Compare

Gomphonema pygmaeum has a linear-clavate valve and rounded apices. Gomphonema chinense has a broad axial area and narrow footpole. Gomphonema subtile has larger valves that are more strongly heteropolar. Gomphonema parvulum has a linear-clavate shape and less protracted apices.

LM scalebar = 10 µm
Gomphonema superiorense LM1 Gomphonema superiorense LM3 Gomphonema superiorense LM2 Gomphonema superiorense LM5 Gomphonema superiorense LM4 Gomphonema superiorense LM6 Gomphonema superiorense LM7
Length Range
23.2-26 µm
Width Range
3.6-4.2 µm
Striae in 10 µm
13-14 in the valve center, 15-16 at the headpole, 14-15 at the footpole

Gomphonema pygmaeum

Kociolek and Stoermer 1991

G Pygmaeum 111316A 005Rev G Pygmaeum 111316A 004Rev G Pygmaeum 111316A 001Rev G Pygmaeum 111361 008Rev G Pygmaeum 111316A 003Rev
Length Range
10-40 µm
Width Range
3-5 µm
Striae in 10 µm
10-13 in the center, 14-16 at the footpole

Also compare to

Gomphonema chinense

Liu and Kociolek

Gomphonema subtile

Ehrenb.

Gomphonema parvulum

(Kütz.) Kütz.