An arrangement of three Stylobiblium sp. from Quesnel, Canada. Two facing upwards with the top towards the coverslip and one (the lower left one) with the top facing downwards. Some issues with the mountant/fixative as shown with the partially processed image. Prepared by JA long. 63x Leitz Pl Apo 1.4 objective, oil immersion. Olympus Aplanat Achromat condenser, oil immersion, brightfield lighting. 2.5x Nikon CF PL photoeyepiece. Monochrome converted Nikon d850 camera. 39 images stacked in Zerene (Pmax).
Based in Schmidt’s Atlas, I think this is probably Tetracyclus ellipticus (perhaps var. latissima), as shown in Schmidt’s Atlas, Plate 182, Figs 20-22. I did some measurements of the ‘dot’ spacing on the large one in the upper middle of the image using ImageJ, which came out at about 385nm (from the middle of one dot to the next).