Note: This family was established by Anagnostidis & Komárek (1988: 374–380) as a segregate of the Oscillatoriaceae, from which it differs in several features, the most obvious of which is the shape of the cells (usually longer than broad except immediately after division). It comprises three subfamilies: Pseudanabaenoideae, including Pseudanabaena and Geitlerinema; Limnotrichoideae, including Limnothrix; and Leptolyngbyoideae, including Leibleinia, Leptolyngbya (= Spirocoleus in this catalogue), and Planktolyngbya.
Note: Anagnostidis (1989: 35) established this genus by elevating Phormidium subgen. Geitlerinema Anagnostidis & Komárek (1988: 404) to generic rank. He moved it from the Phormidiaceae to the Pseudanabaenaceae, tentatively assigning it to the subfamily Pseudanabaenoideae.
Oscillatoria amphibia C. Agardh, 1827: 632–633 (type locality: Carlsbad [Karlovy Vary], Czech Republic).—Biswas, 1926: 19–20, pl. VI: fig. 9.— Biswas, 1943: 112.— Desikachary, 1959: 229–230, pl. 37: fig. 6.— Allender, 1981: 22.— Thajuddin & G. Subramanian, 1992a: table III.
Geitlerinema amphibium (C. Agardh) Anagnostidis, 1989: 38.
INDIAN OCEAN DISTRIBUTION: Australia, India.
Note: Drouet (1968: 28, 69), after examining the holotype of this species (in LD), assigned it to Schizothrix calcicola (C. Agardh) Gomont.