An arrangement of two Aulacodiscus quadrans from Ananino, Russia. This is apparently a Cretaceous site. Prepared by WA Firth. Olympus BHB microscope using 450nm LED light. The larger one was imaged using a 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. 59 images stacked in Zerene (Pmax). 22 images stacked for the image of the arrangement.
Aulacodiscus quadrans. Aulacodiscus quadrans A.W.F.Schmidt 1876. Published in: Schmidt, A.[W.F.] (1876). Atlas der Diatomaceen-kunde. Series I: Heft 9. pp. pls. 33-36. Aschersleben: Verlag von Ernst Schlegel. Plate 35, Figure 10; nomen.