FIGURES 22–28 in Haslea crucigeroides var. australis, var. nov. (Bacillariophyta), a new marine diatom from southern South America and Antarctica

FIGURES 22–28. SEM images of Haslea crucigeroides var. australis, var. nov. 22. Part of a frustule in girdle view. Note the external tegumental layer with continuous longitudinal fissures, except on the valve margin (white arrows). The cingulum presents the valvocopula and a copula (black arrows). 23. Valve in external view showing continuous longitudinal fissures, raphe sternum and small central area with the raphe fissures. 24, 25. Apices of the same valve showing the terminal raphe fissures strongly deflected to the same side. 26. Entire valve in internal view. 27. Details of the transverse and longitudinal striae in internal view. Note the rectangular areolar foramina at the valve margin. 28. Detail of the foramina occluded internally by hymenes. Scale bar = 10 μm (Figs 22, 26), 2 μm (Figs 23–25, 27, 28).