Rivularia (cyanobacteria)
Rivularia is a genus of cyanobacteria of the family Rivulariaceae. Description. "Rivularia" is found growing on submerged stones, moist rocks, and damp soils near the riverside. It is found in colonies, and the trichomes are radially arranged within a colony, with each trichome wholly or partially surrounded by a gelatinous sheet. The trichomes have a basal heterocyst. Each trichome has a narrow aptic portion which is whip- or tail-like consisting of a row of small cells. Akinetes are absent in "Rivularia". The species multiply with the aid of hormogonia and heterocyst.