References:
Patrick, R. & Reimer, C. W (1966). The Diatoms of the United States I. Monographs of the Academy of Natural Sciences of Philadelphia. Pennsylvania. pp. 394-395; 432-433 [pl.36:1]
Description:
Valve is triundulate with protracted, distinctly rostrate ends; undulations are short and abrupt, making the greater part of the valve margin concave; axial area is narrow, diminishing in width further near the central area and the ends; raphe is straight or slightly diagonal, narrowing near the central area and the ends, with proximal ends curving in opposite directions and distal ends becoming bifurcate; central area is diagonally to transversely elliptical; primary longitudinal band is submarginal; punctate striae are radiate, becoming convergent or oblique at the ends; length is 50-57µm, breadth at centre undulation is 12-14µm; striae count is 24 in 10µm (20-22 puncta in 10µm)