An arrangement of five Aulacodiscus archangelskianus from Singiliewsky, Russia. Prepared by JA Long. Olympus BHB microscope using 450nm LED light. 20x Nikon Plan Apo NA 0.65 objective. Olympus Aplanat Achromat condenser, oblique lighting. 2.5x Nikon CF PL photoeyepiece. Monochrome converted Nikon d850 camera. 42 images stacked in Zerene (Pmax).
Aulacodiscus archangelskianus Witt 1886. Published in: Witt, O.N. (1886 ‘1885’). Ueber den Polierschiefer von Archangelsk-Kurojedowo im Gouv. Simbirsk. Verhandlungen der Russisch-kaiserlichen Mineralogischen Gesellschaft zu St. Petersburg, Series II 22: 137-177, pls. VI-XII. Page 154, Plate 6, Figures 11,12.