Inflorescence racemose, >1-flowered, terminal; flowers resupinate. Dorsal sepal free, shorter than lateral sepals, erect or reflexed; lateral sepals free, narrow; lateral petals free, longer to shorter than lateral sepals, distinctly clawed, with rounded to ovate lamina. Labellum free, attached at base of column; lamina deeply 3-lobed, with 2 longitudinal keels. Column with stamen and style almost completely free, stubby; column wings almost entirely free, armlike. Column foot absent. Anther erect, parallel to the axis of the filament, persistent. Pollinia 2, soft and mealy. Stigma entire. Rostellum apical.
| | Key to the species | |
| 1 | Lateral lobes of the labellum about as long as or longer than the midlobe | 2 |
| Lateral lobes of the labellum much shorter than the midlobe | 7 |
| 2 | Flowers orange, usually lacking any markings | Diuris aequalis |
| Flowers yellow to golden with reddish brown or blackish markings
Back to 1 | 3 |
| 3 | Labellum with a single callus ridge | Diuris corymbosa |
| Labellum with 2 callus ridges
Back to 2 | 4 |
| 4 | Labellum midlobe obovate when flattened, lateral sepals parallel | Diuris brevissima |
| Labellum midlobe cuneate when flattened, lateral sepals crossed and recurved beneath the labellum
Back to 3 | 5 |
| 5 | Lateral lobes of labellum usually larger than midlobe | Diuris semilunulata |
| Lateral lobes of labellum usually smaller than midlobe
Back to 4 | 6 |
| 6 | Flowers yellow, dotted and spotted with dark markings (mainly coastal) | Diuris maculata |
| Flowers yellow to golden, heavily blotched and suffused with dark markings (mainly inland)
Back to 5 | Diuris pardina |
| 7 | Lateral sepals deflexed, hanging away from the labellum | 8 |
| Lateral sepals directed upward and outward under the labellum
Back to 1 | 26 |
| 8 | Lateral sepals much longer than the petals | 9 |
| Lateral sepals about as long as the petals
Back to 7 | 16 |
| 9 | Flowers white, lilac, mauve or purple | 10 |
| Flowers yellowish to clear yellow, golden or orange
Back to 8 | 13 |
| 10 | Petal claw gradually expanded into the lamina | 11 |
| Petal lamina suddenly expanded at the apex of the claw
Back to 9 | 12 |
| 11 | Labellum spathulate, midlobe ovate-cordate when flattened | Diuris striata |
| Labellum broad-obovate, midlobe circular-flabellate when flattened
Back to 10 | Diuris dendrobioides |
| 12 | Flowers 5–6 cm across, lilac, mauve or purple, petals erect | Diuris punctata |
| Flowers c. 2 cm across, white with lilac or purple markings, petal lamina recurved
Back to 10 | Diuris alba |
| 13 | Flowers yellowish, heavily suffused with mauve and purple | Diuris nebulosa |
| Flowers clear yellow, golden or orange, often with some light markings on the labellum, not heavily suffused
Back to 9 | 14 |
| 14 | Flowers arranged on 1 side of the rachis | Diuris secundiflora |
| Flowers arranged around the rachis
Back to 13 | 15 |
| 15 | Petal claw expanded gradually into the lamina | Diuris tricolor |
| Petal lamina distinctly and suddenly expanded at the apex of the claw
Back to 14 | Diuris punctata |
| 16 | Callus ridges irregularly pubescent towards the apex | Diuris x polymorpha |
| Callus ridges lacking any pubescence
Back to 8 | 17 |
| 17 | Raceme with about 5 prominent, curved, linear bracts | Diuris bracteata |
| Raceme with 2 or 3 bracts, usually not either prominent or curved
Back to 16 | 18 |
| 18 | Labellum callus of a single ridge | Diuris sulphurea |
| Labellum callus of two ridges
Back to 17 | 19 |
| 19 | Flowers bright golden yellow to orange | 20 |
| Flowers lemon yellow to yellow
Back to 18 | 21 |
| 20 | Flowers c. 3.5 cm across | Diuris aurea |
| Flowers c. 2 cm across
Back to 19 | Diuris chrysantha |
| 21 | Flowers more or less nodding | 22 |
| Flowers erect
Back to 19 | 23 |
| 22 | Petal lamina elliptic, labellum midlobe mainly elliptic to obovate when flattened; coastal species flowering July to early Sept | Diuris praecox |
| Petal lamina mainly ovate, labellum midlobe mainly ovate to circular when flattened; inland ranges and tablelands, flowering Sept.–Nov
Back to 21 | Diuris abbreviata |
| 23 | Flowers widely spaced in the raceme | Diuris disposita |
| Flowers closely spaced in the raceme
Back to 21 | 24 |
| 24 | Lateral lobes of labellum 4–7 mm long; raceme usually 30–70 cm high | 25 |
| Lateral lobes of labellum linear to narrow-ovate, 0.8–1.2 mm wide; raceme 10–20 cm high
Back to 23 | Diuris flavescens |
| 25 | Lateral lobes of labellum linear, c. 1 mm wide | Diuris platichila |
| Lateral lobes of labellum narrow-ovate, c. 2–4 mm wide
Back to 24 | Diuris goonooensis |
| 26 | Flowers white to lilac with numerous purple striations | Diuris venosa |
| Flowers yellow to orange
Back to 7 | 27 |
| 27 | Leaves 2; raceme 6–18 cm high; flowers 1 or 2, 1.5–2 cm across | Diuris pedunculata |
| Leaves 3–9; raceme 15–40 cm high; flowers 1–4, 2.5–4 cm across
Back to 26 | Diuris lanceolata |
