Valve arcuate to slightly reniform
Slight constricted central area
Parallel striae, rounded at apices
Strongly capitate apices
Break in fibulae with 4-6 striae
heteropolar valves
clavate to rhombic, widest at mid-valve
valves tumid at center
valves gradually narrow
rounded headpole and footpole
one isolated pore present close to central striae