Croton   

Trees, shrubs or herbs, sometimes climbing, monoecious; branching usually verticillate; latex colourless or red. Indumentum consisting of stellate to lepidote, variously coloured hairs. Stipules linear to triangular, eglandular or with marginal glandular lobes, caducous. Leaves alternate to crowded, sometimes pseudo-verticillate; petiole distinct, eglandular, rarely glandular; blade simple, symmetric, variable in shape and margin, pubescent to a various degree, always with a pair of glands on the upper or lower base of blade or midrib or on the petiole apex, sometimes with additional marginal glands; venation usually visible on both surfaces, pinnate or palmate (triplinerved), side veins arching and hardly to distinctly looped (but always distinctly looped at the apex), tertiary veinlets percurrent to more often reticulate. Inflorescences terminal or subterminal, unbranched, elongate thyrses, bisexual, a basal part pistillate with 1 flower per bract, the apical part staminate with 1-3(-5) flowers per bract, more rarely completely pistillate or staminate, the pistillate flowers sometimes with lateral staminate flowers (with bisexual bracts); pubescent at least in parts; bracts triangular-ovate, glandular or eglandular, persistent or caducous. Flowers actinomorphic, pedicellate; sepals 5, ovate-elliptic, fused at base; petals 5, free. Staminate flowers: petals similar to sepals but less pubescent and with a ciliate-lanate margin; disc lobed, receptacle pilose (the flowers therefore filled with whitish hairs c. 1 mm long); stamens 10-20, inflexed in bud, free, filaments longer than the anthers, anthers 2-locular, basifixed; pistillode absent. Pistillate flowers pubescent at least in parts; petals much smaller than the sepals or more often absent; staminodes absent; ovary 3-locular, smooth or muriculate, always pubescent (in Thailand), with 1 ovule per carpel; style column short or absent, stigmas 3, bifid to a various degree, sometimes even quadrifid. Fruits 3-locular, small to large, nearly globose, usually sulcate, smooth or shallowly muriculate, pubescent (in Thailand), dry and dehiscent. Seeds 3 per fruit, dry, ellipsoid, brown, glabrous or (rarely) with scattered hairs, smooth, with or without a caruncle.
    Eight-hundred or more species, pantropical with the center of diversity (species and sections) in America; in Asia slightly less than 100 species, 30 species in Thailand. Classification: Subfamily Crotonoideae, tribe Crotoneae.
    N o t e.—  Natural subdivisions of this vast genus are still not well understood, in particular not in Asia.