A strew from Flawes Creek, Oamaru, New Zealand. A range of diatoms present. Prepared by Klaus Kemp. Mounted in Styraclor and dated March 1995. I’ve picked examples of what I think are Hyalodiscus sp. for further imaging. 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. Image stacks prepared in Zerene (Pmax).
1. Hyalodiscus sp.? Not sure about this one but it has features similar to Hyalodiscus sp. hence the question mark. It is dome shaped. 74 images stacked.
2. Fragment of Hyalodiscus sp.. This is quite a large fragment of what looks to be the middle of a Hyalodiscus sp. Perhaps Hyalodiscus radiatus or Hyalodiscus radiatus var. arctica. 46 images stacked.
3. Hyalodiscus sp.. 53 images Pmax
4. Hyalodiscus franklinii ?. Viewed from the underside. Maybe Hyalodiscus franklinii but I am not sure about that. 41 images stacked.