FIGURES 43–48 in Ultrastructure of four Surirella taxa (Bacillariophyceae) from Qinghai Province, northwest China, with reference to the characteristics of portulae

FIGURES 43–48. Surirella minuta, SEM, external view. 43, 44. Two valves showing the valve shape and the pattern of costa-stria bundles (CSB, labeled with white arrows in Fig. 43) alternated with over-fibula costae (OFC, labelled with black arrows in Fig. 43) from pole to pole. 45, 46. Details of the middle section of the valve (Fig. 45 from Fig. 43, Fig. 46 from Fig. 44), note the pattern of CSB alternated with OFC and multiseriate striae. 47, 48. Details of the apices from Fig. 43. Note the raphe endings interrupted at both the headpole (Fig. 47) and footpole (Fig. 48). Scale bars = 5 μm (Figs 43, 44), 1 μm (Figs 45–48).