FIGURES 59–64 in Surirella arctica comb. et stat. nov. (Bacillariophyta)-a rare arctic diatom

FIGURES 59–64. Surirella arctica, girdle views. SEM. The pairs of Figs 59–60, 61–62 and 63–64 each represent one of the observed specimens—a complete frustule on the left and a close-up detail on the right; Figs 59–60 show the same specimen as in 43–46, although rotated and tilted. Figs 59, 63 Whole frustules. Fig. 60 Detail of the cingulum showing an open girdle band, and a ligula. Fig. 61 Frustule with an open girdle band. Fig. 62 Valve apex showing the raphe on a keel. Fig. 64 Frustule apex in girdle view showing mantle partially covered by a thin siliceous lamella along the valve edge, the raphe slits and the ornamented girdle bands. Scale bars = 10 µm (in Figs 59, 61, 63) or 1 µm (in Figs 60, 62, 64).