Fragilaria tenera var. nanana (Lange-Bertalot) Lange-Bertalot & S.Ulrich (2014: 7)

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, Phytotaxa 647 (3), pp. 237-273 : 243

* Fragilaria tenera var. nanana (Lange-Bertalot) Lange-Bertalot & S.Ulrich (2014: 7)

Figs 3 : AL–AO

Length: 45.1–67.1 µm; width: 1.9–3.1 µm; striae: 20–22 in 10 µm (n = 30)

Taxonomical remarks: the individuals from Cascavel river micro-watershed contain a higher striae number (18.5–20 in 10 µm) than the original description. However, the authors pointed out that their specimens had lower striae density compared to the protologue provided by Meister ( Lange-Bertalot & Ulrich 2014).

Teratological form: deformed valve outline, undulated.

Figs 3 : AN–AO

Length: 45.1–54 µm; width: 2.1–2.5 µm; striae: 21–22 in 10 µm (n = 3)

Occurrence: S3.

Ecological characteristics: Cond.: 38.00–40.00 µS cm –1; BOD: 1.49–3.27 mg L− 1; COD: 7.23–8.08 mg L− 1; N-NH: 316–378 µg L− 1; 3 −1 −1 − −1 −1 NO: 0.37 mg L; DO: 11.42–14.57 mg L; pH: 5.79–6.19; PO: 0.006 –0.008 mg L; TP: 0.010 –0.017 mg L; TS: 38.00–66.00 3 4 mg L− 1; Temp.: 17.37–17.50 °C; Turb.: 7.03–10.70; Flow: 0.47 m 3 s; Average depth: 0.19–0.23 m; Prec.: 9.96 mm.

Metal concentrations: Co: 23.91–33.57 mg L –1; Cr: 27.33–78.86 mg L –1; Cu: 197.55–235.49 mg L –1; Mn: 398.50–444.52 mg L –1; Ni: 31.80–69.89; Pb: 35.58–46.56 mg L –1; Zn: 93.81–167.31 mg L –1.

Figures

FIGURE 3. Epilithic diatoms from Cascavel River micro-watershed in LM. A. Stephanocyclus meneghinianus. B. Cyclotella kingstonii. C–E. Discostella stelligera. D–E. Teratological valves. F. Melosira varians. G. Orthoseira roeseana. H. Aulacoseira ambigua. I. A. brasiliensis. J. A. granulata var. angustissima. K. A. granulata. L–N. A. pusilla. O–Q. A. tenella. R–T. Fragilaria fragilarioides. U–AA. F. radians. X–AA. Teratological valves. AB–AH. F. pectinalis. AE–AH. Teratological valves. AI–AK. F. tenera. AL–AO. F. tenera var. nanana. AN–AO. Teratological valves. AP–AR. F. spectra. AS–AT. Fragilariforma javanica. AU. Ulnaria contracta. AV. U. delicatissima. AW–AZ. U. ulna. AX–AZ. Teratological valves. Scale bars: 10 µm.