So I guess you’re saying they are both the same genus? I assume they’re different species though.

Thanks for the ID and comments.