Key only partly based on that source.
1 | Spur absent |
1' | Spur present |
2 | Lip with 2 short, narrow, longitudinal calli at the base |
2' | Lip without longitudinal calli at the base |
3 | Spur broadly conical, very short, 1-2 mm long; stigmas 2, placed one on each side of the column at the spur entrance |
3' | Spur conical to filiform, always more than 2 mm long; stigma 1, centrally placed on the front of the column, forming a roof to the spur entrance |
4 | Flowers mostly greenish-yellow, yellow or brownish-yellow |
4' | Flowers pink, purple or violet, rarely white |
5 | Lip conspicuously anthropomorphic, distinctly 3-lobed, mid-lobe divided into 2 linear lobules separated by a mucro or lacinule; lateral lobes linear |
5' | Lip not as above, entire, dentate or lobed; if 3-lobed, lateral lobes not linear |
6 | Lobes of the lip acute, flat, never subfalcate and upcurved; 2 calli present at the base of the lip; leaves often spotted, margins undulate |
6' | Lobes of the lip obtuse, subfalcate, upcurved; calli absent; leaves never spotted, margins not undulate |
7 | Lip entire or weakly dentate |
7' | Lip lobed |
8 | Lip entire, unspotted |
8' | Lip dentate, with reddish or purple streaks and dots |
9 | Lip without dots, streaks or dashes; spur curved forwards in lower part |
9' | Lip with more or less conspicuous dark dots, streaks or dashes; spur curved down- or upwards |
10 | Lateral and dorsal sepals connivent with the petals to form a galea (hood) |
10' | Lateral sepals reflexed or spreading |
11 | Mid-lobe entire |
11' | Mid-lobe divided |
12 | Lobes of lip sharply dentate or serrate; lip with scattered red dots; spur about half as long as ovary |
12' | Lobes of lip nearly entire or weakly dentate; lip without conspicuous dark markings; spur equalling ovary |
13 | Lip with conspicuous dark spots and dots; leaves basal, rosulate, obtuse and mucronate |
13' | Lip with less clear streaks and markings; leaves cauline, acute |
15 | Spur broadened, conical at the mouth, linear towards the apex, longer than the ovary; lip (8-)10-14(-22) mm wide, with many spots |
15' | Spur filiform, not broadened at the mouth, equalling or a little shorter or longer than the ovary; lip 6-7(-10) mm wide, often with 4-6 spots, sometimes more |
14 | Mid-lobe of the lip usually shorter than the lateral lobes; lip 7(-10) x 8(-12) mm; spur broadened and often bilobed at the apex |
14' | Mid-lobe of the lip usually longer than the lateral lobes; lip (8-)9-15 x (10-)11-15(-20) mm; spur of equal width or attenuate at the apex |