Hemidiscus bicurvans from Conset, Barbados. Single example on the slide. Mounted in Styrax. Some issues with the mountant. Prepared by RI Firth. Olympus BHB microscope using 450nm LED light. 40x Leitz Pl Apo 1.00 objective, oil immersion. Olympus Aplanat Achromat condenser, oil immersion, oblique lighting. 2.5x Nikon CF PL photoeyepiece. Monochrome converted Nikon d850 camera. 61 images stacked in Zerene (Pmax). Quite a small diatom, and I couldn’t get close enough to use the 63x Leitz, which has limited the size and resolution of the image.
Hemidiscus bicurvans Barker & Meakin, 1949. Published in: Barker, J.W. & Meakin, S.H. (1949). New and rare diatoms. Journal of the Quekett Microscopical Club, Series 4 2(6): 301-303, pls 37,38. Page 302, Plate 38, Figure 7. Described as ‘Conset, Barbados, rare.’. Screen shots of the figure and text are shown above.