Two examples of Actinoptychus amblyoceros from Conset, Barbados. Mounted in Sirax and dated April 1941. Some issues visible in the mountant. Prepared by Samuel Henry Meakin. Olympus BHB microscope using 450nm LED light. As well as the pair I imaged the right hand one using the 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. 62 images stacked in Zerene (Pmax).
Actinoptychus amblyoceros (Ehrenberg) A.W.F.Schmidt 1874. Published in: Schmidt, A.[W.F.] (1874). Atlas der Diatomaceenkunde. Series I, Heft 1. pp. pls 1-4. Aschersleben: [Verlag von Ernst Schlegel]. Plate 1, Figure 25. This name is currently regarded as a synonym of Symbolophora amblyoceros (Ehrenberg) G.R.Hasle & P.A.Sims. One of the other names it is known as is Schuettia amblyoceras (Ehrenberg) De Toni 1894. I’ve not seen one of the ‘convex’ sided ones before.