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I think the two large brachiopod, one in NW corner and one SE corner is maybe new to me. The muscle ridges are very different with two parallel to each other extending from hinge line. Also seem like Upper Decorah Formation tend to have more varieties of Strophomenid brachiopods that is rarer in Middle and Lower Decorah Formation. One new thing I just learned today is Sowerbyella minnesotensis tend to be very variable in #  from site to site. It is very characterized of Upper Decorah Formation as well too, being entirely absent from Middle and Lower Decorah Formation. One site had Sowerbyella minnesotensis making up vast majority of shell hash while yesterday site where I collected most of the fossils have Sowerbyella minnesotensis in low densities.