Morphology of new taxa in the **Cymbella aspera** and **Cymbella neocistula** groups, **Cymbella yakii** sp. nov., and **Cymbella** cf. **hantzschiana** from Everest National Park, NepalMorphology of new taxa in the **Cymbella aspera** and **Cymbella neocistula** groups, **Cymbella yakii** sp. nov., and **Cymbella** cf. **hantzschiana** from Everest National Park, Nepal
Faculty of Sciences. Biology
Polish botanical journal. - Krakow
55(2010):1, p. 73-92
University of Antwerp
Three new species and one new variety of the genus Cymbella are described from the Gokyo and Dudh Koshi Valleys in Everest National Park, Nepal. Cymbella himalaspera Juttner & Van de Vijver and C. subhimalaspera Juttner & Van de Vijver are related to species in the group around C. aspera (Ehrenberg) H. Peragallo but differ from similar taxa with respect to the shape of the areolae, the proximal raphe endings and the stigmata. Cymbella neocistula var. nepalensis Juttner & Van de Vijver differs from the nominate form in valve shape. Cymbella yakii is similar to species around C. parva (W. Smith) Kirchner in Cohn and C. excisa Kutzing but differs in valve shape and the number of stigmata. A taxon similar to C. hantzschiana Krammer is described in detail.