Cryptogamie, Algologie
28 (3) - Pages 283-287During the 2005 phytoplankton survey of the Lake of Geneva, the authors found a new colonial form of the diatom Fragilaria tenera (W. Smith) Lange-Bertalot. It is herein named Fragilaria tenera var. lemanensis. This new colonial form differs from the other taxa of Fragilaria by its particularly "asteriform" colonies, long and fine valves, little visible striae and capitate to hardly capitate extremities.