| 1. | Lemma summit without a corona | 2 |
| Lemma summit forming a corona | 3 | |
| 2. | Awn 2-3.5 cm long; floret 1.5-2 mm long | *N. trichotoma (NSW VIC TAS) Stipa trichotoma |
| Awn 4.5-9 cm long; floret 2-3 mm long | *N. tenuissima (NSW) | |
| 3. | Floret c. 4 mm long; awn 35-40 mm long | *N. hyalina (NSW VIC) |
| Floret 5.5-10 mm long; awn 45-85 mm long | 4 | |
| 4. | Corona up to 7 mm long | *N. charruana (VIC) |
| Corona up to 2.5 mm long | 5 | |
| 5. | Corona 1.5-2.5 mm long with upper part ciliate | *N. leucotricha (VIC) |
| Corona 0.5-1.5 mm long with upper part spiny | 6 | |
| 6. | Lower glume 8-10 mm long; floret 5.5-6 mm long | *N. megapotamia (NSW) |
| Lower glume 14-18 mm long; floret 6-10 mm long | *N. neesiana (NSW VIC QLD) |