FIGURES 29–32 in Haslea crucigeroides var. australis, var. nov. (Bacillariophyta), a new marine diatom from southern South America and Antarctica

FIGURES 29–32. SEM images of Haslea crucigeroides var. australis, var. nov. 29. Internal view of a valve centre showing the pseudostauros, the short ridge on a side of the central nodule and the long ridge on the other side. 30. Detail of valve apex in internal view. Note the long ridge covering the raphe until reaching the helictoglossa. 31. Broken valve revealing its two-layer sandwich-type structure; note also its domed shape. 32. Detail of the tegumental and basal layers of the valve (upper and lower side, respectively) joined to each other by saepes (arrow). Basal layer seen on the left of the picture (arrow). Scale bar = 2 μm (Figs 29–31), 0.5 μm (Fig. 32).