Sargassum cymosum C. Agardh var. gueinzii Grunow, 1916 [1915–1916]: 140–141 (syntype localities: South Africa: Algoa Bay, Cape Province and Port Natal [Durban]).
INDIAN OCEAN DISTRIBUTION: South Africa.
Note: Papenfuss (notes) examined three sheets in Harvey's herbarium (in TCD) collected by Gueinzius at Port Natal and annotated as Sargassum lendigerum var. gueinzii by Grunow. They all appeared to him to be representative of S. elegans Suhr.