Botany
Evergreen, dioecious or rarely monoecious shrubs or small to medium-sized trees up to 25(-35) m tall; bole straight to sinuous, up to 50(-80) cm in diameter, occasionally with short or steep buttresses; bark thin, surface smooth, white or pale grey, inner bark fibrous, brown to reddish or dark red. Indumentum often of stellate hairs. Leaves arranged spirally or opposite, simple, entire, sometimes peltate, often whitish and with glandular granules below, venation pinnate or palmate; stipules small. Flowers in a terminal or axillary raceme or spike, unisexual; petals absent. Male flower with 3-4-lobed calyx; stamens numerous; disk absent, lobed or annular. Female flower with 3-5-lobed calyx; disk absent; ovary superior, (2-)3(-4)-locular with 1 ovule in each cell, styles elongate, simple or plumose. Fruit a lobed, thinly woody, smooth to echinate capsule, splitting into 2-valved parts and a persistant central column. Seed smooth, shiny black, sometimes with a small aril. Seedling with epigeal germination; cotyledons emergent, leafy; hypocotyl elongated; first few leaves arranged spirally, decussate higher up in species with opposite leaves.
In the Philippines a mean annual diameter increment of 1.4 cm has been recorded for M. philippensis trees in the diameter class 10-20 cm, whereas for M. mollissimus it is 1.7-1.9 cm and 3.6 cm for trees in the diameter classes 0-20 cm and 20-30 cm, respectively. In the Philippines M. philippensis flowers from March to April. M. philippensis has extrafloral nectaries attracting ants. The seeds of many Mallotus species are dispersed by birds.
Mallotus is closely related to Macaranga, the latter differing by its 3-4-celled anthers and more conspicuously by its lateral inflorescences and absence of stellate hairs.
Literature
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