FIGURES 20–25. SEM, internal valve views. Fig. 20 in Halamphora daochengensis sp. nov., a new freshwater diatom species (Bacillariophyceae) from a small mountain lake, Sichuan Province, China

FIGURES 20–25. SEM, internal valve views. Fig. 20. Internal view of entire valve with girdle bands. Fig. 21. Oblique view of valve. Fig. 22, 23. Internal view of valve apex with prominent helictoglossa. Fig. 24. Internal view of valve centre with girdle bands. Fig. 25. Internal view of valve centre with fused helictoglossa. Scale bars = 2 μm (Figs 22, 23), 3 μm (Fig. 25), 5 μm (Figs 20, 21, 24).