1a. Plants with stellate hairs; prickles often present.
2a. Plants unarmed; leaves entire; anthers stout, not tapering; inflorescences many-flowered, flat or rounded
panicles held upright above foliage in flower and fruit ........................................................................................ 2. S. erianthum
2b. Plants mostly armed; leaves mostly dentate or lobed; anthers tapering distally; inflorescences unbranched or
1-branched, rarely more, angling from twigs, held below foliage or along stems.
3a. Calyx enlarged, closely enveloping most of berry.
4a. Corolla yellow; anthers more than 1 cm, unequal; berry completely enveloped by calyx at maturity; fruiting calyx with dense prickles 1–2 cm ........................................................................................................... 38. S. angustifolium
4b. Corolla white, blue, or purplish; anthers less than 1 cm, equal; berry partly or completely exposed from
enlarged calyx at maturity; fruiting calyx copiously or sparingly armed with prickles less than 1 cm.
5a. Leaves usually pinnate-parted, lobes pinnately lobed or dentate; stems pubescent with simple,
many-celled glandular hairs and few stellate hairs ....................................................................... 37. S. sisymbriifolium
5b. Leaves entire or irregularly dentate; stems with only stellate hairs.
6a. Inflorescences less than 5 cm, peduncle less than 5 mm; corolla white ............................................ 36. S. griffithii
6b. Inflorescences more than 5 cm, peduncle more than 5 mm; corolla blue or purple .................. 35. S. barbisetum
3b. Calyx hardly or not enlarged, not enveloping berry.
7a. Fruit densely stellate hirsute with persistent tomentum; plants tomentose; calyx lobes nearly leaflike, more than 8 mm ..................................................................................................................................................... 34. S. lasiocarpum
7b. Fruit glabrous; plants variously pubescent; calyx lobes not leaflike, mostly less than 7 mm.
8a. Corolla more than 5 cm wide, deep purple, fading white, with contrasting abaxial pleats; sturdy trees to 12 m tall; fruit more than 3 cm ........................................................................................................................... 26. S. wrightii
8b. Corolla less than 5 cm wide, white or purple, not conspicuously fading, lacking contrasting pleats;
shrubs, or if small trees then trunk slender; fruit mostly less than 3 cm.
9a. Inflorescences mostly 1–3-branched; plants mostly more than 1 m.
10a. Leaves 3–5-lobed or parted, with loose and softly lanate pubescence on both surfaces, drying of
1 color; plants overall with rust-colored, short- or long-stalked, bristly-hispid stellate hairs
....................................................................................................................................................... 20. S. chrysotrichum
10b. Leaves subentire or variously lobed, minutely scabrous with mostly sessile stellate pubescence
adaxially, drying of different colors; leaves and stems lacking bristly, long-stalked hairs.
11a. Corolla white; pedicel with simple glandular hairs mixed with stellate ones; fruit yellow, more than 1 cm in diam. ........................................................................................................................... 25. S. torvum
11b. Corolla blue, violet, or purple; pedicel with stellate hairs only; fruit red, less than 1 cm in
diam.
12a. Leaves subentire or 6- or 7-sinuate lobed, ovate-elliptic; corolla more than 8 mm
............................................................................................................................................. 22. S. macaonense