Figs 33–38. Mastogloia belaensis M in Morphology of two Mastogloia species (Bacillariophyta) from Lac de Guiers (Senegal) and comparison with the type material of M. braunii

Figs 33–38. Mastogloia belaensis M.Voigt. Scanning electron micrographs (SEM) of valves from the Lac de Guiers population (Van de Vijver sample SEN-42). 33. SEM girdle view of an entire frustule showing the partectal pores and the mantle areolae. 34. SEM external view of an entire valve with typical undulating raphe branches. 35. SEM external detail of the central area. 36. SEM external detail of the valve apex. 37. SEM external detail of the apices and girdle bands of an entire frustule. 38. SEM external detail of the valve mantle with the transapically elongated mantle areolae and the row of rounded pseudoloculi on the valve face/mantle junction. Scale bars: 10 µm.