Fragilaria nevadensis sp nov., a new diatom taxon from a high mountain lake in the Sierra Nevada (Granada, Spain)

A new diatom taxon, Fragilaria nevadensis Linares-Cuesta & Sanchez-Castillo, was described based on light- and electron-microscope examination. It was isolated from a high-mountain lake in the Sierra Nevada (Granada, Spain), the highest mountain range in the Iberian Peninsula. The new taxon was characterised by its valve morphology and number of striae. Morphometric analysis suggested a relationships between F. nevadensis and the F. capucina complex, which is well represented in the Sierra Nevada by the variety rumpens. The comparison of F. nevadensis morphometric data of with those of other similar species showed that they are closely related to F. capucina var. austriaca. The ecological conditions of F. nevadensis and F. capucina var. austriaca are similar, both species growing in cold mountain waters (while F. heidenii and other similar species live in different kinds of water with a wider salinity spectrum).