Compare

Gomphonema duplipunctatum may be distinguished from G. parvulum and other small species of Gomphonema by its rhombic-lanceolate valves, unprotracted apices, and the two isolated stigmoids in the central area. Gomphonema germainii is similar outline and stria density but differs by having a single stigmoid. Gomphonema signyensis also has two stigmoids and overlaps in size, but differs in valve outline.


LM scalebar = 10 µm
Gomphonema Bipunctatum 1 470001 Gomphonema Bipunctatum 2 438801 Gomphonema Bipunctatum 3 405501 Gomphonema Bipunctatum 4 438001 Gomphonema Bipunctatum 5 503501
Length Range
18.6-34.5 µm
Width Range
4.8-6.3 µm
Striae in 10 µm
9-14

Gomphonema germainii

Kociolek and Stoermer 1990

Gogermanii 1301 44 4 Gogermanii 1166 39 8 Gogermanii 1164 39 7 Gogermanii 945 32 3 Gogermanii 804 27 4 Gogermanii 732 24 9
Length Range
24.7-43.8 µm
Width Range
4.6-6.3 µm
Striae in 10 µm
10-12 at the valve center, 12-14 at the headpole, 14-15 at the footpole

Also compare to

Gomphonema parvulum

BioData Reference
Krammer and Lange-Bertalot 2/4 Pl 76 Fig 1-7

Gomphonema signyensis

Kociolek and Jones