Cavinula lilandae (Bacillariophyta), a new diatom species from the Congo Basin, Central Africa

Abstract

Cavinula lilandae, a small new diatom from the Congo Basin in Central Africa, was observed in acid riverine habitats in an almost pristine tropical rain forest. It occurred in a periphytic diatom community dominated by Eunotia spp. and Fragilariforma strangulata (Zanon) Williams & Round. Beside the type locality in the Baomba Stream, and the closely located Lilanda River, in the Democratic Republic of Congo, this taxon was also observed in a small river in Zambia, north of the Bangweulu swamps. Cavinula lilandae is distinguished from other taxa within the genus Cavinula D.G. Mann & A.J. Stickle by the following characteristics: uniseriate striae becoming irregularly biseriate near the poles; irregularly formed areolae; and irregular depressions in the valve face close to the axial area which are not perforating the valve face.