The rostroconch was at one time classified as a Pelecypoda but now have their own class as Rostroconchia. The section in the book only covered 4 pages so I am guessing these creatures are somewhat rare and not studied a great deal. The geologist that wrote the section was named Richard D. Hoare who was a professor at Bowling Green State University in Ohio from 1957-1990.
My cousin found this fossil and it appears he may have cleaned it with an air abrasive cleaner.
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