Crotalaria, Linnaeus, 1753

Flores, Andréia Silva & Tozzi, Ana Maria Goulart De Azevedo, 2018, A synopsis of the genus Crotalaria (Leguminosae) in Brazil, Phytotaxa 346 (1), pp. 31-58 : 32-33

Key to the Brazilian species of Crotalaria

1. Leaves simple ................................................................................................................................................................................... 2

– Leaves 1-foliolate or digitately 3–(4–5)-foliolate ........................................................................................................................... 23

2. Flowers with calyx 2-lipped .............................................................................................................................................................. 3

– Flowers with calyx 5-subequally lobed........................................................................................................................................... 21

3. Branches glabrous or glabrescent...................................................................................................................................................... 4

– Branches hairy ................................................................................................................................................................................... 5

4. Bracts 6–20 mm long, foliaceous or oval-lanceolate ................................................................................................... 27. C. paulina

– Bracts 5–7 mm long, linear to linear-lanceolate. .................................................................................................... 40. C. vespertilio

5. Branches and leaves pilose ............................................................................................................................................................... 6

– Branches and leaves pubescent, puberulous or canescent, never pilose .......................................................................................... 9

6. Raceme terminal, 6–20-flowered ...................................................................................................................................................... 7

– Raceme opposite to leaves and up to 5-flowered .............................................................................................................................. 8

7. Peduncle 1–2 cm long; bracts and bracteoles ovate-lanceolate to foliaceous ........................................................... 6. C. flavicoma

– Peduncle 4.5–12 cm long; bracts and bracteoles linear or linear-lanceolate ........................................................... 36. C. tweediana

8. Branches prostrate to decumbent; leaves suborbicular or ovate; internodal stem wings usually absent or up to 1.3 cm long; peduncle 3.5–11.5 cm long ...................................................................................................................................................... 11. C. hilariana

– Branches erect to ascending; leaves oblong, oblong-elliptic or elliptic; internodal stem wings (0.8–) 1–5 cm long; peduncle 2–4.5 cm long ........................................................................................................................................................................ 2. C. balansae

9. Branches ribbed; ovary and legume velvety tomentose ............................................................................................... 15. C. juncea

– Branches not ribbed; ovary and legumes glabrous.......................................................................................................................... 10

10. Bracts 2–5 mm wide, foliaceous or ovate-lanceolate ..................................................................................................................... 11

– Bracts up to 2 mm wide, elliptic, linear-lanceolate or linear........................................................................................................... 12

11. Branches puberulous, leaves elliptic ......................................................................................................................... 7. C. goiasensis

– Branches canescent or densely pubescent; leaves oblong, oblanceolate, obovate or oblong-elliptic ....................... 19. C. martiana

12. Internodal stem wings 0.5–2 cm wide, projections falcate or falcate-acuminate ........................................................................... 13

– Internodal stem wings absent or when present, up to 0.5 cm wide, projections obtuse, auriculate, triangular or absent .............. 15

13. Herbs or subshrub up to 0.5 m high; the standard petal up to 0.8 cm long ............................................................. 33. C. stipularia

– Subshrub or shrub 1–3 m high; the standard petal 1.2–2.5 cm long .............................................................................................. 14

14. Stipules linear or triangular; leaf with attenuate base ................................................................................................ 25. C. otoptera

– Stipules absent; leaf with cuneate base ......................................................................................................................... 14. C. irwinii

15. Plants up to 1m high, and racemes with up to 3-flowered ............................................................................................................. 16

– Plants usually higher, up to 2, 5 m high, and racemes with (3–)5–20-flowered ............................................................................. 17

16. Leaves ovate-lanceolate, narrowly lanceolate or elliptic; keel petal 10–15 mm long ................................................ 38. C. velutina

– Leaves linear or linear-elliptic; keel petal 8–9 mm long .......................................................................................... 31. C. sagittalis

17. Internodal stem wings present, mainly near the inflorescences ..................................................................................................... 18

– Internodal stem wings absent ......................................................................................................................................................... 20

18. Stem single or few branched; bracts 2–3 mm long ....................................................................................................... 28. C. pilosa

– Stem densely branched; bracts 5–20 mm long ............................................................................................................................... 19

19. Branches pubescent; keel petals up to 1.6 cm long ................................................................................................... 4. C. breviflora

– Branches densely pubescent or canescent; keel petals 1.8–2.3 cm long ............................................................ 34. C. subdecurrens

20. Raceme 5–12 cm long, 3–7 flowers; leaves elliptic, widely elliptic, ovate, rarely linear ....................................... 9. C. grandiflora

– Raceme 11–26 cm long, 7–20 flowers; leaves oblong or oblong-elliptic ..................................................................... 23. C. nitens 21. Stipules linear up to 2 mm long, deciduous .................................................................................................................. 29. C. retusa

– Stipules ovate, suborbicular or semi-lunate, 4–9 mm long, persistent ........................................................................................... 22

22. Flowers with pale blue corolla; bracts linear-lanceolate ......................................................................................... 39. C. verrucosa

– Flowers with yellow corolla; bracts ovate, broad ................................................................................................... 32. C. spectabilis

23. Leaves unifoliolate ................................................................................................................................................ 37. C. unifoliolata

– Leaves digitately 3–(4–5)-foliolate ................................................................................................................................................ 24

24. Keel spirally twisted, standard-appendages restricted to the blade................................................................................................. 25

– Keel not twisted, standard-appendages extending from the blade to the claw ............................................................................... 26

25. Petioles 3–6 mm long; standard petal up to 5 mm long ........................................................................................... 41. C. virgulata

– Petioles 15–34 mm long; standard petal 12–14 mm long .................................................................................. 18. C. longirostrata

26. Calyx with lobes twice to five times as long as the tube; receptacle campanulate ........................................................................ 27

– Calyx with lobes shorter than or of the same length of the tube; receptacle truncate .................................................................... 39

27. Racemes with caducous bracts (usually present in floral buds) ..................................................................................................... 28

– Racemes with persistent bracts ....................................................................................................................................................... 30

28. Stipules foliaceous, oblong-falcate, persistent; wing petals up to 1cm long; legumes 1.5–2 cm long ...................... 8. C. goreensis

– Stipules linear or subulate, caducous; wing petals 1.5–2 cm long; legumes 2.5–4 cm long .......................................................... 29

29. Bracts 1–4 mm long, straight; inflorescences lax ................................................................................................ 20. C. maypurensis

– Bracts 5–12 mm long, curled; inflorescences congest ................................................................................................. 21. C. micans

30. Calyx with lobes four to five times as long as the tube ............................................................................................. 5. C. claussenii

– Calyx with lobes two to three times as long as the tube.................................................................................................................. 31

31. Keel petals lanate on the upper margin; petiole usually longer than the terminal leaflet ............................................. 13. C. incana

– Keel petals glabrate or ciliate on the upper margin; petiole usually shorter than the terminal leaflet ........................................... 32

32. Wings shorter than the keel ............................................................................................................................................. 16. C. laeta

– Wings as long as or longer than the keel ........................................................................................................................................ 33

33. Keel petals 0.6–0.8 cm long .................................................................................................................................. 3. C. brachycarpa

– Keel petals 0.8–1.6 cm long ........................................................................................................................................................... 34

34. Petioles up to 1cm long .................................................................................................................................................................. 35

– Petioles 1–7.5 cm long ................................................................................................................................................................... 36

35. Leaflets elliptics or ovate, lanate or villous; bracts 4–5 mm long ................................................................................ 10. C. harleyi

– Leaflets oblanceolate or oblong-elliptic, sericeous; bracts 2–3 mm long ................................................................... 30. C. rufipila

36. Branches glabrous, glabrescents or finely pubescent ..................................................................................................................... 37

– Branches villous, velutinous, pubescent, sericeous, woolly or lanate ............................................................................................ 38

37. Wings 0.9 –1.3 cm long; legumes brown, 2–3.2 × 0.6–0.9 cm .................................................................................. 42. C. vitellina

– Wings 1.3–1.8 cm long; legumes black, 3.2–4.3 × 1.1–1.4 cm .................................................................................. 22. C. miottoae

38. Leaflets elliptic or widely elliptic, sericeous; inflorescences usually lax ............................................................ 12. C. holosericea

– Leaflets orbicular, widely ovate to widely elliptic, villous or velutinous; inflorescences crowded ......................... 1. C. bahiaensis

39. Bracts caducous; wings shorter than the keel; legumes brown at maturity .................................................................. 26. C. pallida

– Bracts persistent; wings as long as or longer than the keel; legumes brown or black at maturity..................................................40

40. Flowers up to 1 cm long; legumes 0.4–0.8 cm broad, cylindrical curved at the apex ........................................... 17. C. lanceolata

– Flowers 1.2–1.9 cm long; legumes 0.8–1.5 cm broad, obovate or cylindrical ............................................................................... 41

41. Keel petals 1.5–1.7 cm long; wings 1.4–1.8 cm long; legume sessile 1–1.5cm wide ........................................... 24. C. ochroleuca

– Keel petals 1.2–1.5 cm long; wings 1.3–1.5 cm long; legume shortly stipitate 0.8–1 cm wide ............................. 35. C. trichotoma