Mallotus nudiflorus (L.) Kulju & Welzen, Blumea 52: 124 (2007)

Name meaning 'naked flowers'.

Mallotus cardiophyllus Merr.
Rottlera hoperiana Blume ex Müll.Arg.
Rottlera indica Willd.
Rottlera operiana Blume ex Baill.
Trewia integerrima Stokes
Trewia macrophylla Roth
Trewia macrostachya Klotzsch
Trewia nudiflora L.
Trewia nudiflora var. tomentosa Susila & N.P.Balakr.

Large shrubs to trees up to 30 m high, dbh up to 50(–80) cm, dioecious, deciduous, flowering before or at the time of leaf appearance; Indumentum of simple to tufted hairs, short to long and soft, whitish to yellowish to brownish. Stipules (narrowly) triangular, 1.8–5.2 by 0.5–1.5 mm, early caducous. Leaves opposite to subopposite; petiole 1.8–12 cm long, often with a basal constriction when dry, glabrous to hairy, sometimes with glandular hairs; blade ovate, 6–21 by 6.3–16.5 cm, length/width ratio 1–2.3(–4.8 in immature leaves), papery, base cordate to obtuse, margin subentire (to rarely basally serrate with 1–7 minute teeth per side), apex (acute to) acuminate; basal extrafloral nectaries 2–5, 1–16 mm from petiole insertion, marginal extrafloral nectaries 0–8(–20) per side, 3–26 mm from margin; venation triplinerved (to 5-nerved), nerves 3–7 per side, looped and closed near the margin. Inflorescences axillary racemes, pendulous when staminate, single, or often 2 or 3 together when pistilate; staminate flowers many, (2 or) 3 (or 4) per node, pistillate flowers 1–5 at apical part, single per node; Staminate inflorescences up to 30 cm long. Staminate flowers: buds ovoid to ellipsoid; flowers 4.7–9 mm diam.; pedicels 3.9–10 mm long; sepals (2 or) 3 or 4, free, (ovate to) elliptic, (3.2–)3.7–6 by (1.8–)2.1–3.7 mm, light yellowish to light greenish. Pistillate inflorescences 1.5–10.5 cm long; bracts 1.2–3.2 by 0.5–2.1 mm. Pistillate flowers: pedicel 1.1–9 mm long, locules 3–5; style (1.7–)2.4–4.5(–5.9) mm long; stigmas 12–24 mm long, plumose inside, hairy outside. Fruits indehiscent, drupaceous, oblate (to spheroid), 18–29 by 21–35 mm when dry, up to 35 by 45 mm when fresh. Seeds in cross section somewhat triangular to almost elliptic, 8–12 by 7–10 by 6–8 mm, surface smooth, brown to black, with thin sarcotesta.

Deciduous to evergreen forest, usually disturbed and (partly) open sites, usually near streams and rivers, often on alluvial, but also on dry ground; bedrock varying (granite to limestone to shale to quartzite). In lowland Nepal M. nudiflorus is a common tree in riverine forests and dispersed by rhinoceros and domestic cattle (Dinerstein & Wemmer, Ecology 29, 1988, 1768-1774). Altitude up to 1200 m.

From India and Nepal throughout mainland Southeast Asia to southern China (Hainan, Yunnan) and West Malesia (Malay Peninsula, Sumatra, Borneo, Java, Philippines).

Wood is used for implements; leaves for fodder (Nepal). Medicinal uses: to remove swelling and bile, to relieve flatulence, for gout and rheumatic afflictions (India, Nepal).

Local names
Borneo: Pridja buaja.
Java: Binung putjang, Gemblok.