Gomphonema dichotomum striae are not punctate.
Morphotype 1 valves have acutely rounded apices, more tapered footpole, and just over 30 μm to 100 μm in length (Morales 2001).
Morphotype 2 valves have the same characteristics as morphotype 1, but with greater curvature of the dorsal valve (Morales 2001).
BioData Reference
Krammer and Lange-Bertalot 2/4 Pl 84 Fig 4-8
BioData Reference
Kociolek and Stoermer 1991 Fig 30-37