Flora of North America species comparison

terete, herbaceous at base, not from subterranean, branched caudex, proximal stems 1 mm diam.

alternate, odd-pinnate, pulvinate;

stipules present, persistent, sessile, divergent from stem, striate, triangular-ovate, not produced proximal to point of insertion; long-petiolate, petiole and rachis canaliculate, pubescent;

leaflets 3, stipels persistent, striate, often curved, linear, blades 1.3–5.6(–7.2) cm, membranous to papery, margins entire or lobed, sometimes basally lobed, surfaces sericeous or strigose.

leaflet blades lanceolate, margins usually entire, rarely shallowly lobed, sinus 0–1 mm, lateral leaflets 1.5–5.6 × 0.2–2.1 cm, terminal leaflet 1.7–5.4 × 0.2–2.3 cm, surfaces sericeous.

1–12(–22)-flowered, axillary, pseudoracemes, rachis much contracted, with 1–6(–11)-flowering nodes, nodes often swollen, glandular, each bearing at most 2 flowers;

primary bracts early deciduous or absent;

secondary bracts subtending pedicels, persistent, ovate to lanceolate;

bracteoles persistent, rigid and striate, lanceolate, equal to or longer than calyx tube.

with 1 or 2(–4) flower-bearing nodes.

angular.

slender, herbaceous, 1.2–11(–12.3) cm, 0.2–0.7 mm diam.

mostly shorter than calyx tube, thickened in fruit.

papilionaceous;

calyx campanulate, 1.3–7 mm, lobes 4 (due to connation of 2 adaxial lobes into 1 acute-attenuate lobe), abaxial lobe more narrowly triangular and often longest, lateral lobes triangular, adaxial lobes connate into acute lobe;

corolla pink or pinkish, banner often with yellowish maculae, keel pinkish, tip (beak) dark purple, 3.6–15 mm;

wings oblong, not projected beyond distal bend of keel;

keel petals connate along upper margin, incurved, with a prominent gibbosity along upper margin proximal to beak;

stamens 10, diadelphous;

anthers sub-basifixed, uniform;

pollen tricolporate;

ovary sessile, arched, sparsely to densely strigose, at base surrounded by a nectariferous sheath;

style incurved like the keel, often becoming twisted, jointed at the first (proximal) curve, distinctly incrassate and flattened, distal portion introrsely bearded;

stigma terminal and introrse.

bracteoles 0.8–2.3 mm, ± equal to calyx tube;

calyx tube 0.8–2.4 mm, lobes 0.5–1.5 mm;

banner light pink, 3.6–7(–8.3) mm;

wings light pink, 3.5–6.5 mm;

keel 3.5–6 mm, beak slightly curved, to 1 mm diam., mostly concealed by wings.

legumes, sessile, held horizontally or somewhat drooping, linear or slightly curved, cylindric to subcylindric, dehiscent with twisting valves, sericeous, strigose, glabrate, or glabrous.

subcylindric, laterally compressed, 1.2–4.7 × 0.2–0.4(–0.5) cm, usually sericeous.

4–10, spherical or oblong, subquadrate or reniform, ends truncate, usually covered with a cellular layer;

hilum oblanceolate, elongated 1/2 length of seed, rim-aril and hilar tongue much reduced, lens distinct and divided;

seedlings with epigeal germination.

4–9, distinctly mottled, reniform to oblong, without cellular or waxy covering.

, annual or perennial, unarmed, to 2 m. Stems slender, flexible, trailing or climbing, often branching at proximal nodes, not woody, sometimes lignescent at base, sparsely to densely short-pilose.

usually annual, rarely short-lived perennial, with relatively long, slender taproot.

= 11.