Desmodium

Lima, Laura Cristina Pires, Queiroz, Luciano Paganucci De, Tozzi, Ana Maria Goulart De Azevedo & Lewis, Gwilym Peter, 2014, A Taxonomic Revision of Desmodium (Leguminosae, Papilionoideae) in Brazil, Phytotaxa 169 (1), pp. 1-119 : 16-17

Key to species of Desmodium occurring in Brazil

1. Leaves subtending inflorescence unifoliolate ........................................................................................................................ 2

– Leaves subtending inflorescence trifoliolate........................................................................................................................ 12

2. Prostrate, ascendent or decumbent subshrub, stems virgate .................................................................................................. 3

– Erect subshrub or shrub, stems not virgate ............................................................................................................................ 4

3. Stems tetragonal; fruit a craspedium ........................................................................................................ 8. D. craspediferum

– Stems cylindrical; fruit a lomentum......................................................................................................... 19. D. microcarpum

4. Inflorescence axis shorter than the adjacent leaves...................................................................................... 16. D. juruenense

– Inflorescence axis longer than the adjacent leaves ................................................................................................................ 5

5. Stipules persistent at the base of the inflorescence; fruit articles tortuous............................................................................. 6

– Stipules caducous; articles not tortuous ................................................................................................................................. 7

6. Leaflets membranaceous; articles rhombic ......................................................................................... 18. D. membranifolium

– Leaflets chartaceous, coriaceous, subcoriaceous or papyraceous; articles ovate-elliptic or orbicular .......... 10. D. distortum

7. Loments with orbicular articles.............................................................................................................................................. 8

– Loments with elliptic or obovate-depressed articles ............................................................................................................ 10

8. Flowers up to 6 mm long, corolla purple or violet, ovary glabrous or puberulous................................. 25. D. sclerophyllum

– Flowers more than 8 mm long, corolla lilac or pinkish; ovary tomentose or velutinous....................................................... 9

9. Leaflets up to 1 cm wide, linear or narrowly linear; articles with conspicuous veins .............................. 22. D. polygaloides

– Leaflets more than 3.5 cm wide, elliptic, broadly ovate or ovate; articles with inconspicuous veins ..... 13. D. guaraniticum

10. Leaflets ovate, broadly elliptic or orbicular, abaxial surface velutinous................................................... 4. D. arechavaletae

– Leaflets elliptic, linearornarrowlylinear, abaxial surfacetomentoseor puberulous-uncinate ...........................................11

11. Tertiary veins prominent on the abaxial surface of the leaflets; pedicel 7–9 mm long; fruit stipe ca. 1 mm long; articles elliptic ............................................................................................................................................................... 20. D. pachyrhizum

– Tertiary veins flush with the abaxial surface of the leaflets; pedicel up to 4 mm long; fruit stipe more than 3 mm long; articles obovate-depressed .............................................................................................................................. 21. D. platycarpum

12. Terminal leaflet 3–6(– 9) mm long; inflorescesce fasciculate ........................................................................ 31. D. triflorum

– Terminalleafletmorethan 1 cmlong (except insomespecimensof D. adscendens : 0.5–3.2 cmlong); inflorescencepseudoracemose or paniculate ..................................................................................................................................................... 13

13. Stipules partially fused to each other ................................................................................................................................... 14

– Stipules free from each other ............................................................................................................................................... 15

14. Plant with stolons rooting at the nodes; flowers up to 3.5 mm long; fruit stipe more than 5 mm long............. 5. D. axillare

– Plant without stolons rooting at the nodes; flowers more than 4.5 mm long; fruit stipe up to 2 mm long......15. D. incanum

15. Inflorescence axis shorter than the adjacent leaves.......................................................................................... 6. D. barbatum

– Inflorescence axis longer than the adjacent leaves .............................................................................................................. 16

16. Loment with tortuous articles............................................................................................................................................... 17

– Loment with articles otherwise (not tortuous) ..................................................................................................................... 22

17. Primary bracts persistent; seeds rhombic ................................................................................................... 23. D. procumbens

– Primary bracts caducous; seeds oblong, elliptic or ovate .................................................................................................... 18

18. Stems sulcate; androecium diadelphous; loment with articles dimorphic ....................................................... 12. D. glabrum

– Stems not sulcate; androecium monadelphous; loment with articles uniform..................................................................... 19

19. Stipules not amplexicaul; ovary stipe 2–3 mm long; articles rhombic .......................................................11. D. glabrescens

– Stipules semi-amplexicaul; ovary stipe up to 1 mm long; articles ovate-elliptic or orbicular............................................. 20

16 • Phytotaxa 169 (1) © 2014 Magnolia Press

LIMA ET AL.

20. Ovary tomentose; loment stipe 2–3 mm long ........................................................................................................3. D. album

– Ovary glabrous or puberulous; loment stipe up to 1 mm long............................................................................................. 21

21. Auriculate stipules up to 1.5 mm long; pedicel more than 7 mm long ......................................................... 29. D. tortuosum

– Auriculate stipules more than 3 mm long; pedicel up to 5 mm long ............................................................. 10. D. distortum

22. Prostrate, ascending or decumbent (rarely erect) subshrub, stems virgate .......................................................................... 23

– Erect shrub, stems not virgate .............................................................................................................................................. 29

23. Leaflet venation craspedodromous ...................................................................................................................................... 24

– Leaflet venation brochidodromous or eucamptodromous.................................................................................................... 26

24. Stemssulcate; primarybractsmorethan 6 mm long; lomentwitharticlestriangularorsubtriangular ....28. D. subsericeum

– Stems striate; primary bracts up to 3 mm long; loment with articles oblong or obovate-depressed ................................... 25

25. Stipules persistent; loment 5–8-articulate .............................................................................................................. 2. D. affine

– Stipules caducous; loment 1–3-articulate..................................................................................................34. D. wydlerianum

26. Stipules caducous; flowers 8–12 mm long; androecium monadelphous ............................................................................. 27

– Stipules persistent; flowers 2.5–7 mm long; androecium diadelphous................................................................................ 28

27. Stems glabrescent or sparsely puberulous-uncinate; upper lip of calyx entire; loment 1–2-articulate.............. 24. D. riedelii

– Stems densely uncinate; upper lip of calyx bifid; loment 4–9-articulate......................................................32. D. uncinatum

28. Stipules auriculate; articles narrowly elliptic ............................................................................................... 26. D. scorpiurus

– Stipules not auriculate; articles oblong or rhombic; seeds reniform............................................................. 1. D. adscendens

29. Ovary puberulous or glabrous .............................................................................................................................................. 30

– Ovary tomentose or velutinous ............................................................................................................................................ 31

30. Vexillary stamen partially fused to the apex of the staminal tube; loment stipitate, stipe 2–3 mm long; articles orbicular ............................................................................................................................................... 27. D. subsecundum

– Vexillary stamen partially fused to the base of the staminal tube; loment stipitate, stipe 1–2 mm long; articles ellipitic................................................................................................................................................................ 17. D. leiocarpum

31. Stipules auriculate; loment with articles villous ...............................................................................................14. D. hassleri

– Stipules not auriculate; loment with articles not villous ...................................................................................................... 32

32. Stems glaucous; leaf rachis ca. 1 mm long ...................................................................................................... 9. D. cuneatum

– Stems not glaucous; leaf rachis more than 3 mm long......................................................................................................... 33

33. Stipules triangular; leaflets up to 2.8 cm long......................................................................................... 30. D. triarticulatum

– Stipules ovate; leaflets more than 3.4 cm long..................................................................................................................... 34

34. Infloresccence axillary and/or terminal; loment with the isthmus between articles margina .................... l7. D. cajanifolium

– Inflorescence always terminal; loment with the isthmus between articles central or subcentral ..................... 33. D. venosum