Sargassum robustum J. Agardh, 1889: 66–67, pl. XIX: figs. 6–10, nom. illeg. (lectotype locality: Swan River, Western Australia fide Millar & Kraft, 1994a: 30).—De Toni, 1895b: 28.— Lucas, 1909: 10.— Grunow, 1915 [1915–1916]: 355.
Sargassum vigorosum P. Silva.
INDIAN OCEAN DISTRIBUTION: Australia.
Note: Sargassum vigorosum is proposed as a substitute name for S. robustum J. Agardh, a later homonym of S. robustum Kuntze (1880: 217, fig. 24; type locality: Chatham Islands, New Zealand), a species not reported from the Indian Ocean.