Humiriaceae

Abstract

Evergreen trees or shrubs; wood often with balsamic juice; cork subepidermal; indumentum of simple hairs, usually sparse or 0. Leaves alternate, simple, involute, often distichous, penninerved, entire, crenulate or slightly serrate, petiolate or rarely sessile, sometimes decurrent along branches; stipules very small, lateral, caducous or 0. Inflorescences axillary or terminal, paniculate, often corymbiform, dichotomous or trichotomously branched, branchlets often articulate; bracts and prophylls small, amplectant, persistent or caducous. Flowers hermaphroditic, actinomorphic, pedicellate; sepals 5, ± connate, quincuncially arranged or imbricate, all of same size or 2 outer ones smaller; petals 5, caducous or sometimes persistent, distinct, white (red), contorted, cochlear or quincuncial; stamens numerous or in definite number of 10–30 and 1–2-seriate, alternating in length, sometimes the 5 antepetalous ones trifurcate at apex; filaments at base connate in a ± long tube; anthers dorsifixed or subbasifixed; thecae 2, bilocular and each cell dehiscing by longitudinal slit, or else 4 or 2, unilocular, dehiscing by detachment or sometimes by a slit; connective thick, fleshy, most commonly produced in an apiculum or linguiform appendix, or obtuse; some stamens occasionally staminodial; disk intrastaminal, girding the ovary, membranaceous or subcoriaceous, tubular or cupular, dentate, lobate, laciniate or composed of 10–20 distinct scales; gynoecium syncarpous, (4)5(−7)-carpellate, carpels opposite the sepals or rarely alternating with them; ovary ovoid or ellipsoid, (4)5(−8)-locular; placentation axile; ovules 1 or 2 per cell, pendulous, anatropous, epitropous, with the micropyle facing upwards and the raphe ventral, when 2 then superposed and the lower hanging from the longer funicle; style entire; stigma capitate, 5-lobate or 5-radiate. Fruit drupaceous; exocarp varying from pulpy to fibrous; endocarp woody, usually very hard, compact or containing many round, resin-filled cavities, rarely spongious-woody, (4)5(−7)-septate, with 1–2(−5) seeds developed; dehiscence germinal with longitudinal valves at the back of each carpel; subapical foramina alternating with valves often present. Seeds oblong, germinating enclosed in the fruit, retaining some nucellar remnants; embryo straight or slightly curved; endosperm fleshy and oily. x = 12.