Aporosa nervosa Hook.f., Fl. Br. Ind. (1887)

Latin for 'with clear venation'.

Aporosa sphaeridiophora var. pubescens J.J.Sm.

Sub-canopy tree up to 21(-30) m tall and 33(-45) cm dbh. Stipules ca. 9 mm long. Leaves alternate, simple, penni-veined, hairy below. Flowers ca. 0.3 mm in diameter, yellow, placed in racemes. Fruits ca. 11 mm long, yellow, dehiscent capsules, seeds with aril.

Tree, up to 30 m high, up to 45 cm diameter. Bark dark chocolate brown to reddish brown to light brown or grey, smooth, slightly fissured and flaking, 4-5 mm thick; inner bark pink, or dull or reddish brown, c. 5 mm thick. Wood cream, yellow, or pale to dull orange-brown. Exudate watery, resinous, sticky. Young branches (sparsely) puberulous. Stipules narrowly ovate, slightly oblique, 7-10 by 3-5 mm, (sparsely) tomentose, caducous. Petiole terete, smooth, 8-21 by 0.8-1.2 mm, (sparsely) puberulous, lower pulvinus 1.5-3 by 1.2-1.8 mm, upper pulvinus 2-5 by 1.2-2 mm, both distinct. Leaves (narrowly) elliptic, 8.5-21 by 2.5-8 cm; base obtuse to attenuate, basal glands absent; margin lowly undulate to lowly glandular-crenate, marginal glands regular, large, black; apex acuminate to cuspidate; blade thickish, smooth, dull, older leaves brittle, drying greenish grey to greenish blue above, greyish brown beneath, only midrib at base very sparsely puberulous above, very sparsely hirsute beneath, glabrescent, midrib and nerves (sparsely) hirsute; dots densely set, large, black, distinct, fading; disc-like glands absent. Nervation: midrib slightly prominent to flat above, prominent beneath; nerves 6-9 pairs, slightly prominent to flat above, prominent beneath, marginal arches often distinct, 1-3 mm from the margin; veins and venation fading, rather laxly reticulate, slightly scalariform, flat above, (slightly) prominent beneath. Inflorescences axillary or just below the leaves. Staminate inflorescences 1-3 clustered together, 14-57 by 1.5-2 mm, puberulous; peduncle 2-4 by 0.8-1 mm; bracts inconspicuous, triangular, 1.2-1.5 mm long, sparsely hairy outside, glabrous inside, margin ciliate; glomerules subglobose, lax, consisting of 6-10 flowers, 1.5-2 by c. 1.5 mm, spaced at 2-3 mm at base, decreasing to 0 mm at apex; pedicel minute. Staminate flowers 2-3 mm long; sepals 4, obovate, ridged, 1.2-1.5 mm long, connate to c. halfway, sparsely hairy outside, glabrous inside, margin ciliate; stamens 3 or 4, exserted, 2-3 mm long; anthers 0.3-0.4 mm long, connective sparsely hairy; pistillode absent. Pistillate inflorescences 1 or 2 clustered together, 5-9 by 0.8-1.2 mm, (sparsely) puberulous, the flowers up to 9, rather densely arranged throughout, more densely so apically; bracts triangular, 0.7-0.9 mm long, sparsely hairy outside, glabrous inside, margin ciliate; bracteoles triangular to ovate, 0.4-0.6 mm long, sparsely hairy outside, glabrous inside; pedicel 0.8-1 mm long, (sparsely) puberulous. Pistillate flowers 2-3 mm long; sepals 4, ovate, patent, 0.8-1.2 mm long, at base sparsely hairy outside, glabrous inside; ovary ellipsoid, 1.5-2.5 mm long, 2-, 3- (or 4-)locular, smooth, (sparsely) puberulous, glabrescent towards apex; stigmas sessile, elongated, apically bifid to near base, perpendicular to the sides of the ovary, slightly recurved, 0.8-1.2 mm long, smooth above, margins lowly laciniate, glabrous, smooth beneath, sparsely hairy, style remnant present. Infructescences 7-32 by 1-1.8 mm, (sparsely) puberulous; fruiting pedicel 2-8 mm long, (sparsely) puberulous. Fruits ellipsoid to globose, not stiped, not beaked, 10-22 by 9-13 mm, rather smooth, sparsely hairy; pericarp 0.8-1.5 mm thick, not fleshy; septae and column glabrous. Seeds 1-3, half-terete, ellipsoid, 7-9 by 5-6 by 2-3 mm. [from Flora Malesiana: http://www.nationaalherbarium.nl/Euphorbs/specA/AporosaT.htm]

Primary and secondary mixed dipterocarp forest; lowland, high, or alluvial forest; flat or undulating land, on hill sides, ridges, near swamps, along river banks. Soil: clay, sandy loam, granitic sand, black or red. Altitude: 20-1000 m.

Peninsular Thailand, Peninsular Malaysia, Sumatra, Java, Borneo.

Local names
Borneo Stondong darod.
Sumatra Rangkap (Tamuk); semasan lanang, semasan betino (Palembang).