Aulacodiscus sp. from Oamaru, New Zealand. Three examples of Aulacodiscus amoenus (written as ‘amoebus‘ on the label), one of Aulacodiscus angulatus, and the fragments of a larger species. Broken coverslip. Mounted in Styrax and dated 1948. Prepared by CL Odam. Olympus BHB microscope using 450nm LED light. I imaged the A. angulatus 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. 94 images stacked in Zerene (Pmax).
Aulacodiscus angulatus Greville 1863. Published in: Greville, R.K. (1863). Descriptions of new and rare Diatoms. Series IX. Transactions of the Microscopical Society, New Series, London 11: 63-76, pls IV,V. Page 71, Plate 5, Figure 15.