Triceratium stokesianum var. moravica from Szurdok Puspoki (Szurdokpüspöki, a village in in Nógrád County, Hungary). Single example on the slide. Prepared by JA Long. Olympus BHB microscope using 450nm LED light. 63x Leitz Pl Apo NA 1.4 objective, oil immersion. Olympus Aplanat Achromat condenser, oil immersion, oblique lighting. 2.5x Nikon CF PL photoeyepiece. 11mm removed from the tube the camera to increase the field of view. Monochrome converted Nikon d850 camera. 56 images stacked in Zerene (Pmax). Touching the coverslip by the end, and I could have done with being able to go a bit deeper, but overall it has worked well.
Location known as a Miocene deposit. See: Hydrocarbon source rock potential of Miocene diatomaceous sequences in Szurdokpüspöki (Hungary) and Parisdorf/Limberg (Austria), E Tulan, MS Radl, RF Sachsenhofer, G Tari, J Witkowski, Austrian journal of earth sciences 2020, 113 (1), 24-42.
Triceratium stokesianum var. moravica Grunow in Schmidt et al., 1886. Original description: Schmidt, A. (1886). Atlas der Diatomaceen-kunde. Aschersleben, Commissions-Verlag Von Ludwig Siever’s Buchandlung. Series III (Heft 27-28): pls. 105-112. Plate 112 Figure 19, Plate 159 Figure 2 (as ‘Stockesianum’).
Parent: Triceratium stokesianum R.K.Greville, 1866 accepted as Entogoniopsis stokesiana (R.K.Greville) J.Witkowski, P.A.Sims, N.I.Strelnikova & D.M.Williams, 2015.