Dicladia capreolus from South Africa. 3 examples on the slide, one viewed from the top looking down on the ‘spikes’ and two viewed from the side. Mounted in Hyrax. No makers name. Olympus BHB microscope using 450nm LED light. 40x Leitz Pl Apo NA 1.00 objective, oil immersion. Olympus Aplanat Achromat condenser, oil immersion, slightly oblique lighting. 2.5x Nikon CF PL photoeyepiece. Monochrome converted Nikon d850 camera. 59 images stacked in Zerene (Pmax). I’ve shown the image in two ways. The original arrangement, and then with the three forms closer together with a lot of the space removed.
Ok, what is Dicladia capreolus? As far as I can tell this is a spore form of Chaetoceros. In particular there is this regarding them “fossil resting spores….. It is assumed they are associated with the genus Chaetoceros” from Itsuki Suto, Taxonomy of the marine diatom resting spore genera Dicladia Ehrenberg, Monocladia Gen. Nov. and Syndendrium Ehrenberg and their stratigraphic significance in Miocene strata, Diatom Research, 2004, 18:2, 331-356, DOI: 10.1080/0269249X.2003.9705596