Aulacodiscus grunowii from St Peter, Hungary. Single example on the slide. No makers name, but made by Frederick Marshall. Olympus BHB microscope using 450nm LED light. 63x Leitz Pl Apo 1.4 objective, oil immersion. Olympus Aplanat Achromat condenser, oil immersion, slightly oblique lighting. 2.5x Nikon CF PL photoeyepiece. Monochrome converted Nikon d850 camera. 53 images stacked in Zerene (Pmax).