Pennsylvanian Brachiopods and Possible Bivalve

[REW01]

I have some brachs I recently collected just outside of Swissvale, CO. I believe I have a some Rynchonelida, Strofomenida, Orthida, and possibly some poorly preserved that could be spiriferids though I'm not really sure. Although I can identify them to the level of order, I have no reference for brachiopods in my meagre library so I'm hoping someone here may be able to help out. I'd like to maybe identify some to better than order.

 

The formations in the area of this age are the Belden and Minturn fmts, I don't know which the fossiliferous mudstone these came out of belongs to. It's very fossiliferous. I also saw some chunks of what looked like a limestone with fossils, though they were too large to collect. I still have a bag of loose matrix to sort through for small fossils. These are just the little ones, and loose brachs I found already eroded out. I have some more larger ones waiting to see a little prep.

 

The entirety of the tiny collection, including partial brachs and my few token crinoid columnals below. 

 

[REW01]

Group 1: possible Orthida

 

[REW01]

Group 2: Rynchonelida (?)

 

[REW01]

Group 3: Orthida (?) and the third photo, maybe spiriferids? They are all incomplete, but seem to show a strong sulcus, which makes me think spiriferid. I have a couple that appear to be the same kind and complete that need prep.

 

[REW01]

And the mystery shell:

 

[DPS Ammonite]

 

 

It looks like possible the gastropod, Bellerophon. Better close up photos and photos looking at the aperture head on will help us.

 

https://www.digitalatlasofancientlife.org/learn/mollusca/gastropoda/paleozoic-gastropods/

[FossilDAWG]

A relevant publication would be:

P.K. Sutherland & F.H. Harlow (1973).  Pennsylvanian Brachiopods and Biostratigraphy in Southern Sangre de Cristo Mountains, New Mexico.  New Mexico Bureau of Mines and Mineral Resources Memoir 27.  The fossils covered in this publication occur widely in northern New Mexico and in Colorado.  It should be very useful in getting your brachiopods to genus and likely to species.  I think it is still in print, at least I ordered a copy just a few years ago.

 

Don