Shionodiscus oestrupii (Ostenfeld) A. J. Alverson, S. - H. Kang & E. C. TheriotCoscinosira oestrupii Ostenfeld (1900): 52 — Fryxell and Hasle (1980); Hasle and Syvertsen (1997): 81, 82, pl. 13.Shionodiscus oestrupii — Alverson et al. (2006): 258; Wilks and Armand (2017); Guiry and Guiry (2025).DescriptionDiameter 21.7–23.9 (7–60) μm, pervalvar axis half to twice the diameter. Valve face flat or slightly convex. Mantle low and rounded. Areolae usually larger in central part of valve than closer to the margin, sometimes in sublinear array. One nearly central strutted fultoportula. Rimoportulae is 3–4 areolae from central process. Areolae 9 (6–12) in 10 μm at valve centre. MFPs 3–4 in 10 µm, 0.96–1.1 (0.8–1.9) µm between MFPs.NotesiNaturalist ID: 142951511, 142950297 (Fig. 35).