The genus Eulophia in Flora Zambesiaca area (Zimbabwe, Zambia, Malawi, Mozambique, Botswana, Zambezi Region of Namibia and the Caprivi Strip)
Key to artificial groups in the genus Eulophia

1 Saprophytic plants with no true leaves; flowering stems fleshy, yellow or pale brown lacking any tinge of green  Group A
1a Autotrophic oi semi-saprophytic plants; leaves may be absent or vestigial at flowering time. but then stem not fleshy; flowering stems green to purple-brown 2
2 Plants with large conical, ovoid or cylindrical pseudobulbs, mostly above ground and not covered with fibrous sheaths  Group B
2a Plants with corms, fleshy rhizomes or pseudobulbs which are mostly below ground and/or covered with brown fibrous sheaths  3
3 Petals suborbicular or broadly ovate or orbicular, rounded at the apex and projecting over the column, longer and much broader than the sepals and usually of a different colour  Group C
3a Petals and sepals similar in size, shape and colour, or sepals much longer than the petals  4
4 Sepals and petals all projecting forwards so that flower is ± bell-shaped and often nutant; all flower parts of similar colour although lip may have a dark blotch Group D
4a Flowers not bell-shaped; lip usually of a different colour from sepals and petals  5
5 Sepals erect, semi-erect or spreading, longer than petals and usually narrower  Group E
5a Sepals and petals of similar length and width; if sepals longer, then flowers not opening wide  Group F

Flora Zambesiaca, Volume Eleven Part Two, London 1998