Ulnaria ulna (Nitzsch) Compère (2001: 100) Figs 3: AX–AZ Length: 78.7–212.4 µm; width: 6–8.4 µm; striae: 8–11 in 10 µm (n = 18) Teratological form: deformed valve outline, undulated or with strong constriction in the median portion of the valve. Slight alteration in the striae pattern. Occurrence: S1, S2, S3, S6, S8. Ecological characteristics: Cond.: 38.00–78.00 µS cm –1; BOD: 0.1–9.9 mg L− 1; COD: 1.22–24.32mg L− 1; N-NH: 8–316 µg L− 1; NO: 3 3 − 1 − 1 − − 1 − 1 0.34–17.20 mg L; DO: 5.84–22.80 mg L; pH: 5.31–7.09; PO: 0.005 –0.030 mg L; TP: 0.005–0.82 mg L; TS: 10.00–72.00 4 mg L− 1; Temp.: 17.37–23.24 °C; Turb.: 1.93–10.7; Flow: 0.027–4.17 m 3 s; Average depth: 0.02–0.29 m; Prec.: 2.36–9.98 mm. Metal concentrations: Co: 18.10–55.52 mg L –1; Cr: 24.51–85.01 mg L –1; Cu: 170.45–245.83 mg L- 1; Mn: 345.77–639.87 mg L –1; Ni: 32.41–78.27 mg L –1; Pb: 24.07–52.76 mg L –1; Zn: 123.32–412.52 mg L –1.

Published as part of Amaral, Mailor Wellinton Wedig, Medeiros, Gabriela, Daufenbach, Vanessa, Sampaio, Silvio Cesar, Reis, Ralpho Rinaldo Dos, Ludwig, Thelma Alvim Veiga & Bueno, Norma Catarina, 2024, Taxonomy of epilithic diatoms and teratological forms under the presence of metals in surface sediment, pp. 237-273 in Phytotaxa 647 (3) on page 243, DOI: 10.11646/phytotaxa.647.3.3, http://zenodo.org/record/13215724