Key to the genus Habenaria in Tropical East Africa
Description:
The following key is designed solely to facilitate identification of the East African species and the artificial groups below bear no relation to the natural subdivisions of the genus.
Key to artificial groups

Flowers not resupinate (lip uppermost) Group A
Flowers resupinate (lip on lower side of flower)  
Petals entire, sometimes broadly rounded or angled on the outer margin but never lobed Group B
Petals distinctly 2-lobed, often divided nearly to the base  
Leaves 1 or 2, basal, orbicular or heart-shaped, adpressed to the ground Group C
Leaves neither orbicular nor adpressed to the ground, borne along the stem  
Spur 4 cm. or more in length Group D
Spur 3 cm. or less in length  
Petals incompletely divided, the basal undivided part at least 2 mm. long Group E
Petals divided almost to the base, the united part extremely short  
Dorsal sepal erect, ± surrounding or hiding the column and anther Group F
Dorsal sepal reflexed, the column consequently quite exposed Group G

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 02 May 2020; Flora of Tropical east Africa (Part 1)