Gomphonema olivaceum f. stauroneiformis Grunow 1880
Homotypic synonym according to GBIF classification (Originally found in sources as accepted taxon within Gomphonema olivaceum (Lyngbye) Desmazieres)
Gomphonema quadripunctatum f. tumida Skvortzow & Meyer 1928
Homotypic synonym according to GBIF classification (Originally found in sources as accepted taxon within Gomphonema quadripunctatum Skabichevskii, 1985)
Gomphonema staurophorum var. oblongum Li & Shi 2003
Homotypic synonym according to GBIF classification (Originally found in sources as accepted taxon within Gomphonema staurophorum (Pantocsek) Cleve-Euler, 1955)
Homotypic synonym according to GBIF classification (Originally found in sources as accepted taxon within Gomphonema C.G.Ehrenberg, 1832)
Gomphosinica geitleri (Kociolek & Stoermer) Kociolek, You & X. Wang 2015
Homotypic synonym according to GBIF classification (Originally found in sources as accepted taxon within Gomphosinica Kociolek, You, X.Wang & Q.Liu, 2015)
