References:
Krammer K. & Lange-Bertalot H. (1991): "Susswaserflora von Mitteleuropa", Vol.4, pg.86, Taf.51:1-5;
Description:
Valve is elliptical to somewhat linear-elliptical; intercalary band with rudimentary short extensions into axial cavity often in evidence; raphe valve has very narrow axial area, small (more or less oval) central area, filiform raphe (with close proximal ends and straight distal ends terminating at inner hyaline ring), radiately curved finely punctate striae (which are interrupted at the margin by a hyaline area), and short, striate submarginal area encircled by hyaline area; pseudoraphe valve has very narrow, linear pseudoraphe, faintly distinguished central area, finely punctate radiate striae (punctae form many close undulate longitudinal rows); length is 10-70µm, breadth is 8-40µm; striae count is 20-23 in 10µm (RV), 24-26 in 10µm (PRV); Krammer & Lange-Bertalot (1991) describe the araphid valve as having a linear axial area with radial punctate striae (18-22 punctae in 10µm); striae count is 20-23 in 10µm (raphid valve) and 24-26 in 10µm (araphid valve)
