Geissleria ignota is similar in size to G. paludosa, but G. ignota has triundulate valves.

LM scalebar = 10 µm
Length Range
16-18 µm
Width Range
3.0-3.2 µm
Striae in 10 µm
15-16
Geissleria ignota LM6
Geissleria ignota LM5
Geissleria ignota LM2
Geissleria ignota LM3
Geissleria ignota LM4
Geissleria ignota LM1
Geissleria ignota LM6 Geissleria ignota LM5 Geissleria ignota LM2 Geissleria ignota LM3 Geissleria ignota LM4 Geissleria ignota LM1

Also compare to

Geissleria paludosa

(Hust.) Lange-Bert. and Metzeltin