Compare

The apices of F. soror are slightly constricted as compared to the capitate or subcapitate apices of F. capitata. The ventral longitudinal rib of F. soror is complete, unlike that found in F. latita. The longitudinal ribs of F. weinholdii are incomplete on both sides of the valve, and it has a lower stria density (30-33 in 10 ┬Ám).

LM scalebar = 10 µm
Frustulia soror LM6 Frustulia soror LM5 Frustulia soror LM4 Frustulia soror LM3 Frustulia soror LM2 Frustulia soror LM1
Length Range
28.5-52.0 µm
Width Range
7.5-9.5 µm
Striae in 10 µm
34-36 at the center, 35-37 at the ends

Frustulia creuzburgensis

(Krasske) Hust. 1957

Frustulia creuzburgensis LM7 Frustulia creuzburgensis LM4 Frustulia creuzburgensis LM1 Frustulia creuzburgensis LM3 Frustulia creuzburgensis LM6 Frustulia creuzburgensis LM5 Frustulia creuzburgensis LM2
Length Range
26.0-38.0 µm
Width Range
6.0-8.0 µm
Striae in 10 µm
24-26 at the center, 28-30 at the ends

Frustulia latita

Graeff and Kociolek 2011

Frustulia latita LM1 Frustulia latita LM2 Frustulia latita LM3 Frustulia latita LM3 Frustulia latita LM5
Length Range
32.0-48.0 µm
Width Range
8.0-10.0 µm
Striae in 10 µm
30-32 at the center, 33-35 at the ends

Frustulia capitata

Graeff and Kociolek 2011

Fragilara capitata LM1 Fragilara capitata LM2 Fragilara capitata LM3 Fragilara capitata LM4 Fragilara capitata LM5
Length Range
26.0-43.0 µm
Width Range
7.0-8.5 µm
Striae in 10 µm
34-36 at the center, 35-38 at the ends

Also compare to

Frustulia weinholdii

Hust.

BioData Reference
Lange-Bertalot 2001 Pl 133 Fig 5-7