Slide labelled as Stauroneis baileyii from Cornwall Island, Nova Scotia (I think this is likely Price Edward Island, given it’s location and that it has a place called Cornwall on it. No makers name. Olympus BHB microscope using 450nm LED light. As well as the main body of diatoms I imaged two of them with a 50x Leitz Fluoreszenz NA 1.00 objective, water immersion. Olympus Aplanat Achromat condenser, water immersion, oblique lighting. 2.5x Nikon CF PL photoeyepiece. Monochrome converted Nikon d850 camera. Images stacked in Zerene (Pmax). I couldn’t get close enough with either the 40x or 63x Leitz Pl Apo objectives, hence the use of the 50x with its long working distance. Most of the diatoms look similar (presumably the S. baileyi), however one stood out as different, and I have also imaged that one. Not sure as to species – any ideas, let me know. The image labelled as S. baileyi is an underside view, with the rim towards the coverslip, the other one is the topside upwards (rim down, away from the coverslip). The one I am not sure of the name for was smaller than the others, and can be seen in the 10x objective image just up and right of the middle of the photo.
Stauroneis baileyi Ehrenberg 1843. Published in: Ehrenberg, C.G. (1843). Verbreitung und Einfluss des mikroskopischen Lebens in Süd- und Nord-Amerika. Abhandlungen der Königlichen Akademie der Wissenschaften zu Berlin 1841: [291]–445 + [1, Berichtigungen], pls 1–4. Page 422. Homotypic synonym: Stauroneis phoenicenteron var. baileyi (Ehrenberg) Cleve 1894. Published in: Cleve, P.T. (1894). Synopsis of the naviculoid diatoms. Part I. Kongliga Svenska Vetenskapsakademiens Handlingar Series 4 26(2): 1-194, 5 pls. Page 149. Also see Schmidt’s Atlas Plate 242, Figure 13.