Eunotia nupeliana D.T.Ruwer & L.Rodrigues, sp. nov. (Figs 2–11)

Description: —Dorsiventral valves, narrowing towards the ends, rounded to subcapitate apices slightly dorsally deflected. Ventral margin slightly concave. Dorsal margins convex with three slight undulations in all cell cycle stages, less visible in smaller specimens (n=30). Valve length 21.0–56.6 μm, valve width 5.0–6.8 μm. Areolae not distinguishable under LM. Striae slightly radiate, denser at the apices, spaced, 11–14 in 10 μm in the middle of the valve. Striae composed of continuous rows of rounded areolae, 40–50 areolae in 10 μm. No spines were observed. Terminal raphe fissures positioned very close to the apical valve margin extending over almost the entire apical end.

Type locality: — BRAZIL. Mato Grosso do Sul: Taguaruçú, Patos Lake, Upper Paraná River Floodplain, sediment core, 22°45’31.98” S, 53°17’52.60” W, D. T. Ruwer, March 2018 (holotype, designated here, Nupélia UEM ! 18099 = Fig. 2) .

Etymology: —The species epithet refers to ‘ Nupélia – Núcleo de pesquisas em limnologia, ictiologia e aquicultura ’ a research center specialized on limnology, ichthyology and aquaculture at the State University of Maringá, focusing on biodiversity and aquatic ecology of the Upper Paraná River floodplain for the past 30 years.