Microchaete grisea Thuret in Bornet & Thuret, 1880: 127, 128, pl. XXX: figs. 1–4 (type locality: Le Croisic, Loire-Atlantique, France).—Jadin, 1894: CLXX.— Forti, 1907: 485.— Geitler, 1931 [1930–1932]: 666–667, fig. 427.— Frémy, 1939: 56.— Newton, 1955b: 144.— S. Dixit, 1980: 60.— Untawale, Dhargalkar, & Agadi, 1983: [41].— G. Subramanian et al., 1989: 314, 317.— Thajuddin & G. Subramanian, 1992a: table III.
INDIAN OCEAN DISTRIBUTION: Bahrain, India, Mauritius.
Note: Drouet (1973: 175, 186), after examining the holotype of this species (in PC), assigned it to Calothrix crustacea Thuret.