Pseudauliscus ralfsianus from Conset, Barbados. Single example on the slide. Prepared by JA Long. Olympus BHB microscope using 450nm LED light. 40x Leitz Pl Apo 1.00 objective, oil immersion. Olympus Aplanat Achromat condenser, oil immersion, oblique lighting. 2.5x Nikon CF PL photoeyepiece. Monochrome converted Nikon d850 camera. 72 images stacked in Zerene (Pmax). There was a sponge spicule but that had moved into the red ring. Couldn’t get close enough to use the 63x Leitz.
Pseudauliscus ralfsianus (Greville) Rattray 1888. Published in: Rattray, J. (1888). A revision of the genus Auliscus Ehrenberg and of some allied genera. Journal of the Royal Microscopical Society 1888: 861-920, 5 pls [XII-XVI]. Page 903.
Auliscus ralfsianus Greville 1863. Published in: Greville, R.K. (1863). A monograph of the genus Auliscus. Transactions of the Microscopical Society, New Series, London 11: 36-53, pls II, III. Page 52, Plate III, Figure 21.
Looks like this was originally Pseudoauliscus then became Auliscus later.
Also reported as Cerataulus pacificus, Eupodiscus barbadensis, Auliscus cellulatus (discussed in Rattray, 1888).