Key to the Nebela collaris-tincta group
| 1 | Test wider than long | 2 |
| – | Test longer than wide | 3 |
| 2 | L. 72–111 µm, B. 90–133 µm, strongly flattened, with short neck | N. flabellulum |
| – | Smaller species, L. 60 µm, B. 70 µm, compressed, without neck | N. acolla |
| 3 | Test > 100 µm | 4 |
| – | Test < 100 µm | 6 |
| 4 | Test compressed | 5 |
| – | Test not compressed | N. golemanskyi |
| 5 | Test with lateral ridge, wide ovoid, with wide linear aperture 24–27 µm | N. aliciae |
| – | Test without lateral ridge, pyriform, with very short (2.7 ± 0.9 µm high or almost absent) neck, with aperture slightly or strongly curved, or sometimes linear, 28–32 µm | N. bohemica |
| 6 | With protruding neck and narrow aperture 19–23 µm, up twisted | 7 |
| – | With short neck (4.6 ± 0.2 high), with linear wide aperture 24–26 µm | 9 |
| 7 | Aperture curved | 8 |
| – | Aperture not curved | N. pechorensis |
| 8 | L. 80–89 µm, B. 53–65 µm | N. guttata |
| – | L. 67–78 µm, B. 50–62 µm | N. gimlii |
| 9 | Test ovoid or elongated elliptic, L/B = 1.3–1.4 | N. tincta |
| – | Test rounded, L/B = 1.2–1.3 | N. rotunda |
Modified after Kosakyan et al., 2012