Sargassum distichum Sonder, 1845: 51 (type locality: Western Australia).—J. Agardh, 1848b: 348.— Sonder, 1848 [1846–1848]: 162.— Harvey, 1863: vi.— Sonder, 1880: 2.— Grunow, 1915 [1915–1916]: 417.— Womersley, 1987: 444–446.— Huisman & Walker, 1990: 384.— Kendrick, 1993: 460.— Kendrick, 1994: 130.— Kendrick & Walker, 1994: 201.
Carpacanthus distichus (Sonder) Kützing, 1849: 622.
Taxonomic synonym:
Sargassum aemulum Sonder, 1853: 672 (type locality: Holdfast Bay [Gulf St. Vincent], South Australia).—Grunow, 1915 [1915–1916]: 376.
INDIAN OCEAN DISTRIBUTION: Australia.
Note: The synonymy was proposed by Womersley (1987: 444, 446).