FIGURES 20–37 in New species of Stenopterobia (Bacillariophyta) from Colombia and Peru, and new nomenclatural transfers in Iconella

FIGURES 20–37. Stenopterobia colombiana sp. nov. LM (Figs 20–32) and SEM (Figs 33–37) images from type material LPC 5610-2. 20–32. Specimens in valve view showing size variation. 33. Valve in external view. 34. Detail of a valve in external view showing axial area with median rib (arrow), transapical costae, biseriate striae and fenestrae. 35. Detail of valve in internal view showing portulae, striae and the wide axial area in. 36. Detail of the internal valve view near the apex showing the portulae. 37. Detail of valve apex in internal view showing terminal raphe fissures. Scale bars: 1 µm (Figs 34–37), 10 µm (Figs 20–32), 20 µm (Fig. 33).