Gomphonema truncatum is more narrow.

Gomphonema pala is similar in valve shape, but has biseriate striae.

Gomphonema italicum differs in the shape of the headpole; the headpole is not pointed at the apex and is more constricted just below the headpole.

Gomphonema laticollum is more linear in valve outline.

LM scalebar = 10 µm
Gomp Turg 15670B 12072015 Cl Gomp Turg 15544A 09172015 25 Cl Gomp Turg 15670B 12072015 03 Cl Gomphonema turgidum LM3 Gomphonema turgidum LM2 Gomp Turg 15596A 09042015 33 Cl Gomp Turg 15670B 12072015 04 Cl
Length Range
30-49 µm
Width Range
11.3-15.0 µm
Striae in 10 µm

Gomphonema truncatum

Ehrenb. 1832

Gomphonema Truncatum 001 Gomphonema Truncatum 003 Gomphonema Truncatum 002 Gomphonema Truncatum 005
Length Range
30-60 µm
Width Range
9-10 µm
Striae in 10 µm

Also compare to

Gomphonema pala

E.Reichardt 2001

Gomphonema italicum

Kütz. 1844

Gomphonema laticollum

E.Reichardt 2001