Compare

Cymbella affinis and Cymbella excisiformis have smaller valves, smaller length to width ratios, and a single stigma.

Cymbella parva has narrowly rounded, unprotracted apices and just a single stigma.

Cymbella affiniformis is smaller with narrower apices and two isolated stigmata.

LM scalebar = 10 µm
Cymbella Rumrichae 076101 Cymbella Rumrichae 4546 1 Cymbella Rumrichae 013601 Cymbella Rumrichae4 Cymbella Rumrichae 4546 2 Cymbella Rumrichae6 Cymbella Rumrichae 409901
Length Range
22.1-56.6 µm
Width Range
7.5-10.7 µm
Striae in 10 µm
10-12 at the valve center, up to 15 near the apices

Cymbella affinis

Kütz. 1844

Gs009123  Gc100325 9 Gs009123  Gc100325 7 Gs009123  Gc100325 6 Gs009123  Gc100325 10 Gs009123  Gc100325 5 Gs009123  Gc100325 3 Gs009123  Gc100325 8
Length Range
19-36 µm
Width Range
6.9-9.0 µm
Striae in 10 µm
9-12 in the center valve, 13-14 at the ends

Cymbella excisiformis

Krammer 2002

Cymbella excisiformis LM5 Cymbella excisiformis LM2 Cymbella excisiformis LM1 Cymbella excisiformis LM3 Cymbella excisiformis LM4 Cymbella excisifomis LM7 Cymbella excisifomis LM6
Length Range
24-34 µm
Width Range
6.1-7.1 µm
Striae in 10 µm
9-11 in the center valve, 12-16 at the ends

Cymbella affiniformis

Krammer 2002

Cymbella Affiniformis1 Cymbella Affiniformis2 Cymbella Affiniformis3 Cymbella Affiniformis4 Cymbella Affiniformis5 Cymbella Affiniformis6 Cymbella Affiniformis7
Length Range
22.9-33.0 µm
Width Range
7.2-9.2 µm
Striae in 10 µm
10-12 dorsal, 11-13 ventral near valve center

Cymbella parva

(W.Sm.) Kirchn. in Cohn 1878

Cymbella parva LM1 Cymbella parva LM2 Cymbella parva LM3 Cymbella parva LM4 Cymbella parva LM6 Cymbella parva LM7 Cymbella parva LM8
Length Range
24.5-41.2 µm
Width Range
6.9-8.9 µm
Striae in 10 µm
10-12 at the valve center, up to 14 near the apices