Slide labelled as Asterolampra decora (more in a minute on this) from Chalky Mt, Barbados. Single example on the slide. 0.004” thick coverslip (0.10mm). Prepared by William Allott Firth. Olympus BHB microscope using 450nm LED light. 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. 35 images stacked in Zerene (Pmax).
Asterolampra decora Greville, 1862. Published in: Greville, R.K. (1862). On the Asterolamprae of the Barbadoes deposit. Transactions of the Microscopical Society, New Series, London 10(2): 41-55, pls VII, VIII. Page 45, Plate VII [7], Figures 4-6.
However is this right? It is not particularly similar to another a slide labelled as A. decora here – https://diatomimaging.com/asterolampra-decora-frederick-marshall/
However looking at Greville 1862, it does seem to be the best bet. But it also looks a bit like what I put down as A. affinis here – https://diatomimaging.com/asterolampra-sp-from-bissex-hill-jt-norman/ But that was with a question mark anyway.
Barbados has a huge range and variety of Asterolampra species, and as such for now I will leave it as A. decora but with a question mark.