Hypericum sect. Hypericum

Synonyms: Hypericum sect. Concinna N. Robson Hypericum sect. Graveolentia N. Robson
Treatment appears in FNA Volume 6. Treatment on page 97. Mentioned on page 73.

Herbs, perennial, [subshrubs]; black glands usually on leaves, sepals, and petals and, sometimes, on stems and anthers. Leaves persistent or tardily deciduous, (base not articulated). Flowers 6–35 mm diam.; sepals persistent, 5; petals persistent, 5; stamens persistent, 20–109, in 5 fascicles, fascicles connate as 2 + 2 + 1; ovary 3(–4)-merous; placentation axile; styles spreading, bases distinct; stigmas relatively small. Seeds not or slightly carinate. Species 22 (8, including 1 hybrid, in the flora): North America, Mexico, West Indies, Central America, South America.

Distribution

North America, Mexico, West Indies, Central America, South America.

Discussion

Species 22 (8 in the flora).

Key

1 Herbs rarely with rooting base, bushy; leaf blades usually conduplicate; sepals markedly imbricate. Hypericum concinnum
1 Herbs usually with rooting base (except H. punctatum), not bushy; leaf blades not conduplicate; sepals not or scarcely imbricate. > 2
2 Stems with black glands in raised lines or without black glands; leaf blades: tertiary veins not densely reticulate, black glands intramarginal, (± dense to spaced), and laminar, (relatively few and distal or absent); capsules ovoid, broadly ovoid, narrowly ovoid-pyramidal, or oblanceoloid > 3
2 Stems with black glands scattered on or near lines or all over; leaf blades: tertiary veins densely reticulate toward margins, black glands intramarginal (dense) and laminar (scattered); capsules ellipsoid, ovoid, broadly ovoid, or subglobose > 5
3 Stems from rooting, creeping base, internodes weakly 2-lined or not lined, without black glands, rarely with reddish glands; petals sometimes red-tinged. Hypericum scouleri
3 Stems from rooting, not creeping, base, internodes 2- or 4-lined, with black glands in lines; petals not red-tinged > 4
4 Stems: internodes (at least some) 4-lined; sepals broadly ovate to oblong, apex rounded-apiculate to erose-denticulate; capsules with longitudinal vittae (narrow linear glands). Hypericum maculatum
4 Stems: internodes 2-lined; sepals lanceolate or narrowly oblong to linear, apex acute to aristate; capsules with longitudinal vittae and shorter, oblique vittae. Hypericum perforatum
5 Leaf blade apex usually acute, rarely obtuse to rounded; inflorescence subsidiary branches ascending to widely spreading; anther gland amber or pellucid. Hypericum pseudomaculatum
5 Leaf blade apex usually obtuse, rounded, retuse, or subretuse, rarely acute; inflorescence subsidiary branches narrowly ascending or curved-ascending; anther gland black > 6
6 Inflorescences (2–)5–14(–22)-flowered; petals 11–18 mm; styles 5.6–12 mm. Hypericum graveolens
6 Inflorescences (5–)13–600-flowered; petals 3–11 mm; styles 1–5 mm > 7
7 Stems with black glands on or near lines or all over; flowers 15–20 mm diam.; capsules with longitudinal vittae. Hypericum ×mitchellianum
7 Stems with black glands scattered; flowers 8–15 mm diam.; capsules with longitudinal vittae or elongate to ovoid vesicles. Hypericum punctatum