Navicula sp. from Tamatave (Toamasina, Madagascar). Single example on the slide. Prepared by William Allott Firth. Olympus BHB microscope using 450nm LED light. 63x Leitz Pl Apo 1.4 objective, oil immersion. Olympus Aplanat Achromat condenser, oil immersion, oblique lighting. 2.5x Nikon CF PL photoeyepiece. Monochrome converted Nikon d850 camera. 32 images stacked in Zerene (Pmax).
Currently not sure as to a species. Looks a little like Navicula clavata var. indica (Schmidt’s Atlas Plate 204, Figure 12), but the apices don’t look right. Any ideas, please let me know.