Cheirostylis

Key to species of Cheirostylis View in CoL in Thailand (adopted from Pedersen, 2011)

1. Foliage leaves scattered along the stem ........ 2

1. Foliage leaves assembled in a loose to dense rosette ............................................................. 3

2. Lamina of longest leaf less than 1.2 cm long; synsepal less than 7 mm long; hypochile inside with one, basally 2- or 3-branched appendage on either side; epichile bilobed with slightly erose-dentate to erose-crenulate lobes ...........

C. pusilla View in CoL

2. Lamina of longest leaf more than 1.2 cm long; synsepal more than 7 mm long; hypochile inside with a longitudinal row of 15–20 appendages on either side; epichile transversely elliptic, coarsely 7- to 9-dentate

C. octodactyla

3. Petals free from the synsepal along their whole length; apices protruding from the lateral sinuses of the synsepal ................................... 4

3. Petals adnate or adherent to the synsepal along their whole length or nearly so; apices not protruding from the lateral sinuses of the synsepal (occasionally protruding in C. spathulata View in CoL ) ....................................................... 5

4. Apical part of labellum emarginate to deeply bilobed (lobes often unequal) with slightly erose to dentate-laciniate margin; basal part inside with a short row of 3–6 papilla-like appendages on either side .......... C. thailandica View in CoL

4. Apical part of labellum obtuse to subacute with entire margin; basal part devoid of appendages .......................................... C. takeoi View in CoL

5. Ovary glabrous ......................... C. moniliformis View in CoL

5. Ovary glandular-pubescent (sometimes sparsely so) .................................................................... 6

6. Margins of epichile subentire to erose-crenulate or irregularly dentate .................... 7

6. Margins of epichile deeply laciniate or coarsely dentate ............................................................ 8

7. Synsepal less than 6 mm long; epichile transversely oblong to moderately bilobed (i.e., entire or cleft for up to about half of its length) ............................................. C. montana View in CoL

7. Synsepal more than 6 mm long; epichile deeply bilobed (i.e., cleft in its whole length or very nearly so) .............................. C. spathulata View in CoL

8. Synsepal more than 9 mm long; hypochile inside with two rows of numerous papillae; epichile lobes deeply laciniate ....... C. griffithii View in CoL

8. Synsepal less than 9 mm long; hypochile inside with two rows of 2–4 papillae; epichile lobes coarsely dentate .............................................. 9

9. Leaves assembled in a dense, basal rosette; Inflorescence more than 5 cm long; rachis moderately pubescent with short glandular hairs. Synsepal not saccate. Epichile flat in front view ( i.e., lobes widely spreading) .......... C. yunnanensis View in CoL

9. Leaves assembled in a loose, sub-basal rosette; Inflorescence less than 5 cm long; rachis densely pubescent with long glandular hairs. Synsepal distinctly saccate. Epichile U-shaped in front view ( i.e., lobes moderately spreading) .................................... C. tortilacinia View in CoL