A strew from Creswell, England, with examples of Attheya decora. A lot of mold present. The Attheya are really difficult to see as they are low contrast compared with the surroundings, but there are a lot on the slide. No makers name. Olympus BHB microscope using 450nm LED light. As well as the wider arrangement I imaged one of the A. decora with 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. 8 images stacked in Zerene (Pmax) – very thin diatom. There was a hotspot in the middle of the frame which I’ve not seen before. Seems to be particular to this slide. I cleaned up some of the dirt in the processing of the image.
Attheya decora T.West 1860. Published in: West, T. (1860). Remarks on some Diatomaceae new or imperfectly described and a new desmid. Transactions of the Royal Microscopical Society, series 2 8: 147-153. Page 152, Plate 7, Figure 15. Also see: Crawford, R. M., Gardner, C., & Medlin, L. K. (1994). The genus Attheya. I. A description of four new taxa, and the transfer of Gonioceros septentrionalis and G. armatas. Diatom Research, 9(1), 27-51. https://doi.org/10.1080/0269249X.1994.9705286
Interesting one this. Every now and then I come across a new name, and this was new for me. Initially took me a while to find them as they are so pale and thin.