Herbs, annual or perennial (stems and leaves glabrous except 43. H. setosum); black glands absent. Leaves deciduous (base articulated) or persistent (base not articulated). Flowers 3–15 mm diam.; sepals persistent, (4–)5; petals persistent, (4–)5; stamens persistent, (5–)10–80, usually in continuous or interrupted ring, sometimes in 5 barely discernable fascicles, each of 1–2 stamens; ovary (2–)3(–4)-merous; placentation parietal; styles ± spreading, bases distinct; stigmas capitate or clavate. Seeds not carinate.

Distribution

North America, Mexico, West Indies, Central America, South America, Africa, Asia, Pacific Islands (New Zealand), Australia.

Discussion

Species 148 (16 in the flora).

Selected References

Webb, D. H. 1980. A Biosystematic Study of Hypericum Section Spachium in Eastern North America. Ph.D. dissertation. University of Tennessee.

Lower Taxa

Hypericum anagalloides, Hypericum boreale, Hypericum canadense, Hypericum cumulicola, Hypericum denticulatum, Hypericum drummondii, Hypericum erythreae, Hypericum gentianoides, Hypericum gymnanthum, Hypericum harperi, Hypericum majus, Hypericum mutilum, Hypericum paucifolium, Hypericum radfordiorum, Hypericum setosum, Hypericum virgatum

Key

1	Herbs annual, wiry; inflorescences: branching mostly monochasial	> 2
1	Herbs annual or perennial, not wiry; inflorescences: branching mostly dichasial	> 3
2	Leaf blades linear or linear-subulate to linear-lanceolate, 5–22 mm, margins recurved to revolute; sepals 3–7 mm; capsule lengths 1–1.2 times sepals.	Hypericum drummondii
2	Leaf blades narrowly triangular-subulate to linear-subulate, scalelike, 1–4 mm, margins incurved; sepals 1.5–2.5 mm; capsule lengths 2–2.7 times sepals.	Hypericum gentianoides
3	Stems and leaves scabrous-tomentose to pilose; sepal margins setulose-ciliate.	Hypericum setosum
3	Stems and leaves glabrous; sepal margins sometimes ciliate, not setulose-ciliate	> 4
4	Leaf blades linear-subulate, 0.2–0.3 mm wide, basal veins 1, midrib unbranched.	Hypericum cumulicola
4	Leaf blades not linear-subulate, (0.5–)2–18 mm wide, basal veins 1–7, midrib with 0–4 pairs of branches	> 5
5	Leaf blades leathery; petals golden yellow or orange-yellow; stamens (35–) 50–80	> 6
5	Leaf blades papery to membranous; petals usually bright, golden, or pale yellow, rarely salmon-orange; stamens 5–25	> 11
6	Leaf blades linear-oblong or linear-lanceolate to linear, 0.5–2 mm wide; petals red tinged; stamens 35–50; styles 2.5–5 mm	Hypericum paucifolium
6	Leaf blades elliptic, lanceolate, linear-lanceolate, oblong-elliptic, obovate, or ovate, 3–18 mm wide; petals not red tinged; stamens 50–80; styles 2–4 mm	> 7
7	Herbs erect or ± spreading, non-aerenchymatous at base; leaves (main stems) longer than internodes	> 8
7	Herbs erect to ascending, usually ± aerenchymatous (spongiform-thickened) at base; leaves (main stems) mostly shorter than internodes (usually longer in. 31 H. harperi).	> 9
8	Leaf blades (main stem) lanceolate to oblong-elliptic or obovate, 10–30(–50) mm, apex usually acute to acuminate, rarely obtuse; subsidiary inflorescence branches with or without relatively smaller leaves.	Hypericum virgatum
8	Leaf blades (main stem) narrowly lanceolate, 10–40(–55) mm, apex acute to acuminate; subsidiary inflorescence branches with relatively smaller leaves.	Hypericum radfordiorum
9	Herbs 2–7 dm; leaf blades (main stem) usually broadly to narrowly ovate, rarely elliptic or lanceolate.	Hypericum denticulatum
9	Herbs 3–12 dm; leaf blades (main stem) usually lanceolate, sometimes linear-lanceolate or oblong-elliptic, rarely elliptic or ovate	> 10
10	Herbs erect to ascending, branching at base and in inflorescence; leaves strongly ascending to appressed, shorter than internodes, smaller distally.	Hypericum erythreae
10	Herbs erect, branching (from long-creeping rhizomes) at base and from mid and distal nodes; leaves ascending to deflexed, mostly longer than internodes, not or scarcely smaller distally.	Hypericum harperi
11	Herbs decumbent to ascending, forming loose mats; stigmas scarcely capitate.	Hypericum anagalloides
11	Herbs usually erect, not forming loose mats; stigmas broadly capitate	> 12
12	Leaf blades lanceolate, linear, narrowly elliptic, narrowly oblong-elliptic, oblanceolate, oblanceolate-linear, or obovate; capsules broadest proximal to middle	> 13
12	Leaf blades usually elliptic, oblong, broadly oblong-elliptic, ovate, ovate-triangular, round, or suborbiculate, rarely lanceolate; capsules usually broadest at or near middle	> 14
13	Leaf blades lanceolate, narrowly oblong-elliptic, or oblanceolate, (2–)6–12 mm wide, basal veins (3–)5–7; inflorescences usually compact.	Hypericum majus
13	Leaf blades linear to oblanceolate-linear or (proximal) oblanceolate to obovate, 0.5–5.5 mm wide, basal veins 1–3(–5); inflorescences usually diffuse.	Hypericum canadense
14	Leaf blades (mid and distal) lanceolate-deltate, apex usually subacute; capsules narrowly conic-ellipsoid.	Hypericum gymnanthum
14	Leaf blades (mid and distal) elliptic, lanceolate, oblanceolate, oblong, round, suborbiculate, or ovate, apex obtuse to rounded; capsules narrowly ovoid to cylindric-ellipsoid	> 15
15	Leaf blades bicolor, paler abaxially; inflorescences: bracts linear-subulate.	Hypericum mutilum
15	Leaf blades concolor; inflorescences: bracts not linear-subulate.	Hypericum boreale