Compare

Navicula aurora has a transversely rectangular central area and striae that are parallel to slightly convergent at the apices. Navicula volcanica has larger rhombic valves with rounded, rather than protracted apices.

LM scalebar = 10 µm
Navicula ludloviana LM4 Navicula ludloviana LM1 Navicula ludloviana LM6 Navicula ludloviana LM5 Navicula ludloviana LM2 Navicula ludloviana LM3 Navicula ludloviana LM7
Length Range
63-163 µm
Width Range
20-33 µm
Striae in 10 µm
6-9

Navicula aurora

Sovereign 1958

Navicula aurora LM6 Navicula aurora LM1 Navicula aurora LM2 Navicula aurora LM3 Navicula aurora LM4 Navicula aurora LM5
Length Range
65-130 µm
Width Range
18-28 µm
Striae in 10 µm
7-9

Navicula volcanica

L.L.Bahls and Potapova 2015

Navicula ludloviana LM1 Navicula ludloviana LM2 Navicula ludloviana LM3 Navicula ludloviana LM4 Navicula ludloviana LM5
Length Range
100-176 µm
Width Range
30-37 µm
Striae in 10 µm
6 in the center of the valve, 8 at the ends