Glyphodiscus stellatus from Oamaru, New Zealand. Single example on the slide. No makers name, but based on style this was prepared by Richard Gosden. Olympus BHB microscope using 450nm LED light. 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. 20 images stacked in Zerene (Pmax). I got a bit lucky with this, and just managed to get deep enough for imaging with the 63x Leitz objective. Quite a low contrast slide, which coupled with the small size made it a bit of a challenge to image.
Described in: Greville, R.K. (1862). Descriptions of new and rare diatoms. Series VI. Transactions of the Microscopical Society, New Series, London 10: 89-96, pl. IX.