Odontochilus

M., Sun, Y., Jin, J., Huang, P., Kumar & Tian, H. Z., 2021, Odontochilus putaoensis (Orchidaceae), a new record and key to the genus for China, Rheedea 31 (3), pp. 200-205 : 203-204

Key to the species of Odontochilus in China

1. Plants holomycotrophic, leafless ................. 2

1. Plants autotrophic, leafy............................... 4

2. Flowers resupinate; lip white ........................ ................................................ O. saprophyticus

2. Flowers not resupinate; lip orange or light yellow ............................................................ 3

3. Dorsal sepal c. 7 × 4 mm; lip orange-yellow, with a pair of elongate introrse lobules at the epichile lobes .................................. O. poilanei

3. Dorsal sepal c. 4 × 2 mm; lip light yellow, without a pair of elongate introrse lobules at the epichile lobes ................ O. guangdongensis

4. Flowers non-resupinate ............. O. napoensis

4. Flowers resupinate ........................................ 5

5. Sepals connate in their basal part; column without lamellate appendages ...................... 6

5. Sepals separate; column with a pair of lamellate appendages .................................................... 7

6. Sepals shallowly connate at the base .............. ............................................... O. yakushimensis

6. Sepals connate for about half of their length ..................................................... O. nakaianus

7. Leaves usually less than 1.5 cm in length; anther apex not twisted ............................................ 8

7. Leaves usually more than 1.5 cm in length; anther apex twisted ..................................... 12

8. Epichile entire, occasionally slightly emarginate; calli subquadrate ....................... 9

8. Epichile obviously bifid; calli transversely elliptic or sub-oblong ................................. 10

9. Petals ovate; lip c. 5 mm long, epichile obcordate or obovate, 1–1.5 mm wide .......... ........................................................ O. chinensis

9. Petals ovate-oblong; lip c. 7 mm long, epichile transversely oblong to obtriangular, 3–3.5 mm wide .............................................. O. japonicus

10. Sepals 8–9 mm long; petals oblique; lip 10–12 mm long; calli suboblong, bidentate ............. .......................................... O. drymoglossifolius

10. Sepals 5–7 mm long; petals not oblique; lip 7– 8 mm long; calli transversely elliptic, apex obtuse, truncate or slightly concave........... 11

11. Petals broadly ovate, urceolate, c. 3.5 mm wide; mesochile entire .......................... O. urceolatus

11. Petals oblanceolate-oblong, c. 2 mm wide; mesochile serrulate .......................... O. pumila

12. Leaves less than 2 cm long.......................... 13

12. Leaves more than 2 cm long ...................... 14

13. Lip without reddish purple spots, mesochile with short irregular teeth ................. O. crispus

13. Lip with reddish purple spots, mesochile with fimbriate filaments .................. O. nanlingensis

14. Lip curved upwards ................... O. putaoensis

14. Lip stretched forward .................................. 15

15. Lip yellow .................................................... 16

15. Lip white or light yellow ............................ 18

16. Ovary pubescent; sepals and petals with a deep purplish red stripe on each side of mid-vein; lip yellow tinted with purplish red .... O. clarkei

16. Ovary glabrous or pubescent in its distal part; sepals yellowish green; petals whitish green; lip yellow ..................................................... 17

17. Without two flesh appendages on either side of the column; rostellum bifid ....... O. lanceolatus

17. With two flesh appendages on either side of the column; rostellum twisted .... O. bisaccatus

18. Sepals and petals with conspicuous dark-green or brownish-green patches............. O. tashiroi

18. Sepals and petals without patches or with weaker dark-green patches......................... 19

19. Sepals and petals without patches; mesochile margin with slender filaments ......... O. elwesii

19. Sepals and petals with weak dark-green patches; mesochile margin with short and wide irregular teeth .............................................. 20

20. Ovary apex straight; lateral sepals spreading ............................................................ O. tortus

20. Ovary apex downcurved; lateral sepals not spreading...................................................... 21

21. Sepals and petals with dark green tessellation; mesochile have short irregular teeth .............. ...................................................... O. brevistylis

21. Sepals and petals without dark green tessellation; mesochile have long fringes ....... ............................ O. brevistylis subsp. c andidus