| 1. | Inflorescence compactly capitate; ovate or conical to globose |
2 |
| Inflorescence spiciform or loosely contracted; linear, lanceolate or oblong |
4 | |
| 2. | Dorsal lemma hairs exceeding base of awns; axilliary spikelets or panicles usually present |
E. caerulescens (NT SA WA) |
| Dorsal lemma hairs shorter than or subequal to base of awns; axilliary spikelets or panicles usually present |
3 | |
| 3. | Awns of lemma distinctly longer than body of lemma; culms usually simple, to 107cm |
E. robustissimus (NT SA WA QLD) E. clelandii |
| Awns of lemma shorter than or subequal to body of lemma; culms often strongly branched, to 66cm |
E. lindleyanus (NT SA WA QLD) E. oblongus, E. pubescens |
|
| 4. | Basal palea cartilaginous, glabrous on body | 5 |
| Basal palea membranous, hairy on body | 6 | |
| 5. | Basal lemma as wide as long; second floret well developed | E. decipiens (NT WA QLD) |
| Basal lemma longer than wide; second floret much smaller than first | E. eremophilus (NT QLD) | |
| 6. | Culms disarticulating at nodes | E. cylindricus (NSW NT SA WA QLD) E. asperatus |
| Culms not disarticulating at nodes | 7 | |
| 7. | Body of basal lemma with appressed hairs on its entire surface; palea keels entirely ciliate |
E. virens (NSW QLD) |
| Body of basal lemma with spreading or erect hairs in lower 1/3-1/2; palea keels partly glabrous |
8 | |
| 8. | Body of basal lemma obscured by dorsal hairs which exceed base of awns |
9 |
| Body of basal lemma partly exposed as dorsal hairs do not or scarcely reach base of awns |
11 | |
| 9. | Florets usually 2, 1 bisexual; upper florets crowded distally |
E. polyphyllus (NSW NT SA WA QLD) |
| Florets usually 3-5, 2-3 bisexual; upper florets not crowded |
10 | |
| 10. | Glumes usually more than 13-nerved; panicle often loosely contracted |
E. avenaceus (NSW VIC NT SA WA QLD) |
| Glumes usually 5-13-nerved; panicle spiciform |
E. intermedius (NSW NT SA WA QLD) | |
| 11. | Body of basal lemma cartilaginous to indurated, nerves scarcely ribbed |
12 |
| Body of basal lemma membranous, nerves thickened |
14 | |
| 12. | Body of basal palea pubescent in lower 1/2-2/3, glabrous above |
E. purpurascens (WA NT) E. glaber, E. planifolius |
| Body of basal palea entirely pubescent | 13 | |
| 13. | Body of basal lemma wider than long, 1.6-2.2mm long; lower glume 9-15-nerved |
E. gracilis (NSW VIC QLD) |
| Body of basal lemma as wide as long, 2.0-3.4mm long; lower glume 7-9-nerved |
E. pallidus (NT WA QLD) | |
| 14. | Basal lemma deeply corrugated by strongly ribbed nerves | E. truncatus (NSW QLD) E. flavescens auct. |
| Basal lemma with thinly ribbed nerves, not corrugated | 15 | |
| 15. | Glumes 3.5-8.0mm long; panicle 1-2cm wide, linear-oblong; plant 30-70cm tall |
E. nigricans (NSW VIC SA QLD) E. arenicola |
| Glumes 3.0-5.6mm long; panicle 1.5-2.5cm wide, ovate or pyramidal; plant 50-110cm tall |
E. robustissimus (NT SA WA QLD) E. clelandii |
Key to Enneapogon derived from Burbidge 1941; Kakudidi, Lazarides and
Carnahan 1988; Weiller & Lazarides 2005
Taxonomic name: