FIGURES 28–33 in Two multi-stigmate Gomphonema species of Africa: Gomphonema kalahariense (nom. nov., stat. nov.) and Gomphonema chemeron (sp. nov.)

FIGURES 28–33. SEM images of Gomphonema chemeron. Figs. 28, 29. External views. Fig. 28. Girdle view at the apex with uniseriate rows of areolae comprising striae evident. Fig. 29. Valve view of central area with numerous (4) stigmata present. Figs 30-33. Internal views. Fig. 30. Entire valve view. Central nodule has 5 stigmata openings and recurved proximal raphe ends. Fig. 31. Central area to headpole, with central nodule bearing 3 stigmata openings and recurved proximal raphe ends. At the headpole, both a septum and pseudoseptum are present. Fig. 32. Footpole with prominent pseudoseptum evident, covering the helictoglossa. Fig. 33. Entire valve, with central nodule bearing 4 stigmata openings and proximal raphe ends barely visible. Striae can be seen extending onto the mantle. A remnant pseudoseptum is present at the headpole. Scale bars are indicated in the images.