An arrangement of 6 diatoms supposedly from Hayti [Haiti]. The label says Actinocyclus, Coscinodiscus, Porodiscus and something else which I can’t read. The arrangement is linear, but I have split them into two parts so the final image isn’t just a long letterbox. The images were surprisingly low contrast, and I am not 100% sure why. The objective was ok, but I have seen some of the slides by this maker are a bit foggy. Olympus BHB microscope using 450nm LED light. 20x Nikon Plan Apo NA 0.65 objective. Olympus Aplanat Achromat condenser, oblique lighting. 2.5x Nikon CF PL photoeyepiece. Monochrome converted Nikon d850 camera. Two stacks prepared in Zerene (Pmax). Top row of 4, 32 images. Bottom row, 38 images. Here’s my thoughts on the diatoms.
1. Actinocyclus sp.
2. Coscinodiscus sp.
3. Cestodiscus sp.
4. Coscinodiscus sp.?
5. Porodiscus interruptus? This is from Truan y Luard, A. & Witt, O.N. (1888). Die Diatomaceen der Polycystinenkreide von Jérémie in Hayti Westindien. pp. [1]–38, incl. 7 pls [I-VII]. Berlin: Verlag von R. Friedländer & Sohn (Plate III, Fig 22). However it looks more like a Hyalodiscus sp. to me.
6. Rattrayella sp. Highly tilted. R. simbirskiana (looks like it but not expected in Haiti)?
I recently acquired about 60 slides by this maker, so if you want to see others by them, search for AAAAA in the Search option at the top of the page, and I’ll include this in each of the pages for them.