Fig. 2 in Tertiarius minutulus sp. nov. (Stephanodiscaceae, Bacillariophyta) - a new fossil diatom species from Lake Ohrid

Fig. 2. Tertiarius minutulus sp. nov., SEM external valve views. A. Valve view showing the marginal openings of the fultoportulae (see white arrow). B–D. View of the whole frustule. E. Close view of marginal openings of the fultoportula (see white arrow). F. Close view of the external openings of the valve face fultoportulae (see white arrows). Scale bars: A–D = 2.0 µm; E–F = 1.0 µm.