Eunotia naegelii is more narrow and has a greater stria density than E. bilunaris and E. flexuosa.

LM scalebar = 10 µm
Length Range
42-180 µm
Width Range
2.5-3.5 µm
Striae in 10 µm
14-17 in the center, 16-22 at the ends
Eunotia Naegelii Long I
Eunotia Naegelii Long Ii
Eunotia Naegelii Long Iii
Eunotia Naegelii Mid
Eunotia Naegelii Girdle
Eunotia Naegelii Short Ii
Eunotia Naegelii Short
Eunotia Naegelii Long I Eunotia Naegelii Long Ii Eunotia Naegelii Long Iii Eunotia Naegelii Mid Eunotia Naegelii Girdle Eunotia Naegelii Short Ii Eunotia Naegelii Short

Eunotia bilunaris

(Ehrenb.) Schaarschm. 1881

Length Range
33–110 µm
Width Range
3.1–4.7 µm
Striae in 10 µm
11–16 at center of the valve, 15–19 near the apices
Eu Bilun 1 Eubilun 8 Eu Bilun 3 Eu Bilun 4 Eu Bilun 5 Eu Bilun 6 Eu Bilun 7

Also compare to

Eunotia flexuosa

(Bréb. in Kütz.) Kütz.