Castanopsis megacarpa Gamble, Kew Bull. (1914)

Diagnostics
Tree with buttresses, bark smooth to shallowly fissured. Twigs densely hairy when young, sparsely lenticellate. Stipules ca. 4 mm long. Leaves alternate, simple, up to 25 by 10 cm, penni-veined, lower leaf browninsh, margin entire. Male flowers ca. 2 mm diameter, green-yellow, placed in racemes. Fruits ca. 90 mm long, greenish, nut completely enclosed by cupule, splitting irregularly or in two parts, completely covered with long spines up to 1.5 cm.

Description
Tree, 12-48 m by 30-90 cm diameter; buttresses up to 2 m tall; bark surface smooth or shallowly fissured, pale greyish brown. Branchlets initially densely set with reddish brown adpressed stellate tomentum, later greyish brown, sparsely lenticellate; terminal bud ovoid-globose, 3-5 by 3-4 mm, scales ovate-acute. Leaves thick-coriaceous, lanceolate-oblong or elliptic-oblong, 10-25 by 3-10 cm; surfaces strongly discolorous, above glabrous, glossy, greyish green, underneath with a thick cover of reddish brown adpressed stellate hairs; base rounded or acute, sometimes asymmetrical, margin entire recurved, apex rounded or abruptly acute; midrib and nerves prominent beneath, flattish above; nerves 8-16 pairs, parallel, ascending, at an angle of 60-70 degrees, arcuating but not anastomosing near the margin; reticulation fine, subscalariform, obscure on both surfaces; petiole subglabrous, thickened and rugose at the base, adaxially flat or shallowly furrowed, 1.5-2.5 cm by 2-3 mm. Male rachises 10-20 cm, in paniculate clusters; bracts ovate-acute; male flowers in clusters of 3, perianth deeply incised, lobes 6, acute, 1-2 mm, stamens 12, filaments 3.5-4 mm, anthers 0.20- 0.25 mm long, pistillode rounded, c. 1 mm diameter. Female rachis 1 0-1 5 cm ; female flowers solitary, ovary rounded triangular in cross-section, 3-locular, perianth 6-lobed, staminodes 12, rudimentary, styles 3, terete, c. 1 mm, recurved. Ripe cupule ovoid-globose, subsessile, 8-10 by 6-7 cm; wall woody, 2-4 mm thick; spines much-branched, 1-1.5 cm long, with sharp tip, rigid, densely but irregularly set; dehiscence into two equal halves or irregular. Fruit solitary, ovoid, 6-8 by 3-5 cm, wall woody, 3-4 mm thick, rugose, adnate to the cupule; cotyledons flat-convex. [from Flora Malesiana]

Ecology
In undisturbed mixed dipterocarp to sub-montane forests up to 1500 m altitude. Often along rivers, but also common on hillsides and ridges. Usually on sandy soils, including those of kerangas.

Uses
The bark is locally used as wall division in long houses, for making bowls and other domestic utensils.

Distribution
Peninsular Malaysia, Borneo.

Local names
Borneo: Barangan, Berangan, Damar mata kidjing, Ponip, Tugoh.