Key to Habenaria artificial groups in Flora Zambesiaca regionen

1a Basal leaves 1–2, orbicular or heart-shaped, appressed to ground Habenaria group A
1b All leaves borne along stem, not appressed to ground 2
2a Petals entire Habenaria group B
2b Petals 2-lobed 3
3a Spur 3.5 cm long or more Habenaria group C
3b Spur less than 3.5 cm long 4
4a Petals incompletely divided, at least the basal c. 5 mm undivided Habenaria group D
4b Petals 2-lobed almost to base 5
5a Dorsal sepal erect, more or less surrounding the column Habenaria group E
5b Dorsal sepal reflexed, leaving column exposed Habenaria group F

References:
WCSP (2020). 'World Checklist of Selected Plant Families. Facilitated by the Royal Botanic Gardens, Kew. Published on the Internet; http://wcsp.science.kew.org/ Retrieved 13 April 2020.