An arrangement of three Asteromphalus ralfsianus. All with some damage, but mostly intact. Prepared by Watson and Sons Ltd. Olympus BHB microscope using 450nm LED light. I selected one for imaging at higher resolution using a 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. 69 images stacked in Zerene (Pmax).
Asteromphalus ralfsianus (G.Norman) Grunow 1867. Published in: Grunow, A. (1867). Diatomeen auf Sargassum von Honduras, gesammelt von Linding. Hedwigia 6(1-3): 1-8, 17-32, 33-37. Page 32.