A strew slide from Flume Valley, Oamaru, New Zealand. Range of species present including a few Brightwellia fragments. Fossil marine material. No makers name but I think this is by ECP Bone. Olympus BHB microscope using 450nm LED light. I selected two of them for imaging at higher resolution. 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. Image stacks prepared in Zerene (Pmax).
Coscinodiscus superbus ? 23 images stacked. Underside view. Fairly sure of the ID, but will leave it with a question mark for now. Coscinodiscus superbus Hardman 1890. Published in: Rattray, J. (1890). A revision of the genus Coscinodiscus Ehrb., and some allied genera. Proceedings of the Royal Society of Edinburgh 16: 449-692, pls I-III. Page 458. I did wonder if this was Actinocyclus ingens, but I can’t see a typical Actinocyclus hole near the rim.
Stictodiscus californicus var. nitida. 23 images stacked. Fragment. Underside view. Stictodiscus californicus var. nitida Grove & Sturt 1887. Published in: Grove, E. & Sturt, G. (1887). On a fossil marine Diatomaceous deposit from Oamaru, Otago, New Zealand. Part III. Journal of the Quekett Microscopical Club, Series 2 3: 63-78, pls 5, 6. Page 66, Plate 5, Figure 7.