Mesothamnion caribaeum Børgesen, 1917: 208–216, figs. 194–200 (type locality: off Annaberg, St. John, Virgin Islands).—Jaasund, 1976: 113, figs. 228A,B.— Jaasund, 1977b: 407.— Lawson, 1980: 57.— Wollaston, 1984: 293.— B. Subramanian, 1985a: 72, 80, figs. 11–15.
Pleonosporium caribaeum (Børgesen) R. Norris, 1985: 61.—Stegenga, 1986: 92–94, pl. 31.— Bolton & Stegenga, 1987: 177.— R. Anderson & Stegenga, 1989: 303.— Bolton & Stegenga, 1990: 237.— Stegenga & Bolton, 1992: fig. 3, table I.
INDIAN OCEAN DISTRIBUTION: Australia, India, Mozambique, South Africa, Tanzania.
Note: R. Norris (l.c.) merged the genus Mesothamnion Børgesen (1917: 208) with Pleonosporium (Nägeli) Nägeli ex Hauck (1882 [1882–1885]: 87), nom. cons.