Navicula cryptocephala has rostrate apices and an evenly rounded central area. Navicula exilis has somewhat larger valves with protracted apices and a larger rounded central area.

LM scalebar = 10 µm
Length Range
22-38 µm
Width Range
4.8-6.9 µm
Striae in 10 µm
14-18
Navicula lundii LM7
Navicula lundii LM6
Navicula lundii LM5
Navicula lundii LM4
Navicula lundii LM3
Navicula lundii LM2
Navicula lundii LM1
Navicula lundii LM7 Navicula lundii LM6 Navicula lundii LM5 Navicula lundii LM4 Navicula lundii LM3 Navicula lundii LM2 Navicula lundii LM1
Length Range
21-34 µm
Width Range
5.2-6.5 µm
Striae in 10 µm
15-17
Navicula cryptocephala LM4 Navicula cryptocephala LM6 Navicula cryptocephala LM2 Navicula cryptocephala LM7 Navicula cryptocephala LM5 Navicula cryptocephala LM1 Navicula cryptocephala LM3

Also compare to

Navicula exilis

Kütz. 1844