Calothrix brebissonii Kützing, 1847a: 180 (type locality: Falaise, Calvados, France).—Dickie, 1874b: 200.
INDIAN OCEAN DISTRIBUTION: Mauritius.
Note: Gomont (1892b: 99) assigned this species to Plectonema tomasinianum (Kützing) Bornet, while Drouet (1968: 144, 154), after examining the holotype (in L), assigned it to Porphyrosiphon notarisii (Meneghini) Kützing.