Stictodiscus minor D.M.Williams, P.A.Sims, & J.Witkowski, 2021

Williams, David M., Sims, Pat A. & Witkowski, Jakub, 2021, Notes on the diatom collection of the Natural History Museum, London (BM) V: (a) ‘ Stictodiscus manillensis’ nom. nud., (b) Stictodiscus pantocsekii and ‘ Stictodiscus pantocsekii var. minor’, (c) a note on the name ‘ Stictodiscella’; and (d) some comments on Jósef Pantocsek’s Beiträge zur Kenntnis der Fossilen Bacillarien, Phytotaxa 507 (2), pp. 167-174 : 171

Stictodiscus minor D.M.Williams, P.A.Sims, & J.Witkowski , sp. nov.

Synonym: Stictodiscus pantocsekii var. minor Tempère , nom. nud.

Type:— Barbadoes , ‘ Mt. Hillaby, nov.’[Mount Hillaby], Late Eocene, (holotype BM Adams GC 2839 = Fig. 12 , one specimen)

Valves triangular, each side gently convex, valve face flat; mantle distinctive. Valve with central annulus, radiating network of ‘siliceous bars’ leading to uniseriate areolae. Raised siliceous thickenings surround series of radiating inner areolae, becoming more conspicuous towards valve mantle. No other surface structures.

Figures

FIGURES 9–12. 9. Stictodiscus pantocsekii after Tempère (in Brun et al. 1890: pl. 4, fig. 6, see Fig. 9). 10. Drawing of Stictodiscus pantocsekii from Pantocsek (1892: pl. II, fig. 31). 11. Stictodiscus pantocsekii, BM 52932. 12. ‘Stictodiscus pantocsekii var. minor’, BM Adams GC 2839, holotype, ‘Mt. Hillaby, nov.’, Chimborazo, Barbadoes. Scale bars = 20 μm.