Table 1.
Variation in the size of nrDNA operon
| Taxon | Operon lengtha | Estimated copy # |
|---|---|---|
| R. arbuscula (2) | 12.4 kb | 14–21 |
| R. melanophthalma (6) | 11.1–11.2 kb | 12–24 |
| R. novomexicana (1) | 12.4 kb | 16 |
| R. occulta (2) | 12.6–12.7 kb | 27–28 |
| R. parilis (4) | 12.6 kb | 14–36 |
| R. polymorpha (6) | 12.9 kb | 16–28 |
| R. porteri (5) | 11.7–11.8 kb | 19–43 |
| R. shushanii (5) | 14.0–15.9 kb | 9–22 |
| P. peltata (1) | 8.5 kb | 13 |
| R. subdiscrepans (1) | 8.9 kb | 11 |
aIn all specimens, a short region near the 5′ end of the intergenic spacer region (IGS) remained ambiguous due to a region of repeats expanding beyond the libraries’ insert size and is not included in the total operon length