This Atrypa sp. brachiopod is from Benton County, Tennessee. It existed in the Lower Devonian Period and was found in the Birdsong Formation. The inarticulate brachiopod was called Ptylodictya tennis (circled in black).
Thanks to Herb for providing the specimen.
This is a view of the other side of the Atrypa sp. brachiopod. It looks like part of the shell surface was coated with a bryozoan.