AFRICAN

ORCHIDS

Key to the genus Habenaria in South Africa
Kraenzlin (1893) monographed this large and diverse genus and recognized a number of sections, a few of which have since been accorded generic rank by some authors (among the African genera these are Bonatea, Centrostigma, Platyco-ryne and Kryptostoma). A new revision, on a worldwide basis, is required to ascertain sectional limits and to update the nomenclature.

1a Petals entire, sometimes broadly rounded or angled on the outer margin but not lobed 2
1b Petals distinctly bipartite, often divided nearly to the base 10
2a Lip tripartite 3
2b Lip undivided, at most with 2 short filamentous lateral processes at the base 9
3a Leaves cauline, ovate; spur 1.5 mm long, subglobose Habenaria petitiana
3b Leaves otherwise; spur 8-30 mm long, slender 4
4a Flowers pedicellate; spur with a tooth at the mouth; leaves not grading into the bracts 5
4b Flowers subsessile; spur without such a tooth; leaves grading into the bracts 6
5a Leaves 2-3, basal; stigmas and anther canals porrect, exposing a prominent tooth in the mouth of the spur Habenaria arenaria
5b Leaves numerous, cauline; stigmas and anther canals sub-erect, concealing the small tooth in the mouth of the spur Habenaria filicornis
6a Basal leaf sheaths horizontally barred with black; bracts and sepals hispid; lip midlobe porrect 7
6b Basal leaf sheaths immaculate; bracts and sepals glabrous; lip midlobe erect in front of the gynostemium 8
7a Spur c. 10 mm long, subequal to the ovary; lip side lobes longer than the midlobe; rostellum arms simple Habenaria ciliosa
7b Spur 15-25 mm long, at least 1.5 times as long as the ovary; lip side lobes shorter than the midlobe; rostellum arms
lobed adaxially near the base
Habenaria pseudociliosa
8a Leaves linear, spreading, then erect; sepals spreading; spur 6-11 mm long, shorter than the ovary... Habenaria bicolor
8b Leaves narrowly elliptic, adpressed to the stem; sepals deflexed; spur 16-30 mm long, longer than the ovary Habenaria laevigata
9a Petals obliquely lanceolate, acute; median sepal 5 mm long; spur 8 mm long; lip simple Habenaria anguiceps
9b Petals elliptic to almost orbicular, rounded; median sepal 8-12 mm long; spur 15-65 mm long; lip with filamentous
side lobes
Habenaria epipactidea
10a Leaves several, cauline, neither orbicular nor adpressed to the ground 11
10b Leaves I or 2, basal, orbicular or cordate, adpressed to the ground 28
11a Lateral sepals horizontally spreading 12
11b Lateral sepals deflexed, adpressed to the ovary 15
12a Lip side lobes abruptly divergent, horizontally spreading, the lip cruciform; lower petal lobe longer than the upper;
stigmatic surface apical or dorsal; leaves lanceolate
13
12b Lip side lobes gradually divergent, not horizontal; lower petal lobe shorter or subequal to the upper; stigmas compressed,
receptive surface lateral; leaves elliptic
14
13a Spur recurved, inflated apically; lip lobes subequal, pubescent at the base Habenaria rautaneniana
13b Spur straight, not inflated apically; lip midlobe shorter, lobes glabrous Habenaria pasmithii
14a Upper petal lobe linear, subequal to the lower; spur 20 mm long, subequal to the ovary plus pedicel; central rostellum lobe
linear, projecting
Habenaria transvaalensis
14b Upper petal lobe ovate, longer than the lower; spur 30-40 mm, much longer than the ovary plus pedicel; central rostellum
lobe vestigial
Habenaria barbertoni
15a Lower petal lobes linear, horn-like, spreading forwards and curved upwards 16
15b Lower petal lobes not linear and horn-like 18
16a Spur c. 8 mm long Habenaria stenorhynchos
16b Spur over 15 mm long 17
17a Lip side lobes widest some distance above the base; spur 15-25 mm long; stigmatic arms 3-8 mm long Habenaria cornuta
17b Lip side lobes linear, tapering; spur 30-50 mm long; stigmatic arms 8-12 mm long Habenaria clavata
18a Median sepal erect; petals glabrous 19
18b Median sepal reflexed, exposing the gynostemium; upperpetal lobe puberulous 21
19a Leaves narrowly oblong, suberect, papery when dry Habenaria tridens
19b Leaves broadly lanceolate to oblong, spreading, membranous when dry 20
20a Lower petal lobe slightly longer than the upper, 4-6.5 mm long; lip lobes subequal, 4-6.5 mm long; spur somewhat
thickened in the middle
Habenaria malacophylla
20b Lower petal lobe much shorter than the upper, 0.4-2.5 mm long; lip side lobes vestigial, 0.4-1 mm long; spur filiform,
tapering
Habenaria culveri
21a Anther canals shorter than the anther loculi; stigmas short, I -3 mm long 22
21b Anther canals distinctly longer than the anther loculi; stigmas longer, 3.5-7 mm long 24
22a Lower petal lobe linear-lanceolate, much longer than the upper; median sepal c. 3 mm long; bracts glabrous; leaves linear Habenaria woodii
22b Lower petal lobe broadly to narrowly ovate, at most subequal to the upper; median sepal 3-7 mm long; bracts
glandular-pubescent; leaves lanceolate
23
23a Spur 8-15 mm long, tapered from a widened mouth; median sepal 3-5 mm long; anther canals incurved Habenaria dives
23b Spur 20-40 mm long; median sepal 6-7 mm long; anther canals adpressed throughout their length Habenaria falcicornis
24a Ovary c. 5 mm long, c.¼ the length of the very slender pedicel; spur very slender in the basal part, much inflated apically Habenaria ichneumonea
24b Ovary 6-15 mm long, usually more than ⅓ the length of the pedicel 25
25a Lower petal lobe oblong-lanceolate, obtuse, less than 2x as long as the upper Habenaria humilior
25b Lower petal lobe narrowly lanceolate, tapering, acute, usually more than 2x as long as the upper 26
26a Spur sharply incurved and geniculate, 10-15 mm long; pedicels horizontal and ovary sharply deflexed Habenaria schimperiana
26b Spur gently incurved, 20-30 mm long; pedicel plus ovary suberect, not angled 27
27a Leaves cauline, stem robust, 0.5-1.2 m tall; spur more or less straight, twisted through 180°, 20-30 mm long; lower
petal lobe lanceolate, 1.5-2 mm wide at the base; pedicel and ovary subequal; sepals glabrous
Habenaria nyikana
27b Leaves subradical, stem fairly slender, 130-400 mm tall; spur incurved, not twisted, c. 20 mm long; lower petal lobe
linear-lanceolate, c. I mm wide; ovary ⅔ length of the pedicel; sepals glandular-pubescent
Habenaria galpinii
28a Spur 50 mm or more long; anther 4.5-9 mm tall; stigmas 5-10 mm long, receptive at the tips 29
28b Spur less than 45 mm long; anther 2-3 mm tall; stigmas 1-3 mm long, receptive for most of their length above 30
29a Median sepal 7-11 mm long; spur 50-75 mm long Habenaria subarmata
29b Median sepal 11-16 mm long; spur 80-180 mm long Habenaria armatissima
30a Upper petal lobe ovate, rounded; rostellum projecting in front of the gynostemium, acutely trifid near the apex Habenaria trilobulata
30b Upper petal lobe narrowly oblong, acute; rostellum not projecting forwards, lateral lobes distinct 31
31a Lower petal lobe 5-6x as long as the upper; lip side lobes more than 2x as long as the midlobe; spur 30-45 mm long Habenaria kraenzliniana
31b Lower petal lobe at most 2x as long as the upper; lip side lobes less than 2x as long as the midlobe; spur 8-24 mm long 32
32a Spur expanded at the mouth; lower petal lobe much shorter than the upper; lip side lobes shorter than the midlobe Habenaria dregeana
32b Spur not expanded at the mouth; petal lobes subequal or the lower longer; lip lobes subequal or the side lobes longer 33
33a Spur 8-11 mm long; stigmas 1-1.8 mm long, not reaching to the lip sinuses; pedicels suberect; median sepal erect Habenaria Iithophila
33b Spur 12-24 mm long, usually twisted; stigmas 2-3 mm long, extending to the lip sinuses; pedicels c. horizontal; median
sepal reflexed
34
34a Lower petal lobe 11-15 mm long, 2x as long as the upper; lip side lobes 10-15 mm long Habenaria tysonii
34b Lower petal lobe 5-9 mm long, less than 1.5x as long as the upper; lip side lobes 7-10 mm long Habenaria mossii

References:
Orchids of Southern Africa by H. P. Linder & H. Kurzweil, A. A. Balkema; 1 edition (September 30, 1999); 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 27. April 2020