Gomphonema nathorstii is wider.

LM scalebar = 10 µm
Length Range
26.1-45.6 µm
Width Range
6.0-7.2 at the valve center µm
Striae in 10 µm
9-13
Gomphonema distans LM1
Gomphonema distans LM2
Gomphonema distans LM3
Gomphonema distans LM4
Gomphonema distans LM5
Gomphonema distans LM6
Gomphonema distans LM7
Gomphonema distans LM1 Gomphonema distans LM2 Gomphonema distans LM3 Gomphonema distans LM4 Gomphonema distans LM5 Gomphonema distans LM6 Gomphonema distans LM7
Length Range
30.8-49.6 µm
Width Range
7.8-9.9 near head pole; 8.3-10.0 at the valve center µm
Striae in 10 µm
10-13
Gomphonema nathorstii LM1 Gomphonema nathorstii LM2 Gomphonema nathorstii LM3 Gomphonema nathorstii LM4 Gomphonema nathorstii LM5 Gomphonema nathorstii LM6 Gomphonema nathorstii LM7