长河螺，软体动物门-腹足纲-中腹足目-田螺科。维基百科Rivularia is a genus of cyanobacteria of the familia Rivulariaceae. [1]Description[edit]Rivularia is found growing on submerged stones, moist rocks and on damp soils near the riverside. The alga 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 aptical portion which is whip or tail like consisting of a row of small cells. Akinetes are absent in Rivularia. Rivularia multiplies with the aid of hormogonia and heterocyst.Species[edit]Rivularia atra Roth ex Bornet & Flahault, 1886Rivularia bullata (Poir) Berkeley ex Bornet & Flahault, 1886Rivularia haematites (De Candolle) Bornet & Flahault, 1886Rivularia jaoi H.-J.Chu, 1952Rivularia nitida C.Agardh ex Bornet & Flahault, 1886Rivularia thermalis Y.-Y.Li, 1984Species brought into synonymyRivularia cornudamae Roth, 1797: synonym of Chaetophora lobata Sc