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1 Leaflets denticulate (sometimes inconspicuously so); [tribe Trifolieae]. |
..2 Inflorescences elongate racemes with an axis 5-15 cm long, the flowers well-spaced along the axis, the overall inflorescence much longer than its diameter |
..2 Inflorescences umbellate or headlike clusters or short racemes with an axis < 2 cm long, the flowers closely clustered, the overall inflorescence little (if at all) longer than its diameter. |
....3 Legumes spirally coiled or curved, often tuberculate or prickly; stems 4-angled towards the tip |
....3 Legumes straight or nearly so, never tuberculate or prickly; stems terete or flattened (2-angled) towards the tip |
1 Leaflets entire (and sometimes also with 1 or 2 broad lobes), or with scattered, irregular large teeth ( Pachyrhizus erosus). |
......4 Main stems erect or ascending, not trailing, twining, or otherwise vine-like. |
........5 Flowers not papilionaceous (the wings and keel epistemonous, arising terminally or laterally from the stamen tube), barely bilaterally symmetrical; stamens 5, monadelphous; [tribe Amorpheae] |
........5 Flowers papilionaceous; stamens 10, diadelphous or monadelphous. |
..........6 Plants with separate leafy and flowering stems (the flowering stems naked or nearly so of leaves). |
............ 7 Standard bright red, remaining folded, 30-50 mm long; leaves hastately lobed; fruit a torulose legume, 6-20 cm long, the seeds red; [tribe Phaseoleae] |
............ 7 Standard white or pink, expanded, 4-8 mm long; leaves not hastate; fruit a flattened loment, < 5 cm long, the seeds drab; [tribe Desmodieae] |
..........6 Plants bearing leaves and flowers on the same stems. |
............ ..8 Leaves, stems, and/or calyces glandular-punctate. |
............ ....9 Corollas pink or lavender/purplish; leaflets estipellate; fruit 1-seeded, indeciscent; [tribe Psoraleae] |
............ ....9 Corollas yellow; leaflets stipellate; fruit 2-many-seeded, dehiscent; [tribe Phaseoleae, subtribe Cajaninae] |
............ ..8 Leaves, stems, and calyces lacking punctate glands. |
............ ......10 Leaflet blades large, at least the largest terminal leaflets on a plant > 5 cm long. |
............ ........11 Stipels absent on the petiolules of mature leaflets; stamens monadelphous. |
............ ..........12 Fruit a legume (not segmented into 1-seed dispersal units), hairy but the hairs not hooked; [plants cultivated as garden plants, rare as waifs] |
............ ..........12 Fruit a loment (separating into single-seeded segments), uncinulate (with hooked hairs, the fruits attaching to hairs or clothes as 'stick-tights'); [plants widespread, common] |
............ ........11 Stipels present, persistent; stamens diadelphous (9 and 1). |
............ ............ 13 Fruit a loment (separating into single-seeded segments), uncinulate (with hooked hairs, the fruits attaching to hairs or clothes as 'stick-tights'); [plants widespread, common] |
............ ............ 13 Fruit a legume (not segmented into 1-seed dispersal units), hairy but the hairs not hooked; [plants cultivated as crops or garden plants, rare as waifs] |
............ ............ ..14 Keel of corolla coiled 1-3 turns; stipules inconspicuous; [soy beans] |
............ ............ ..14 Keel of corolla not coiled; stipules conspicuous, persistent, striate; [bush green beans or lima beans] |
............ ......10 Leaflet blades smaller, all on a plant < 5 cm long. |
............ ............ ....15 Stipels present, persistent. |
............ ............ ......16 Fruit a loment (separating into single-seeded segments), uncinulate (with hooked hairs, the fruits attaching to hairs or clothes as 'stick-tights') |
............ ............ ......16 Fruit a several- to many-seeded legume, glabrous to hairy (but not uncinulate) |
............ ............ ....15 Stipels absent on the petiolules of mature leaflets. |
............ ............ ........17 Fruits dehiscent, a legume with 2 or more seeds. |
............ ............ ..........18 Terminal leaflet very similar in size as the 2 lateral leaflets; banner petal prominently striate-veined |
............ ............ ..........18 Terminal leaflet 2× or more as long as the 2 lateral leaflets; banner petal evenly colored |
............ ............ ........17 Fruits indehiscent: either 1-seeded, or a loment with 2 or more one-seeded (indehiscent) segments. |
............ ............ ............ 19 Petioles fused most of length with amplexicaul stipules, the leaves thus appearing sessile or nearly so; corollas lemon to orangy yellow; flowers subsessile; fruit a loment of 2 segments, the terminal segment fertile, the lower segment either sterile or fertile |
............ ............ ............ 19 Petioles free from stipules, leaves evidently petiolate; corollas white to pink; flowers pedicellate; fruit either 1-seeded, or a loment normally with 3+ segments |
............ ............ ............ ..20 Fruit a loment, with 1-3 segments; terminal leaflets 3-10 cm long, 1-1.5× as long as wide; stamens monadelphous |
............ ............ ............ ..20 Fruit 1-seeded; terminal leaflets 1-5 cm long, 1.2-8× as long as wide; stamens diadelphous (9 and 1) |
......4 Main stems trailing, twining, creeping, or climbing or sprawling over other vegetation. |
............ ............ ............ ....21 Leaves, stems, and/or calyces glandular-punctate; corollas yellow. |
............ ............ ............ ....21 Leaves, stems, and calyces lacking punctate glands; corollas yellow, pink, purplish, white, red, blue. |
............ ............ ............ ......22 Leaflet blades smaller, all on a plant < 5 cm long. |
............ ............ ............ ........23 Stipels absent on the petiolules of mature leaflets. |
............ ............ ............ ..........24 Fruit a loment of 2 segments, the terminal segment fertile, the lower segment either sterile or fertile; corollas lemon to orangy yellow |
............ ............ ............ ..........24 Fruit 1-seeded; corollas pink-purplish to white, or bronze to brick-red. |
............ ............ ............ ............ 25 Corollas pink-purplish to white |
............ ............ ............ ............ 25 Corollas bronze to brick-red |
............ ............ ............ ........23 Stipels present, persistent (minute in Amphicarpaea). |
............ ............ ............ ............ ..26 Fruit a loment (separating into single-seeded segments), uncinulate (with hooked hairs, the fruits attaching to hairs or clothes as 'stick-tights'). |
............ ............ ............ ............ ....27 Flowers in axillary or terminal racemes; leaflets rotund, broadly ovate, broadly elliptic, or narrowly elliptic, the larger > 1 cm long. |
............ ............ ............ ............ ....27 Flowers in axillary clusters; leaflets broadly obovate, 0.5-1 cm long |
............ ............ ............ ............ ..26 Fruit a legume, dehiscent (at least tardily), unsegmented, and with 2+ seeds. |
............ ............ ............ ............ ......28 Flowers resupinate (the pedicel twisted 180 degrees), the banner 2.5-5.5 cm long and positioned lowermost. |
............ ............ ............ ............ ........29 Calyx lobes equal to or longer than the calyx tube; fruits 3-5 mm wide |
............ ............ ............ ............ ........29 Calyx lobes shorter than the calyx tube; fruits 5-8 mm wide |
............ ............ ............ ............ ......28 Flowers not resupinate, the banner 0.7-2.5 cm long and positioned uppermost. |
............ ............ ............ ............ ..........30 Stipules caducous |
............ ............ ............ ............ ..........30 Stipules persistent, sometimes conspicuous, sometimes striate. |
............ ............ ............ ............ ............ 31 Keel petal and the included style straight to gently upcurved; stems very slender, < 0.75 mm in diameter |
............ ............ ............ ............ ............ 31 Keel petal and the included style either strongly curved upwards 90-180 degrees, or even more extensively coiled (asymmetrically and spirally) in towards the flower center; stems slender to thicker, > 0.75 mm in diameter. |
............ ............ ............ ............ ............ ..32 Keel petal and the included style strongly curved upwards 90-180 degrees; corollas yellow or pink to lavender (or whitish). |
............ ............ ............ ............ ............ ....33 Corollas pink to lavender (or whitish); corolla keel usually somewhat twisted, asymmetrical; [widespread in our region] |
............ ............ ............ ............ ............ ....33 Corollas yellow; corolla keel symmetrical; [mainly outer Coastal Plain] |
............ ............ ............ ............ ............ ..32 Keel petal and the included style extensively coiled > 180 degrees (asymmetrically and spirally) in towards the flower center; corollas pink, purple, maroon, purple-black (or whitish). |
............ ............ ............ ............ ............ ......34 Peduncles long, the flowers borne in clusters on a raceme axis shorter than the peduncle; plants glabrate to villous, the hairs not hooked |
............ ............ ............ ............ ............ ......34 Peduncles short, the flowers scattered along a (sometimes branched) raceme axis, the raceme axis about as long as or longer than the peduncle; plants uncinulate pubescent (use 20× magnification, or touch the plant for the 'tacky' feel) |
............ ............ ............ ......22 Leaflet blades large, at least the largest terminal leaflets on a plant > 5 cm long. |
............ ............ ............ ............ ............ ........35 Stipels absent on the petiolules of mature leaflets; stamens monadelphous |
............ ............ ............ ............ ............ ........35 Stipels present, persistent (minute in Amphicarpaea); stamens diadelphous (9 and 1) or monadelphous ( Pueraria). |
............ ............ ............ ............ ............ ..........36 Stamens monadelphous; robust herbaceous vine with stems to 30 m long; flowers purple, when fresh smelling like artificial grape flavoring. |
............ ............ ............ ............ ............ ..........36 Stamens diadelphous (9 and 1); herbacous vines with stems usually < 5 m long; flowers various in color, not 'grapy' in odor. |
............ ............ ............ ............ ............ ............ 37 Flowers resupinate (the pedicel twisted 180 degrees), the banner (standard) petal lowermost; banner (standard) 25-50 mm long, much larger than the other petals. |
............ ............ ............ ............ ............ ............ ..38 Calyx lobes equal to or longer than the calyx tube; fruits 3-5 mm wide |
............ ............ ............ ............ ............ ............ ..38 Calyx lobes shorter than the calyx tube; fruits 5-8 mm wide |
............ ............ ............ ............ ............ ............ 37 Flowers not resupinate, the banner (standard) uppermost; banner (standard) < 25 mm long, or if up to 30 mm then not much llonger than the other petals. |
............ ............ ............ ............ ............ ............ ....39 Fruit a loment (separating into single-seeded segments), uncinulate (with hooked hairs, the fruits attaching to hairs or clothes as 'stick-tights') |
............ ............ ............ ............ ............ ............ ....39 Fruit a several- to many-seeded legume, glabrous to hairy (but not uncinulate). |
............ ............ ............ ............ ............ ............ ......40 Keel incurved < 90 (-120) degrees; style glabrous or pubescent. |
............ ............ ............ ............ ............ ............ ........41 Stipules inconspicuous or obsolescent. |
............ ............ ............ ............ ............ ............ ..........42 Leaflets coarsely toothed; roots tuberous |
............ ............ ............ ............ ............ ............ ..........42 Leaflets with entire margins (sometimes with 1-2 rounded lobes); roots slender |
............ ............ ............ ............ ............ ............ ............ 43 Corolla 3-4 cm long; fruits constricted between the seeds; fruits with stinging hairs |
............ ............ ............ ............ ............ ............ ............ 43 Corolla < 2 cm long; fruits constricted or not; fruits glabrous or hairy, the hairs not stinging. |
............ ............ ............ ............ ............ ............ ............ ..44 Bracteoles below the calyx persistent; ventral suture of the fruit bumpy-nodose; style bearded |
............ ............ ............ ............ ............ ............ ............ ..44 Bracteoles caducous; ventral suture of the fruit not bumpy-nodose; style glabrous. |
............ ............ ............ ............ ............ ............ ............ ....45 Leaflets (2-) 4-8 cm long, 0.8-1.5 cm wide, 5-6× as long as wide; leaflet apices acute to obtuse; fruits not flanged or winged |
............ ............ ............ ............ ............ ............ ............ ....45 Leaflets 6-14 cm long, 4-10 cm wide, 1-1.3× as long as wide; leaflet apices strongly acuminate; fruits with a flange or wing along the ventral suture |
............ ............ ............ ............ ............ ............ ........41 Stipules persistent and conspicuous. |
............ ............ ............ ............ ............ ............ ............ ......46 Legume quadrangular in ×-section, 4-winged |
............ ............ ............ ............ ............ ............ ............ ......46 Legume circular, elliptic, or oblong in ×-section, not winged. |
............ ............ ............ ............ ............ ............ ............ ........47 Flowers clustered 3 or more at the inflorescence nodes; upper calyx lobes fused. |
............ ............ ............ ............ ............ ............ ............ ........47 Flowers arrayed differently; upper calyx lobes separate. |
............ ............ ............ ............ ............ ............ ............ ..........48 Keel petal and the included style straight to gently upcurved; stems very slender, < 0.75 mm in diameter |
............ ............ ............ ............ ............ ............ ............ ..........48 Keel petal and the included style strongly curved upwards 90-180 degrees; stems slender to thicker, > 0.75 mm in diameter |
............ ............ ............ ............ ............ ............ ......40 Keel petal and the included style either strongly curved upwards 90-180 degrees, or even more extensively coiled (asymmetrically and spirally) in towards the flower center; style or stigma pubescent. |
............ ............ ............ ............ ............ ............ ............ ............ 49 Plants uncinulate pubescent (use 20× magnification, or touch the plant for the 'tacky' feel) |
............ ............ ............ ............ ............ ............ ............ ............ 49 Plants glabrate to villous, the hairs not hooked. |
............ ............ ............ ............ ............ ............ ............ ............ ..50 Keel petal and the included style strongly curved upwards 90-180 degrees |
............ ............ ............ ............ ............ ............ ............ ............ ....51 Corolla keel symmetrical; [mainly outer Coastal Plain] |
............ ............ ............ ............ ............ ............ ............ ............ ....51 Corolla keel usually somewhat twisted, asymmetrical; [widespread in our region] |
............ ............ ............ ............ ............ ............ ............ ............ ..50 Keel petal and the included style even more extensively coiled (asymmetrically and spirally) in towards the flower center. |
............ ............ ............ ............ ............ ............ ............ ............ ......52 Corolla 2.5-4 cm long, the wings about as long as the other petals; leaflets not lobed |
............ ............ ............ ............ ............ ............ ............ ............ ......52 Corolla 1.5-2 cm long, the wing petals longer than the other petals; leaflets lobed |