A very large complete, biconvex specimen with both valves showing the concentric growth lamellae. It is almost the maximum size for the species. The permesothyridid foramen shows the pedical collar; the delthyrium is also visible. Anteriorly the valves are slightly biplicate and the commissure is paraplicate. From Orford, Suffolk, UK.
Size: 102mm x 74mm x 54mm
Size: 102mm x 74mm x 54mm