Description:
Valve crescentic to arcuate with acutely rounded poles, 64.7-161.4µm long, 10-20µm broad. Dorsal margin smoothly curved sometimes more or less elevated at the middle part of the valve. Mid-ventral margin slightly concave to indented, becoming straight or gently bulged near apices. Raphe located close to the ventral margin, undulated. Proximal ends of the raphe oriented dorsally, distal ends strongly hooked towards the dorsal side. Central pores hardly visible under LM. Axial area developed dorsally, on the ventral side scarcely visible. Central area on the dorsal side large, formed as a result of shortening of the dorsal striae, on the ventral side small by reaching the ventral margin because of lack of the ventral striae at the centre. Dorsal striae more or less parallel in the middle part of the valve, becoming slightly radiate towards the ends, 9-12 in 10µm. Ventral striae very short, dash-like, lacking at the centre, 9-13 in 10µm.
