Valves linear to linear-elliptic, with subrostrate apices
Raphe valve with asymmetric fascia
Terminal raphe fissures turned to opposite sides
Valves are linear to linear-elliptic with subrostrate apices. The raphe valve has a fascia. The fascia is typically asymmetric. Terminal raphe fissures are turned toward opposite sides. Striae are biseriate, 18-24 in 10 µm.