Thismia, Griffith, 1845

Kumar, Pankaj, Gale, Stephan W., Li, Ji-Hong, Bouamanivong, Somsanith & Fischer, Gunter A., 2017, Thismia nigricoronata, a new species of Burmanniaceae (Thismieae, Dioscoreales) from Vang Vieng, Vientiane Province, Laos, and a key to subgeneric classification, Phytotaxa 319 (3), pp. 225-240 : 231

Key to identification of the subgenera, sections and subsections of Thismia

1. Anther thecae connate (subgenus Ophiomeris )..................................................................................................................................2

- Anther thecae free (subgenus Thismia )..............................................................................................................................................4

2. Rootstock vermiform, stem terete, vestigial stem leaves present, mitre present, stamen connective touching or fused to formstami- nal tube .................................................................................................................................................................section Pyramidalis

- Rootstock tuberous, stem sulcate, stem leaves absent, mitre absent, stamen connective free...........................................................3

3. Anthers sagittate with single tip ..............................................................................................................................section Myostoma

- Anthers sagittate with double tip.......................................................................................................................... section Ophiomeris

4. Mitre present.......................................................................................................................................................................................5

- Mitre absent (section Thismia )...........................................................................................................................................................9

5. Outer perianth lobes less than 2 mm long or absent...........................................................................................................................6

- Outer perianth lobes more 2 mm long................................................................................................................................................8

6. Mitre without filiform appendages...................................................................................................................... section Sarcosiphon

- Mitre with filiform appendages..........................................................................................................................................................7

7. Central mitral appendages free from each other....................................................................................................... section Geomitra

- Central mitral appendages fused into a column ................................................................................................section Scaphiophora

8. Outer perianth lobes with filiform appendages ...................................................................................................section Glaziocharis

- Outer perianth lobes without filiform appendages ................................................................................................... section Rodwaya

9. Free perianth lobes of similar shape and size.................................................................................................... subsection Odoardoa

- Free perianth lobes distinctly dissimilar in shape and size........................................................................subsection Brunonithismia