Key to the genus Eulophia group E
Description:
Sepals erect, semi-erect or spreading, longer and usually narrower than the petals.
| 1 | Flowers suberect, facing upwards | 2 |
| 1a | Flowers spreading or nutant | 4 |
| 2 | Sepals 11–13 mm long; lip callus of 3–7 ridges and no papillae | Eulophia rhodesiaca |
| 2a | Sepals 16–19 mm long; lip with a papillose mid-lobe | 3 |
| 3 | Sepals 1–2 mm wide; spur 7–10 mm long; column 5–6 mm long | Eulophia katangensis |
| 3a | Sepals 5 mm wide; spur 10–20 mm long; column 3 mm long | Eulophia saxicola |
| 4 | Leaves well developed at flowering time | 5 |
| 4a | Leaves absent, vestigial or just starting to develop at flowering time | 6 |
| 5 | Leaves 7–12 mm wide; lip with 3–7 lamellae running along the length, but lacking papillae | Eulophia monticola |
| 5a | Leaves 3–8 mm wide; lip with 4 lines of papillae on the mid-lobe | Eulophia hians |
| 6 | Lip lacking papillae on the mid-lobe | 7 |
| 6a | Lip with few to many papillae on the mid-lobe | 9 |
| 7 | Lip 10.5–13 mm long, the mid-lobe with tubercular keels; spur 4–5 mm long, cylindrical with a slightly inflated apex | Eulophia macaulayi |
| 7a | Flowers without the above combination of characters | 8 |
| 8 | Bracts 5–6 mm long; pedicel and ovary 16–17 mm long; lip 12–15 mm long with a crest of thin lamellae on main veins | Eulophia hereroensis |
| 8a | Bracts 12–13 mm long; pedicel and ovary 15–16 mm long; lip 18 mm long with several low ridges down the centre | Eulophia parviflora |
| 9 | Perennating organs pseudobulbous, conical, covered with fibrous sheaths, forming a short chain, mostly subterranean but usually with at least the tip showing above ground | 10 |
| 9a | Perennating organs a tuber or a branched fleshy rhizome, entirely subterranean | 21 |
| 10 | Lateral sepals with basal pouches | Eulophia rolfeana |
| 10a | Lateral sepals lacking basal pouches | 11 |
| 11 | Sepals and petals curled back in a spiral at the tips; papillae of lip 3–4 mm long | Eulophia venulosa |
| 11a | Sepals and petals straight or with the tips reflexed but not curled in a spiral | 12 |
| 12 | Lip mid-lobe deflexed, purple or with a purple margin; leaves lanceolate, usually 5–10 mm wide, starting to develop at flowering time | 13 |
| 12a | Lip not as above; leaves, if present, 1–4 mm wide | 14 |
| 13 | Spur 3–4 mm long, straight or incurved; ovary and pedicel 13–25 mm long; petals 8–8.5 mm long; lip greenish or whitish with a purple margin and white or lilac papillae | Eulophia seleensis |
| 13a | Spur 4–5 mm long, slightly S-shaped; ovary and pedicel 12–18 mm long; petals 8–12 mm long; lip mid-lobe purple with white papillae | Eulophia sabulosa |
| 14 | Spur conical or cylindrical, not swollen at apex | 15 |
| 14a | Spur swollen at apex | 18 |
| 15 | Spur 3.5–4 mm long, cylindrical from the conical lip base, pointing backwards, the tip decurved | Eulophia brenanii |
| 15a | Spur not as above | 16 |
| 16 | Lip lilac or pinkish | Eulophia monotropis |
| 16a | Lip yellow or whitish | 17 |
| 17 | Sepals 8.5–11 mm long; spur straight or upcurved at tip | Eulophia penduliflora |
| 17a | Sepals 15–18 mm long; spur decurved | Eulophia mumbwaensis |
| 18 | Spur straight or upcurved at tip | Eulophia penduliflora |
| 18a | Spur deflexed or decurved | 19 |
| 19 | Sepals 10–15 mm long; flowers brown with a cream lip | Eulophia massokoensis |
| 19a | Sepals 15–20 mm long; flowers not as above | 20 |
| 20 | Sepals spreading, 15–18 mm long, purple-brown; lip yellow, spur reddish | Eulophia mumbwaensis |
| 20a | Sepals erect, 16–20 mm long, golden-brown with maroon lines; lip green and gold, mid-lobe with a bright pink margin | Eulophia obstipa |
| 21 | Leaves vestigial, brown or purple | 22 |
| 21a | Leaves green, but often poorly developed at flowering time | 24 |
| 22 | Sepals erect, linear-spathulate, 15–40 mm long, almost always at least twice as long as the petals; spur 2–5 mm long, conical or cylindrical | Eulophia longisepala |
| 22a | Sepals not erect, linear or oblong, less than one and a half times as long as petals; spur mostly more than 5 mm long | 23 |
| 23 | Flowers brownish or yellow-green, not secund; bracts 9–25 mm long, linear-setose; sepals oblong, 2–3.5 mm wide; plant drying black | Eulophia nyasae |
| 23a | Sepals purple-brown, petals pink-brown or yellow-purple; flowers ± secund; bracts 4–6(12) mm long, not setose; sepals linear, 1.5–2 mm wide; plant drying brown | Eulophia subsaprophytica |
| 24 | Spur geniculate, swollen at apex | Eulophia obstipa |
| 24a | Spur not geniculate slender, not swollen at apex | 25 |
| 25 | Spur 8–10 mm long, straight, slender | Eulophia brenanii |
| 25a | Spur 3–6 mm long, straight or slightly recurved | Eulophia acutilabra |
World Checklist of Monocotyledons. The Board of Trustees of the Royal Botanic Gardens, Kew. Published on the Internet; http://www.kew.org/wcsp/monocots/ accessed 04/08/2019