FIGURES 26–33 in Gomphosphenia vallei (Bacillariophyta), a new diatom species from a stream in the "Réserve Naturelle Nationale de la Vallée de Chaudefour", Massif Central (France)

FIGURES 26–33. SEM images of Gomphosphenia vallei. Type populationfrom Pérouse Stream.26–30:External view of entire valve showing the raphe structure and the striae.31: Internalview of an entire valve showing the raphe structure and the striae:32–33:Girdle view of the frustule. Scale bar = 5 μm (Figs 29–31), 4 µm (Figs 27, 32), 3 µm (Figs 26, 33) and 2 µm (Fig. 28).