Auliscus racemosus from Oamaru, New Zealand. Single example on the slide. Described as ‘scarce’. Not really visible in the image above, but the glass of the slide has a slight blue tinge to it. Although there is no name on the slide this was prepared by Frederick Marshall. Olympus BHB microscope using 450nm LED light. 63x Leitz Pl Apo NA 1.40 objective, oil immersion. Olympus Aplanat Achromat condenser, oil immersion, brightfield lighting. 2.5x Nikon CF PL photoeyepiece. Monochrome converted Nikon d850 camera. 36 images stacked in Zerene (Pmax).
This is an unusual and I think quite pretty diatom, and I have a few examples of it (for others use the Search function).