Aulacodiscus amoenus var. sparsipunctata. Single example on the slide mounted in Canada Balsam. Unknown maker. Olympus BHB microscope using 450nm LED light. 40x Leitz Pl Apo 1.00 objective, oil immersion. Olympus Aplanat Achromat condenser, oil immersion, oblique lighting. 2.5x Nikon CF PL photoeyepiece. Monochrome converted Nikon d850 camera. 66 images stacked in Zerene (Pmax).
Aulacodiscus amoenus var. sparsipunctata Desikachary & Sreelatha, 1989. Original description: Desikachary, T.V. & Sreelatha, P.M. (1989). Oamaru Diatoms. Bibliotheca Diatomologica, 19: pp. 3-330, pls 1-145. Pages 58-59, Plate 21, Figure 1-2.
I recently acquired about 30 more slides by this maker to add to the ones I already had, so if you want to see others by them, search for AAAAA in the Search option at the top of the page, and I’ll include this in each of the pages for them.