FIGURES 2–22. Planothidium galaicum. Type population. Figs. 2–19 in Planothidium galaicum sp. nov. (Bacillariophyta, Achnanthidiaceae), a new diatom species from Galician coast, Spain

FIGURES 2–22. Planothidium galaicum. Type population. Figs. 2–19. LM micrographs. Figs. 20–22. SEM micrographs. Figs. 2–6. Rapheless valves. Figs. 7, 13, 19. Girdle views of an entire frustule. Figs. 8–12, 14–18. Raphe valves. Fig. 20. Internal view of rapheless valve showing the raised sternum and the interstriae. Fig. 21. External view of a rapheless valve showing the spinules developed in the interstriae. Fig. 22. External detail of the apex of the rapheless valve showing the spinules, which are wider in the valve margin. Scale bar: 10 µm (Figs. 2–19), 2 µm (Figs. 20, 21), 1 µm (Fig. 22).