Table 4.
Comparison of morphological features of Cocconeisskvortzowii and related species.
| Species | Valve length (μm) | Valve breadth (μm) | Ratio | Striae number in 10 μm | Areolae number in 10 μm | Distribution | References | |
|---|---|---|---|---|---|---|---|---|
| RV | SV | |||||||
| Cocconeisskvortzowii | 8.9–27.0 | 5.6–17.7 | 1.3–2.0:1 | 20–24 | 13–23 | 22–33 (RV) | Lake Baikal | Our data |
| C.placentulavar.skvortzowii | 11–36 | 6.8–22.0 | 1.6–1.8(2.1):1* | 20–30 | 13–20 | 11–13 (SV) | Lake Baikal | Skvortzow 1937; Skabichevsky 1977 |
| C.placentulavar.skvortzowii | 12–24 | 7–14 | 1.7:1* | ~30 | 18 | n.d. | Lake Baikal | Sheshukova 1950 |
| C.skvortzowii | 14–36 | 8–22 | 1.6–1.8:1* | 15–20 | 15–20 | 11–13 | Lake Baikal | Sheshukova 1951 |
| C.disculus (Schumann) Cleve | 20–25 | 11–16 | 1.6–1.8:1* | 22 | 7–9 | n.d. | Europe | Sheshukova 1950, 1951 |
| 10–25 | 7–16 | 1.4–1.6:1* | 20–22 | 6–10 | 18–22 (RV) | Cosmopolitan, Germany | Krammer and Lange-Bertalot 1991; Hofmann et al. 2011; Kulikovskiy et al. 2016b; Lange-Bertalot et al. 2017 | |
| C.diminuta Pant. | 8.5 | 6 | 1.4:1* | 35 | 24 | n.d. | Lake Baikal | Skvortzow 1937 |
| C.disculusvar.diminuta (Pant.) Scheshukova | 7–15 | 5–9 | 1.4–1.7:1* | ~32 | 13 | n.d. | European Russia, Mongolia | Sheshukova 1950, 1951 |
| C.neodiminuta Krammer | 7–18 | 5–9 | 1.4–2:1* | 24–32 | 11–14 (2–4 areolae per stria) | 25–32 (RV) | Germany, Hungary, Switzerland, Ireland | Krammer and Lange-Bertalot 1991; Kulikovskiy et al. 2016b |
| 9.6–19.4 | 6.5–8.0 | 1.5–2.4:1* | ca. 25 | n.d. | n.d. | Poland | Wojtal 2009 | |
| 8–18 | 6–9 | 1.3–2:1* | 24–32 | 11–14 | 25–32 (RV) | Germany, Hungary, Ireland | Romero and Van de Vijver 2011 | |
| 13–17 | 7–10 | 1.7–2:1* | 30 | 13–15 | n.d. | Brazil | Costa et al. 2020 | |
| C.placentulavar.euglypta (Ehrenb.) Grunow | 10–46 | n.d. | n.d. | n.d. | 19–22 | n.d. | Cosmopolitan | Krammer and Lange-Bertalot 1991 |
| 11.0–41.2 | 7.4–26.6 | 1.5:1* | ca. 20 | 20–22 | n.d. | Poland | Wojtal 2009 | |
| C.euglypta Ehrenb. (epitype) | 15.9–29.5 | 9.8–17.7 | 1.5–1.8:1 | 17–22 | 18.5–24 / 20–24 | n.d. | Baltic Sea | Romero and Jahn 2013 |
| 15–30 | 9–18 | 1.7:1* | 17–22 | 18–24 | n.d. | Cosmopolitan | Kulikovskiy et al. 2016b | |
| 15–45 | 9–28 | 1.5–1.8:1 | 17–22 | 18–24 | n.d. | n.d | Lange-Bertalot et al. 2017 | |
| 13.4–29.5 | 8.3–16.6 | 1.6–1.8:1* | 19–24 | 22–24 | n.d. | Brazil | Costa et al. 2020 | |
| C.placentulavar.lineata (Ehrenb.) Van Heurck | 30 | 18 | 1.7:1* | n.d. | 24 | n.d. | Lake Baikal | Skvortzow 1937 |
| 40–70 | 30–40 | 1.3–1.8:1* | n.d. | n.d. | n.d. | Russia, Europe | Sheshukova 1951 | |
| 10–80 | n.d. | n.d. | n.d. | 16–23 | n.d. | Cosmopolitan | Krammer and Lange-Bertalot 1991 | |
| 14.0–25.2 | 10.5–14.0 | 1.3–1.8:1* | 22.0–23.5 | 20–22 | n.d. | Poland | Wojtal 2009 | |
| 11–42 | 7–28 | 1.5–1.6:1* | 15–24(30) | n.d. | n.d. | North Russia | Genkal and Vekhov 2007 | |
| C.lineata Ehrenb. (epitype) | 18.6–22.7 | 6.4–13.1 | 1.6–2.4:1 | 20–28 | (7)10–15 / 12–20 | 16–24(26) (SV) | Faroer Islands, Denmark | Romero and Jahn 2013 |
| C.lineata | 18–23 | 6–14 | 1.6–3:1* | 20–28 | 10–15 | 16–24 (SV) | Cosmopolitan | Kulikovskiy et al. 2016b |
| 16–80 | 6–35 | 1.6–2.4:1 | 20–28 | 10–15 | 16–24 (SV) | Europe | Lange-Bertalot et al. 2017 | |
| 12.7–19.6 | 7.9–10.9 | 1.6–1.8:1 | 21–22 | 25–32 | n.d. | Brazil | Costa et al. 2020 | |
| 19.1–22.8 | 9.4–12.6 | 1.6–2.2 | 18–24 | 22–28 | 25–28 (RV), 12–18 (SV) | Korea | Jahn et al. 2017 | |
| C.placentulavar.pseudolineata Geitler | 7.5–38.0 | n.d. | n.d. | n.d. | 13–20(22) | n.d. | n.d. | Krammer and Lange-Bertalot 1991 |
| 7.5–38.0 | n.d. | n.d. | 16–20(22) | 20–23 | n.d. | n.d. | Romero and Van de Vijver 2011 | |
| C.pseudolineata (Geitler) Lange-Bert. | 7.5–38.0 | 6–18 | 1.3–2.1:1* | 20–23 | 13–18(20) | 16–20(22) (SV) | Europe | Hofmann et al. 2011; Lange-Bertalot et al. 2017 |
| 12.5–23.0 | 8–18 | 1.3–1.6:1* | 23–24 | 13–15 | n.d. | Poland | Wojtal 2009 | |
| 16–32 | 8–14 | 2–2.3:1* | 23–26 | 12–22 | 23–28 (RV) | n.d. | Werum and Lange-Bertalot 2004 | |
| C.pseudothumensis Reichardt | 11.5–13.5 | 8.2–9.5 | 1.4:1* | 35–40 | 10–20 | 10–20 (RV) | Europe, France, Germany, Switzerland | Reichardt 1982; Romero and Van de Vijver 2011 |
| 11.5–13.5 | 8.2–9.5 | 1.4:1* | 35–40 | 10–12 | n.d. | France, Europe | Krammer and Lange-Bertalot 1991; Hofmann et al. 2011; Lange-Bertalot et al. 2017 | |
| 9–15 | 6.5–11.0 | 1.4:1* | 35–40 | 10–14 | n.d. | Holarctic | Kulikovskiy et al. 2016b | |
| C.thumensis Ant. Mayer | Up to 10 | 5–6 | n.d. | 15–16 | 15–16 | n.d. | North European Russia, Europe | Sheshukova 1950, 1951 |
| C.neothumensis Krammer | 6.5–13.0 | 4.0–8.3 | 1.6:1* | 28–36 | 16–25 | 34–37 (RV) | Cosmopolitan, Germany | Krammer and Lange-Bertalot 1991; Hofmann et al. 2011; Kulikovskiy et al. 2016b; Lange-Bertalot et al. 2017 |
| 11.2–12.2 | 7.0–7.4 | 1.6:1* | 23 | 26 | n.d. | Brazil | Costa et al. 2020 | |
| 8.0–10.6 | 4.4–8.0 | 1.3–1.8:1* | 25–30 | 28 | n.d. | North Russia | Genkal and Vekhov 2007 | |
* – our calculations on illustrations; n.d. – no data.