From the album: Platteville to Decorah formation Ordovician Twin Cities
Some orthid brachiopods, mainly Cincinnetina and Dinorthis along with several lookalikes tend to be found only in Upper Decorah Formation. Upper Decorah tend to overlaps with Galena Formation and Richmondian formation. That's why you can find some of the same orthid brachiopod species from Minnesota to Ohio to Kentucky.