Description

Key Characters:

Growth Form: Perennial herbs or rarely subshrubs.

Stems: Stems pseudodichotomous, nodes usually prominent.

Roots:

Leaves: Leaves simple. Opposite. Leaf pairs often unequal in size. Margins entire or nearly so. Petiolate or upper ones sessile. Stipules absent.

Flowers: Flowers 1–10 in open or congested, cymose inflorescences, ultimate branches bearing involucres. Involucres of 4–5 connate bracts. Flowers bisexual (perfect). Perianth corolloid, usually constricted somewhat above the ovary, limb funnelform, campanulate, or rotate. Corolla (petals) absent. Stamens 3–5, basal; filaments distinct or connate at base; anthers didymous, usually exserted. Ovary superior, ellipsoid or globose, 1-celled, closely invested by lower part of perianth; ovule 1, basal; style 1, filiform; stigma capitate, exserted.

Fruit: Anthocarps ovoid–ellipsoid to oblong; globose; or obovoid; terete (cylindrical) to slightly 5–angled; adherent to testa of the seed; the surface smooth to variously rugose. Seeds 1 per fruit; closely enclosed by the thin ovary wall.

Ploidy:

Habitat:

Elevation Range: