Nitzschia inconspicua has more pointed apices. Furthermore, the areolae of N. inconspicua are slightly larger and often can be resolvable with LM.

Nitzschia frustulum has lanceolate valves with subrostrate ends and a wider size range.

LM scalebar = 10 µm
Nitzschia soratensis LM5 Nitzschia soratensis LM1 Nitzschia soratensis LM2 Nitzschia soratensis LM6 Nitzschia soratensis LM3 Nitzschia soratensis LM4
Length Range
3-17 µm
Width Range
2.0-3.3 µm
Striae in 10 µm

Nitzschia innominata

Sovereign 1958

Innominata 009 Innominata 004Tif Innominata 003 Innominata 002 Innominata 006 Innominata 008
Length Range
6-14 µm
Width Range
2-3 µm
Striae in 10 µm

Also compare to

Nitzschia frustulum

(Kütz.) Grunow in Cleve and Grunow

BioData Reference
Krammer and Lange-Bertalot 2/2 Pl 68 Fig 1-8

Nitzschia abbreviata