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1 Leaves pinnately 3-foliolate; plant a prostrate or ascending vine; corolla orange, red, or bronze; [w. AR and w. LA westward]; [subgenus Leucocraspedon] |
1 Leaves palmately (1-) 3-7-foliolate; plant a caulescent or acaulescent herb; corolla blue, lavender, or purple to cream or white; [collectively widespread]. |
..2 Plants acaulescent or nearly so, the aboveground stem 0-2 cm long; leaves (3-) 5-7-foliolate; corollas 11-18 mm long. |
....3 Upper calyx lobes ca. 1 mm long, much shorter than the calyx tube; leaflets 5-7; [calcareous glades of the Interior (nw. GA, TN, n. AL)] |
....3 Upper calyx lobes 5-8 mm long, longer than or about the same length as the calyx tube; leaflets (3-) 5; [sw. AR and w. LA westward]. |
......4 Peduncles 1.0-3.5 cm long, < 1/2 as long as the subtending petiole; [wc. OK and nc. TX westwards and northwestwards] |
......4 Peduncles (1.7-) 4-14 cm long, > 1/2 as long as the subtending petiole. |
........5 Peduncles and petioles appressed-pubescent; leaflets 2.5-6.0× as long as wide, mostly less than 10 mm wide; [Edwards Plateau and western edge of the TX Coastal Plain] |
........5 Peduncles and petioles spreading pilose; leaflets 1.7-3.0× as long as wide, mostly 10-30 mm wide; [sw. AR and w. LA west through e. OK and e. TX] |
..2 Plants caulescent, 3-10 dm tall; leaves (1-) 3-7-foliolate; corollas 5-25 mm long. |
..........6 Flowering calyx 1.5-2.5 mm long, the legume (ca. 8 mm long) obviously exserted out of it at maturity; corolla 5-7 mm long; [IN, KY, and MS westward]; [former genus Psoralidium] |
..........6 Flowering calyx 7-10 mm long, the legume mostly included within it even at maturity (only the beak sometimes projecting); corolla 7-25 mm long. |
............ 7 Leaflets > (8-) 10× as long as wide; [OK and TX westward]. |
............ ..8 Corollas 12-18 mm long; calyx 8-10 mm (when in flower), enlarging to as much as 15 mm in fruit |
............ ..8 Corollas 9-11 mm long; calyx 4.5-5.5 mm long (when in flower), only slightly enlarging in fruit |
............ 7 Leaflets 1-8× as long as wide; [collectively widespread]. |
............ ....9 Leaves (1-) 3 (-4)-foliolate, the largest leaves on a plant 3 (-4)-foliolate; petioles of midstem leaves < 1 cm long; plants repeatedly and divaricately branched, “bushy”. |
............ ......10 Leaflets 1.0-1.8× as long as wide; petiolules 5-9 mm long; calyx ca. 7 mm long (when in flower), elongating to ca. 10 mm (in fruit); [se. VA south to c. peninsular FL, west to AL] |
............ ......10 Leaflets 2.0-4.0× as long as wide; petiolules 1.5-3 mm long; calyx 11-16 mm long; [SC and GA ( P. piedmontanum) or OK and TX ( P. reverchonii)]. |
............ ........11 Inflorescence nodes (4-) 6-13 (-15), each with (1-) 3 (-4) flowers; [lower Piedmont of SC and GA] |
............ ........11 Inflorescence nodes 2-3, each with 1-3 flowers; [Cross Timbers and Prairies region of sc. OK and nc. TX] |
............ ....9 Leaves 3-7-foliolate, at least the larger leaves on a plant 5- or 7-foliolate; petioles of midstem leaves (0.2-) 2-8 cm long; plants either repeatedly and divaricately branched, or less branched or unbranched. |
............ ..........12 Inflorescences with 2-7 flower clusters well spaced from one another; plant divaricately branched, bushy; corollas 7-11 mm long; leaflets 2-8× as long as wide |
............ ............ 13 Leaflets 2-4.5× as long as wide; herbs silvery sericeous; pedicels 0.5-1 mm long; [nc. OK westwards] |
............ ............ 13 Leaflets 4-8× as long as wide; herbs strigose or appressed canescent to glabrate, not silvery; pedicels 1-3 mm long; sw. AR, nw. LA, e. and nc. TX, and c. OK, westwards] |
............ ..........12 Inflorescences not interrupted; plant strict (unbranched) or moderately branched; corollas 14-25 mm long; leaflets 2-5 (-6)× as long as wide. |
............ ............ ..14 Plants eglandular (lacking sessile glands on stems, foliage, etc.); stems 0.3-5 dm tall; [e. OK, n. AR, and s. MO northward and westward] |
............ ............ ..14 Plants glandular; [e. OK and e. TX westward]. |
............ ............ ....15 Larger stipules < 2.5 mm wide |
............ ............ ....15 Larger stipules 2.5-7 mm wide. |
............ ............ ......16 Stem hairs appressed |
............ ............ ......16 Stem hairs spreading |