Compare

Gomphonema apuncto is more narrow and linear. Gomphonema christensenii has longer striae that extend into the axial area and a greater range of size. Gomphonema puiggarianum var. aequatorialis is larger, with a lower stria density.

LM scalebar = 10 µm
Gomphonema louisiananum LM1 Gomphonema louisiananum LM2 Gomphonema louisiananum LM3 Gomphonema louisiananum LM4 Gomphonema louisiananum LM5 Gomphonema louisiananum LM6 Gomphonema louisiananum LM7
Length Range
13.5-38.3 µm
Width Range
3.8-5.5 µm
Striae in 10 µm
11-12 at the valve center, 14-16 at the apices

Gomphonema apuncto

J.H.Wallace 1960

Gomphonema apuncto LM4 Gomphonema apuncto LM1 Gomphonema apuncto LM3 Gomphonema apuncto LM2 Gomphonema apuncto LM5
Length Range
21.0-30.7 µm
Width Range
3.0-4.1 µm
Striae in 10 µm
13-16

Gomphonema christenseni

R.L.Lowe and Kociolek 1984

Gomphonema christenseni LM2 Gomphonema christenseni LM5 Gomphonema christenseni LM6 4 53920  Gchristenseni Holo 5 53920  Gchristenseni2 6 53920  Gchristenseni2 7 53920  Gchristenseni2
Length Range
32.8-57.4 µm
Width Range
6.1-7.8 µm
Striae in 10 µm
13-16

Also compare to

Gomphonema puiggarianum var. aequatorialis

Cleve