A fine complete typical example for this important species. It is slightly larger larger than the average sample with both valves. It shows the typical outline, flat ventral valve, high uniplication, sharp dorsal fold and two costae on either side of the fold. The linguiform extension is long and sharply trigonal. It differs from JBR 10.0 in the presence of faint radial striae, a shallower sulcus and its smaller size.
Size: 11 mm x 14 mm x 13 mm
Size: 11 mm x 14 mm x 13 mm