Habit and leaf form. Shrubs, or herbs. Plants succulent, or non-succulent; unarmed. Perennial. Leaves cauline. Plants with a basal concentration of leaves, or with neither basal nor terminal concentrations of leaves. Stems not ‘jointed’. Young stems ridged. Stem internodes solid. Self supporting, or climbing. Helophytic to xerophytic. Leaves minute to large; alternate, or opposite; when alternate, spiral, or distichous; subcoriaceous; petiolate, or sessile; simple; epulvinate. Leaf blades entire; flat; linear, or ovate, or triangular; pinnately veined; hastate, or sagittate (narrowly), or rounded at the base (to truncate). Leaves without stipules. Leaf blade margins entire. Leaves without a persistent basal meristem. Leaf anatomy. Hydathodes present, or absent. Hairs leaves with vesicular hairs, at least below, when young.
Reproductive type, pollination. Fertile flowers hermaphrodite, or functionally male and functionally female, or hermaphrodite and functionally female. Unisexual flowers present, or absent. Plants hermaphrodite, or monoecious, or gynomonoecious. Female flowers without staminodes.
Inflorescence and flower features. Flowers aggregated in ‘inflorescences’; in cymes, or in racemes, or in fascicles (or clusters). The terminal inflorescence unit cymose. Inflorescences terminal, or axillary; terminal flower of each cluster bisexual, lateral flowers females. Flowers pedicellate, or sessile (constricted at apex); ebracteate; ebracteolate; minute, or small; regular; cyclic. Hypogynous disk present, or absent. Perianth sepaline; 5 (-4); 1 -whorled; joined (imbricate); fleshy, or non-fleshy; persistent; accrescent, or non-accrescent. Calyx present; not replaced by accrescent bracteoles; 5 (-4); gamosepalous; entire; imbricate; red (in fruit); non-fleshy; persistent (in the fruit); non-accrescent. The fruiting calyx not berrylike; wingless, spineless and without tubercles. Calyx lobes oblong. Corolla absent. Fertile stamens present, or absent. Androecial members definite in number. Androecium 1–3. Androecial members free of the perianth, or adnate (to the base of the perianth); all equal; free of one another; 1 -whorled. Androecium exclusively of fertile stamens. Stamens 1–3; all more or less similar in shape; isomerous with the perianth; oppositisepalous. Anthers bent inwards in bud; dehiscing via longitudinal slits; tetrasporangiate. Fertile gynoecium present, or absent. Gynoecium (2–)5 carpelled. The pistil 1 celled. Gynoecium syncarpous; synovarious to synstylovarious; superior. Ovary unilocular; 1 locular. Gynoecium stylate. Styles (1–)2–3(–4); partially joined. Stigmas 2. Placentation basal. Ovules in the single cavity 1; pendulous, or ascending; non-arillate; campylotropous.
Fruit and seed features. Fruit fleshy, or non-fleshy; indehiscent; capsular-indehiscent, or a berry; 1 celled. Gynoecia of adjoining flowers combining to form a multiple fruit, or not forming a multiple fruit. Fruit 1 seeded. Seeds more or less non-endospermic. Perisperm present, or absent. Cotyledons 2. Embryo curved (annular).
Etymology. Probably from the Greek for "one" and "man", in reference to the one or two stamens in the flowers of the type species.