Blossevillea expansa Areschoug, 1854b: 337–338, nom. illeg. (type locality: Port Phillip, Victoria, Australia).
Cystophora expansa Womersley, 1964: 77–78, figs. 15–17, pl. 5: fig. 2.—Womersley, 1987: 382, 384.
INDIAN OCEAN DISTRIBUTION: Australia.
Note: Blossevillea expansa Areschoug, the intended basionym of Cystophora expansa, is not priorable since it is a later homonym of B. expansa (C. Agardh) Trevisan (1845: 64), which is based on Cystoseira expansa C. Agardh (1825: 8; type locality: "In mari australi'' [probably Monterey, California, U.S.A.]). The latter was treated as Cystoseira osmundacea (Turner) C. Agardh forma expansa (C. Agardh) Setchell by Setchell (in Collins, Holden, & Setchell, 1901 [1895–1919]: no. XLVIII). Cystophora expansa Womersley is treated as a nomen novum in accordance with Art. 58.3.