1. Hypericum L. (St. John’s wort)
Plants annual or
perennial herbs or shrubs. Young stems or twigs often angled, sometimes
narrowly 2-winged. Leaves sessile, the blades sometimes clasping at the base.
Flowers actinomorphic (except in H. hypericoides). Calyces of 4 or 5
sepals, these often persistent at fruiting. Corollas of 4 or 5 petals, these
yellow, less commonly orangish yellow, usually somewhat asymmetric at the tip,
sometimes withered but persistent at fruiting. Stamens 5 to more commonly
numerous, the filaments free, fused basally into a short ring around the ovary
base, or those of varying numbers of stamens fused basally into 3–5 sometimes
indistinct groups. Staminodes absent. Pistils of 2–5 fused carpels. Ovary
1-locular with parietal placentation, or completely or incompletely 3–5-locular
and then with more or less axile placentation. Style 1–5, if more than 1 then
the styles sometimes fused basally or closely appressed to each other most of
their length, the stigmas capitate or minute. Fruits capsules, narrowly to
broadly ovoid, ellipsoid, conical or nearly globose. Seeds numerous (except in H.
sphaerocarpum), tiny, ellipsoid-cylindrical to oblong-cylindrical. Three
hundred to 400 species, nearly worldwide, but most diverse in temperate regions
of the Northern Hemisphere.