Planothidium comperei sp. nov. (Bacillariophyta), a new diatom species from Ivory Coast

Background and aims - The diatom flora from West African rivers remains virtually unknown. In this context, and given the restricted literature for the region, we explored the diatom communities from the Agnéby and Mé river watersheds, Ivory Coast. Methods - Diatoms were sampled on glass slides previously immersed during a period of thirty days, at different sites along the Agnéby and the Mé River. Species were identified using light and scanning electron microscopy. Key results - Among the 258 taxa recorded, Planothidium comperei sp. nov. is the most abundant. A thorough description of this species is proposed. This new species shows morphological similarities with Planothidium miotum (J.R.Carter & Denny) Lange-Bert., whose type material from Sierra Leone is illustrated in light microcopy for comparison. A second species originally described as Achnanthes piafica J.R.Carter & Denny is also illustrated and combined in the genus Planothidium.