Campylorthis deflexa

Specimen on the Left is bought online, from Wisconsin Mifflin Platteville Formation.

Campylorthis deflexa is the middle one with Rostricellula minnesotensis Leftmost.

Oepikina minnesotensis is rightmost. The specimen on the right is the closest Minnesota mifflin Campylorthis deflexa like specimen that I could find.

It is darker color rock so its harder to see good textures but if you look closer toward the edge you can see where ribs are which makes it more coarse than the much more numerous Strophomena and Oepikina which are distinct characteristic in Twin Cities bed.