1	Capsule margins on abaxial locule not winged, adaxial locule longer and winged (sometimes not or obscurely winged in P. watsonii); seed coats with rows of pits (0.05 mm diam.); flowers white; racemes loosely flowered, cylindric or subcapitate; Arizona, New Mexico, Texas.		(2)
2 (1)	Stems glabrous (rarely with a few scattered hairs)		12 Polygala hemipterocarpa
3	Wing sepals (2.4–)2.7–4.5 mm; racemes cylindric (flowering portion may appear subcapitate from deciduous fruit), (1–)1.5–7.8 × 0.4–0.8 cm		25 Polygala scoparioides
+	Wing sepals (3.5–)4–6 mm; racemes subcapitate, 0.5–1.4(–2.5) × 1 cm		31 Polygala watsonii
4	Pedicels winged; flowers usually yellow, orange, green, or greenish, rarely white; racemes in cymose panicles or capitate.		(5)
+	Pedicels not winged; flowers white, cream, green or greenish, pink, purple, reddish purple, or blue, not bright yellow or orange; racemes solitary (not in cymose panicles), sometimes spikelike or nearly so, cylindric, cylindric-conic, or capitate.		(11)
5 (4)	Racemes in cymose panicles, ± flat-topped; basal leaf blades obovate, spatulate, narrowly elliptic, linear-lanceolate, or linear, sometimes withered or nearly so at anthesis.		(6)
+	Racemes solitary (not in panicles), capitate; basal leaf blades usually obovate, oblanceolate, linear-oblanceolate, or spatulate, rarely elliptic, often persistent.		(8)
6 (5)	Corollas pale yellowish apically, wing sepals white, cream, or, sometimes, greenish tinged; pedicels 0.6–1.2 mm		3 Polygala balduinii
+	Corollas and wing sepals bright yellow; pedicels (1–)1.3–4 mm.		(7)
7 (6)	Basal leaf blades linear-lanceolate to linear, forming large, persistent rosette; biennials, 4–12 dm		10 Polygala cymosa
+	Basal leaf blades obovate or spatulate to narrowly elliptic, usually absent at anthesis; annuals or biennials, 1.5–4(–5) dm		22 Polygala ramosa
8 (5)	Flowers bright yellow to orange, drying pale yellow to dark greenish brown.		(9)
+	Flowers lemon yellow, greenish yellow, or green, sometimes drying green or yellowish green.		(10)
9 (8)	Flowers bright orange, usually drying pale yellow; racemes (0.8–)1.2–2 cm diam.		17 Polygala lutea
+	Flowers bright yellow, drying pale yellow to dark greenish brown; racemes 1.8–2.5 cm diam.		23 Polygala rugelii
10 (8)	Flowers lemon yellow to greenish yellow; wing sepals elliptic to oblong- lanceolate, tips 0.7–1.6 mm, apices involute; seeds 0.8–1.8 mm		19 Polygala nana
+	Flowers green or greenish yellow; wing sepals usually lanceolate, sometimes oblong-lanceolate, tips 0.5–0.9 mm, apices usually flat to slightly involute; seeds 1.9–2.3 mm		28 Polygala smallii
11 (4)	Seed hairs glochidiate; leaves whorled (at least proximally); Arizona		11 Polygala glochidata
+	Seed hairs not glochidiate; leaves usually whorled or alternate, rarely opposite or subopposite; widespread.		(12)
12 (11)	Leaves whorled, at least at proximalmost 1 or 2 nodes.		(13)
+	Leaves mostly alternate, proximal leaves sometimes opposite or whorled (in P. incarnata, P. lewtonii, and P. polygama).		(19)
13 (12)	Perennials, multi-stemmed, with thickened caudices; flowers white or greenish white.		(14)
+	Annuals, single-stemmed (usually branched distally), with slender taproots or fibrous roots; flowers mostly pink or purple, sometimes white, greenish, or greenish white.		(15)
14 (13)	Capsules ovoid, ellipsoid, or oblong, 1.3–1.6 mm diam.; w North America		1 Polygala alba
+	Capsules subglobose to broadly ellipsoid, (1.2–)2–3 mm diam.; se United States		4 Polygala boykinii
15 (13)	Racemes spikelike or nearly so, cylindric, cylindric-conic, or conic; bracts deciduous; pedicels 0–1(–2) mm.		(16)
+	Racemes mostly capitate or apically rounded, sometimes cylindric; bracts persistent; pedicels (0.7–)1–2.4 mm.		(17)
16 (15)	Seeds glabrous		15 Polygala leptostachys
+	Seeds pubescent		29 Polygala verticillata (in part)
17 (15)	Wing sepals ovate to deltate, apices acuminate, often strongly cuspidate		8 Polygala cruciata
+	Wing sepals ovate to ovate-oblong or ovate-oblanceolate, apices acute, short-mucronate.		(18)
18 (17)	Wing sepals 1.5–2.5 mm wide; leaf blades 1–4(–7) mm wide		5 Polygala brevifolia
+	Wing sepals 1.3–2 mm wide; leaf blades 0.5–1 mm wide		13 Polygala hookeri
19 (12)	Cleistogamous flowers present, usually below, rarely just above, soil surface, sometimes in proximal leaf axils later in season; racemes loosely cylindric; short-lived perennials, biennials, or annuals, usually multi-stemmed, sometimes single-stemmed.		(20)
+	Cleistogamous flowers absent; racemes sometimes spikelike or nearly so, often densely capitate or cylindric, sometimes cylindric-conic; mostly annuals, single-stemmed, sometimes perennials and single- or multi-stemmed.		(22)
20 (19)	Capsule margins winged		7 Polygala crenata
+	Capsule margins not winged.		(21)
21 (20)	Capsules ellipsoid or oblong, 2.5–3.5 × 1–1.5 mm, length 2–3 times width; flowers 6–8 mm; non-wing sepals 0.8–1.1 mm		16 Polygala lewtonii
+	Capsules ellipsoid or globose-ovoid, 2–4 × 2–3 mm, length less than 2 times width; flowers 4–6 mm; non-wing sepals 1.3–2.5 mm		21 Polygala polygama
22 (19)	Leaf blades (1.5–)8–35 mm wide, margins often appearing serrulate (toothlike projections associated with marginal cilia		26 Polygala senega
+	Leaf blades 0.3–2(–5.5) mm wide (rarely more than 4 mm); margins entire.		(23)
23 (22)	Capsule margins narrowly winged; short-lived perennials, usually multi-stemmed (rarely 1 or few-stemmed) from small caudices; British Columbia, Michigan, Oregon		30 Polygala vulgaris
+	Capsule margins not winged; annuals (sometimes perennial in P. setacea), single-stemmed, from taproots; s, e North America.		(24)
24 (23)	Wing sepals less than 1/2 as long as keel petals; stems glaucous; arils scarcely lobed		14 Polygala incarnata
+	Wing sepals usually (sub)equaling or exceeding keel petals, rarely slightly shorter; stems not or seldom glaucous; arils usually lobed, rarely vestigial.		(25)
25 (24)	Leaf blades subulate scales, 0.5–1.6(–2) mm		27 Polygala setacea
+	Leaf blades linear, linear-oblong, spatulate, oblanceolate, elliptic, linear-subulate, or subfiliform, 3–25(–40) mm.		(26)
26 (25)	Wing sepals 1.5–2 times longer than keel petals; aril lobes (1/2–)2/3–nearly as long as seed		24 Polygala sanguinea
+	Wing sepals equaling or slightly longer than keel petals (shorter in P. chapmanii, sometimes slightly shorter in P. mariana and P. nuttallii); aril lobes to 1/8–1/2 length of seed or vestigial.		(27)
27 (26)	Bracts persistent (P. chapmanii often also with scattered deciduous ones).		(28)
+	Bracts deciduous (rarely a few persistent and scattered).		(30)
28 (27)	Racemes 0.4–0.7 cm diam.; wing sepals 2–3 mm; pedicels 0.5(–1) mm		20 Polygala nuttallii
+	Racemes 0.6–1.3 cm diam.; wing sepals 2.5–5 mm; pedicels 0.7–2.8 mm.		(29)
29 (28)	Wing sepals 2.5–3.3(–3.8) mm; capsules 1.5–2.3 mm		6 Polygala chapmanii
+	Wing sepals 3–5 mm; capsules (1.7–)2.5–3 mm		9 Polygala curtissii
30 (27)	Flowers white		29 Polygala verticillata (in part)
+	Flowers usually pink or purple, rarely white.		(31)
31 (30)	Racemes cylindric, 1.5–13 × 0.5–0.6 cm; flowers 1.6–2.2 mm; pedicels 0.8–1 mm		2 Polygala appendiculata
+	Racemes capitate, (0.5–)1–3.5 × 0.6–1.1 cm; flowers 4–5.7 mm; pedicels 1.5–3.5 mm		18 Polygala mariana