Table 2. Chromosome numbers of 8 Callitriche species counted in this study.
| Taxon | Ref. no.* | Country | Chromosome number (2n) |
| C. stagnalis | C013-12 | Czech Republic | 10 |
| C. cophocarpa | C002-12 | Czech Republic | 10 |
| C. obtusangula | C052-12 | Netherlands | 10 |
| C. ×vigens [C. cophocarpa × C. platycarpa] | C059-08 | Czech Republic | 15 |
| C021-12 | Czech Republic | 15 | |
| C. palustris | C019-12 | Czech Republic | 20 |
| C. platycarpa | C011-12 | Czech Republic | 20 |
| hybrid from Tichá Orlice River | C066-12 | Czech Republic | 29 |
| C. hamulata | C007-12 | Czech Republic | ca 38 |
| C050-13 | USA (introduced) | 38 | |
| C084-13 | Czech Republic | 38 | |
| C094-13 | Czech Republic | 38 |
*For samples details, see Table S2.