References:
Van den Heuvel, H.M. (1991). Diatoms from el Golfo on Lanzarote (Canary Islands). Vieraea 20: 53-70, Pl.1, Fig. 5;
Description:
Valves linear-lanceolate with protracted subrostrate to rostrate ends. Dorsal margin convex, sometimes slightly flattened at the centre, ventral margin straight or slightly convex, sometimes inflated at the centre.
Raphe filiform with dorsally bend proximal and distal ends. Central pores of the raphe small, but visible under LM. Axial area narrow, linear more developed on the ventral side. Central area absent on the dorsal side, on the ventral side expanded and reaching the ventral margin. Dorsal transapical striae delicately punctuated (puncta more distinct than in Morph. 1 and 2), straight or slightly radiate at the centre, becoming stronger radiate towards the poles. Ventral striae short, visible under LM, but impossible to count due to their very dense structure
