Apios

Tutin, T. G., Heywood, V. H., Burges, N. A., Moore, D. M., Valentine, D. H., Walters, S. M. & Webb, D. A., 1981, Flora Europaea. Volume 2. Rosaceae to Umbelliferae, Cambridge University Press : 80-83

LXXXI. LEGUMINOSAE1

Trees, shrubs or herbs. Leaves alternate, rarely opposite, simple to 2-pinnate, stipulate. Flowers usually hermaphrodite, usually 5-merous. Sepals usually united. Petals free or somewhat connate. Stamens usually 10, sometimes less than 10 or numerous. Ovary a single unilocular carpel; style 1. Fruit a dehiscent, 2-valved or indéhiscent, occasionally lomentaceous legume. Seeds usually without endosperm. A large number of species, both native and introduced,

are cultivated for food, for fodder and for ornament. Those most frequently utilized as food are to be found in Apios , Arachis, Cicer, Glycine, Glycyrrhiza, Lens, Phaseolus, Pisum , Vicia and Vigna . The edible part is usually the seed or legume, or both. Species of these genera and many others, particularly in Anthyllis , Ceratonia, Coronilla, Galega, Lathyrus, Lotus , Lupinus, Medicago, Melilotus, Trifolium and Trigonella are cultivated for fodder on a large scale or are planted to improve pasture. Cultivated ornamental plants are to be found in the majority o f European genera. In addition to some of those mentioned above, 1 Edit. V. H. Heywood and P. W. Ball. the following are of particular importance in this respect: Acacia , Amorpha, Caragana, Cercis, Colutea, Cytisus and Genista and related genera, Laburnum , Robinia, Sophora, Spartium and Wisteria .

1 Stamens numerous, free, longer than the corolla 4. Acacia 1 Stamens not more than 10, the filaments often partly or completely united, usually shorter than the corolla

2

Corolla

absent

;

stamens

5, free

2. Ceratonia 2 Corolla

present

;

stamens

more

than 5 or the

filaments united

3 At least some leaves 2-pinnate; corolla scarcely zygomorphic

3. Gleditsia 3 Leaves simple, 3-foliolate or 1-pinnate; corolla strongly zygomorphic

4 Flowers with 1 petal 42. Amorpha 4 Flowers with 5 petals, 2 or more sometimes connate

5 Leaves consisting of a tendril only (but with large leaf-like stipules) 51. Lathyrus 5 Leaves not consisting of a tendril only

6 At least some leaves paripinnate, imparipinnate or digitate; leaflets 2, 4 or more

7 Leaves paripinnate; rhachis often ending in a spine or tendril

8 Shrubs orsmalltrees;rhachis oftenendingin aspine

9 Pedicels 5 mm or more, articulated 36. Caragana 9 Pedicelsusuallylessthan5 mm, notarticulated

10 Stipulesforming spines 35. Halimodendron 10 Stipules not forming spines 38. Astragalus 8 Herbs;rhachis not endingin aspine

11 Stipules adnate to the petiole; calyx bilabiate, the upper lip with 4 teeth, the lower with 1 tooth

74. Arachis 11 Stipules not adnate to the petiole; calyx actinomorphic or if bilabiate, the upper lip with 2 teeth,

the lower with 3 teeth

12 Stem and leaves glandular-pubescent 48. Cicer 12 Stem and leaves not glandular-pubescent

13 Stem winged 51. Lathyrus 13 Stem not winged

14 Leaflets parallel-veined 51. Lathyrus 14 Leaflets pinnately veined

15 Calyx-teeth all equal and at least twice as long as the tube 50. Lens 15 At least 2 calyx-teeth less than twice as long as the tube

16 Calyx-teeth ±leaf-like; stipules up to 10 cm

52. Pisum 16 Calyx-teeth not leaf-like; stipules not more than 2 cm

17 Style pubescent all round or on the lower side, or glabrous 49. Vicia 17 Style pubescent on the upper side only

51. Lathyrus 7 Leaves imparipinnateordigitate

18 Principallateralveinsoftheleafletsterminatingat the margin, often in a tooth

19 Glabrous or glabrescent, eglandular 57. Trifolium 19 Variously hairy and glandular, sometimes sparsely so

20 Calyx gibbous at base; stipules free from petiole

48. Cicer 20 Calyx not gibbous at base; stipules adnate to petiole

53. Ononis 18 Lateralveinsoftheleafletsanastomosingandnot reaching the margin

21 At least some flowers in terminal or apparently terminal inflorescences

22 Leaves digitate 28. Lupinus 22 Leaves imparipinnate

23 Climbing shrubs; flowers in pendent racemes;

legume velutinous 31. Wisteria 23 Not climbing; flowers in erect inflorescences;

legume not velutinous

24 Trees; flowers in large panicles 5. Sophora 24 Herbs or small shrubs; flowers in heads or racemes

25 Stamens free; flowers in racemes 5 cm or more

5. Sophora 25 Stamens connate; flowers in heads 63. Anthyllis 21 Allflowersaxillary orin axillary inflorescences

26 Plant glandular, at least in part

27 Racemes pendent; legume 5-10 cm 30. Robinia 27 Racemes erect; legume not more than 3 cm

28 Dwarf shrubs; corolla 20-25 mm 37. Calophaca 28 Herbs; corolla less than 20 mm 41. Glycyrrhiza 26 Plant eglandular

29 Flowers in umbels or clusters, the pedicels arising

± from the same point

30 Legume lomentaceous

31 Keel obtuse; legume strongly reticulate-veined

64. Ornithopus 31 Keel acute; legume not or only faintly reticulateveined

32 Segments of the legume lunate or horseshoeshaped to rectangular with a semicircular to orbicular sinus which has a curved protuberance at its base 66. Hippocrepis 32 Segments of the legume linear or oblong, straight or slightly curved

33 Stamens diadelphous; legume glabrous

65. Coronilla 33 Stamens monadelphous; legume pubescent

67. Hammatolobium 30 Legume dehiscent or indéhiscent, not lomentaceous

34 Keel beaked

35 Leaves with 4-7 pairs of leaflets 62. Securigera 35 Leaves with 2-3 pairs of leaflets or simple

36 Lower leaves simple; upper leaves with 2-3

pairs ofleaflets; legume spirally twisted and flattened so that it is circular in outline

61. Hymenocarpus 36 All leaves with 2 pairs of leaflets; legume linear or oblong, straight or curved 59. Lotus 34 Keel not beaked

37 Keel very dark red or black 58. Dorycnium 37 Keel not dark red or black

38 Leaves imparipinnate

39 Umbels without an involucre 38. Astragalus 39 Umbels with an involucre of scarious bracts

72. Ebenus 38 Leaves digitate or apparently so

40 Pedicels 15-20 mm; leaflets with a spinescent apex 36. Caragana 40 Pedicels not more than 5 mm; leaflets without a spinescent apex 27. Lotononis 29 Flowers in racemes or condensed panicles or solitary

41 Leafletsdistinctlyparallel-veined 51. Lathyrus 41 Leaflets pinnately veined or the lateral veins obscure

42 Leaflets with a spinescent apex 36. Caragana 42 Leaflets without a spinescent apex

43 Spiny shrubs 69. Eversmannia 43 Unarmed herbs, shrubs or trees

44 Legume lomentaceous

45 Racemes (2-)4- to many-flowered

70. Hedysarum 45 Flowers solitary, axillary

46 Corolla 4-7 mm; segments of the legume flat and rectangular with a suborbicular sinus 66. Hippocrepis 46 Corolla 10-14 mm; segments of the legume ovoid-oblong, terete 67. Hammatolobium 44 Legume not lomentaceous

47 Legume indéhiscent, usually toothed or spiny

48 Legume oblong, dorsiventrally compressed,

the valves sinuate-dentate on the back; corolla blue, or yellow with a blue apex

40. Biserrula 48 Legume ± orbicular, the margin usually toothed, the sides reticulate-veined or foveolate and the veins often toothed; corolla white, pink or purple

71. Onobrychis 47 Legume usually dehiscent, not toothed or spiny

49 Racemes 10 cm or more, pendent; stipules usually forming spines; leaflets stipellate

30. Robinia 49 Racemes usually less than 10 cm, erect; stipules not forming spines

50 Leaflets stipellate 44. Apios 50 Leaflets not stipellate

51 Legume strongly inflated, membranous

52 Shrubs up to 2 m or more 33. Colutea 52 Acaulescent herbs 38. Astragalus 51 Legume not or only slightly inflated, not membranous 53 Keel beaked 59. Lotus 53 Keel not beaked but sometimes mucronate

54 Keel mucronate at apex

55 Mucro on the adaxial side of the keel

38. Astragalus 55 Mucro on the abaxial side of the keel

39. Oxytropis 54 Keel not mucronate at apex

56 Stamens monadelphous

57 Rhachis very short so that the leaves are almost digitate; leaflets 1-2

pairs; corolla bright pink

72. Ehenus 57 Rhachis long; leaflets 4-10 pairs;

corolla yellow or white to bluishviolet

58 Corolla 10-15 mm; perennial

32. Galega

58 Corolla c. 3 mm; annual

38. Astragalus 56 Stamens diadelphous

59 Style glabrous 38. Astragalus 59 Style pubescent on the lower side

49. Vicia 6 Leaves simple, 1-foliolate or 3-foliolate, sometimes very small

60 Leaves 7-12cm, simple, suborbicular, cordate; adaxial petal innermost 1. Cercis 60 Leaves3 -foliolate,orsimple,butneversuborbicular and cordate; adaxial petal outermost

61 Principal lateral veinsoftheleafletsterminatingat the margin; leaflets often toothed

62 Plant glandular-pubescent, at least above

63 Stamens monadelphous; legume straight or very slightly curved 53. Ononis 63 Stamens diadelphous; legume falcate to spirally coiled, rarely almost straight 56. Medicago 62 Plant not glandular-pubescent

64 At least some petal-claws adnate to the staminal tube; corolla usually persistent in fruit

57. Trifolium 64 Petal-claws free from the staminal tube; corolla deciduous

65 Filaments of at least 5 stamens dilated at the apex

57. Trifolium 65 Filaments all filiform

66 Legume coiled in 1 or more turns of a spiral

56. Medicago 66 Legume straight or curved

67 Perennial

68 Legume obovate or ovate to subglobose

54. Melilotus 68 Legume oblong, oblong-falcate, oblong- reniform, reniform or variously curved

56. Medicago 67 Annual or biennial

69 Corolla blue 55. Trigonella 69 Corolla white or yellow

70 Legume linear or oblong, at least 3 times as long as wide 55. Trigonella 70 Legume ovate or obovate to subglobose or reniform, less than 3 times as long as wide

71 Legume reniform 56. Medicago 71 Legume ovate or obovate to subglobose

72 Legume without or with a very short beak and without a membranous wing

54. Melilotus 72 Legume with a long, curved beak or with a broad membranous wing on the margin

55. Trigonella 61 Principal lateral veins oftheleafletsanastomosingand not reaching the margin, sometimes obscure; leaflets not toothed (leaves sometimes caducous or reduced to a spine-tipped phyllode)

73 Plantspiny

74 Corolla pink, red, purple or violet-blue

75 Leaves c. 5 mm; calyx bilabiate 23. Erbacea 75 Leaves 10-20 mm; calyx actinomorphic 73. Alhagi 74 Corolla yellow

76 Leaves ofadult plantsreduced to persistentspine- tipped phyllodes

77 Leaves and branches mostly alternate; legume scarcely exserted from the calyx 24. Ulex 77 Leaves and branches mostly opposite; legume conspicuously exserted from the calyx

25. Stauracanthus 76 Leaves not spine-tipped, often caducous

78 Calyx tubular, with 5 short teeth,theupperpor­

tion breaking away atanthesisto leavea cuplike remnant 10. Calicotome 78 Upper part of calyx not breaking away at anthesis

79 Calyx with 5 ± equalteeth, notoronly slightly bilabiate 63. Anthyllis 79 Calyx ± distinctly bilabiate

80 Upper lip of calyx with 2 short teeth; leaves

3-foliolate 13. Chamaecytisus 80 Upper lip of calyx deeply 2-fid; leaves often

1-foliolate

81 Calyx not more than 7 mm 16. Genista 81 Calyx 7 mm or more

82 Leaves and branchesmostly alternate; calyx not inflated 16. Genista 82 Leavesand branchesmostly opposite; calyx somewhat inflated 18. Echinospartum 73 Plantnotspiny

83 Young stems broadly winged 17. Chamaespartium 83 Young stems not broadly winged

84 Leaflets stipellate; leaves 3-foliolate

85 Corolla notmore than 7 mm; plantwith reddishbrown hairs 47. Glycine 85 Corolla 10 mm or more; plantglabrousorwith whitish hairs

86 Beak of the keel forming1^—2 turns ofa spiral

45. Phaseolus 86 Beak of the keel recurved 46. Vigna 84 Leaflets not stipellate; leavessimple or3 -foliolate

87 Legume with prominent glandulartubercles

26. Adenocarpus 87 Legume without glandulartubercles(sometimes with glandular hairs)

88 Leaves simple or 1-foliolate, sometimes very small

89 Annual herbs

90 Leaves linear, grass-like; legume dehiscent

51. Lathyrus 90 Leaves obovate or elliptical, not grass-like;

legume indéhiscent 68. Scorpiurus 89 Shrubs or perennialherbs,woody atbase

91 Corolla violet; leaves 1-3 mm,scarious

34. Eremosparton 91 Corolla white or yellow; leavesusually larger,

herbaceous, sometimescaducous

92 Calyx caducous after anthesis 20. Lygos 92 Calyx not caducous

93 Calyx split to the base adaxially 21. Spartium 93 Calyx not splitto the base

94 Calyx ± tubular; legume ± included inthe persistentcalyx 63. Anthyllis 94 Calyx campanulate; legume exserted, or the calyx not persistent

95 Upper lip of calyx with short teeth

12. Cytisus

95 Upper lip ofcalyx deeply 2-fid ordeeply toothed

96 Legume ovoid, oblong or falcate, dehis­

cent, not inflated 16. Genista 96 Legume globose-inflated, not or tardily

dehiscent 20. Lygos 88 At least some leaves 3-foliolate

97 Leaflets conspicuously glandular-punctate

43. Psoralea 9'? Leaflets not or very minutely glandular- punctate

98 Legume lomentaceous

99 Annual; corolla 4-8 mm 65. Coronilla 99 Perennial; corolla 10-14 mm

67. Hammatolobium 98 Legume not lomentaceous

100 Calyx usually bilabiate, the upper lip with

4 teeth, the lower with 1 tooth, some­ what shorter than the upper 27. Lotononis 100 Calyx actinomorphic or bilabiate, but never

with the upper lip with 4 teeth and the lower with 1 tooth

101Annual or perennial herbs, sometimes

with a woody stock

102 Stamens free; flowers in clusters of 3

arranged in a terminal leafy raceme

6. Thermopsis 102 Stamens connate; flowers not in clusters

of 3 arranged in a terminal leafy

raceme

103 Calyx inflated, 4-5-6 mm wide in

flower, up to 12 mm wide in fruit

and enclosing the legume 63. Anthyllis 103 Calyx less than 4-5 mm wide, not

inflated

104 Keel very dark red or black

58. Dorycnium 104 Keel not very dark red or black

105 Stamens monadelphous; stipules

completely free from the petiole

29. Argyrolobium 105 Stamens diadelphous; stipules in­

serted on or adnate to the base of

the petiole

106 Stipules inserted at the base of the

petiole; legume not longitudinally

winged 59. Lotus 106 Stipules inserted on the stem, and

adnate to the base of the petiole;

legume with 2 or 4 longitudinal

wings 60. Tetragonolobus 101 Shrubs or trees

107 Stamens free; stipules connate, con­

spicuous 7. Anagyris 107 Stamens variously connate; stipules free,

often minute or absent

108 Legume ± included in the persistent

calyx; calyx with 5 ±equal teeth

109 Flowers solitary or in clusters of 2-3;

calyx-teeth shorter than tube;

corolla yellow 63. Anthyllis 109 Flowers in dense axillary racemes;

calyx-teeth longer than tube; corolla

bright pink 72. Ebenus 108 Legume exserted or the calyx deci­

duous; calyx bilabiate

110 Flowers in pendent racemes 8. Laburnum 110 Flowers in erect inflorescences

111 Legume broadly winged 9. Podocytisus 111 Legume not winged

112 Upper lip of calyx deeply 2-fid

113 Calyx-tube distinctly shorter than

lips 29. Argyrolobium

113 Calyx-tube as long as or longer

than lips

114 Petiole 15—50 mm; legume 35-

50 mm 22. Petteria

114 Petiole not more than 15mm;

legume not more than 25 mm

115 Standard 4-5-5 mm; calyx cam­

panulate 19. Gonocytisus

115 Standard 7-20 mm; calyx tubular-

campanulate

116 Pedicel 5-10 mm; legume glab­

rous 12. Cytisus

116 Pedicel 1-3 mm; legume hairy

117 Flowers in umbellate heads

16. Genista

117 Flowers axillary or in axillary

clusters

118 Standard distinctly shorter

than keel; seeds estrophio-

late 16. Genista

118 Standard longer than keel;

seeds strophiolate 15. Teline

112 Upper lip of calyx with 2 short teeth

119 Calyx tubular 13. Chamaecytisus

119 Calyx campanulate

120 Flowers axillary, arranged in

leafy racemes 12. Cytisus

120 Flowers in leafless, terminal heads

or racemes

121 Flowers in usually 2- or 4-

flowered heads 14. Chronanthus

121 Flowers in long racemes

122 Twigs hairy 11. Lembotropis

122 Twigs glabrous 12. Cytisus

Subfam. Caesalpinioideae

Flowers more or less zygomorphic. Sepals and petals imbricate; the adaxial petal innermost and so overlapped by the lateral petals. Stamens usually not more than 10, free (in European spp.).