Castanopsis tungurrut A.Dc.

Tree, 20-25 m by 60 cm ø; bark rough, fissured. Branchlets initially with fulvous tomentum, later glabrescent, rather sturdy, dull greyish black, smooth, sparsely lenticellate; terminal bud ovoid-ellipsoid, 3-5 by 2-3 mm, scales ovate, elliptic, acute, 3-4 by 2 mm. Stipules boat-shaped, ovate-triangular, 4-6 by 2-3 mm. Leaves (8-) 12-15(-23) by (3½-)5-6(-9) cm (index 2-3), widest about the middle to slightly below; base rounded-acute, sometimes asymmetrical, top tapering and subacu-minate; more or less discolorous, above rather glossy, green-brownish, glabrous, beneath dull with a faint greyish tinge, densely covered with a waxy mass in which stellate scales are very closely adpressed (magnification 60!), and also with some longer hairs (the latter in Sumatra almost wanting); midrib prominent on both surfaces, stronger beneath; nerves 11-19 pairs at an angle of 60-70°, parallel, arcuating and disappearing near the margin, prominent beneath, flattish above; reticulation fine, dense, scalariform, sometimes obscure above; petiole (½-)l-1½(-2) cm, adaxially flat or shallowly sulcate. Inflorescences male, female, or androgynous. Male rachis 10-25 cm by 1-2 mm; bracts and bracteoles ovate-acute, 2-3 by 1-1½ mm, hairy outside; ♂ flowers in clusters of 3, perianth deeply incised, lobes 5-6, acute, 2-2½ by 1-1½ mm, hairy on both sides, stamens 10-12, filaments 3-4 mm, anthers 0.2-0.25 mm long, pistillode 1½ mm ø. Female or androgynous rachis 5-15 cm, bracts thick-coriaceous, ovate-acute, 2-2½ mm, densely hairy outside; ♀ flowers solitary, perianth lobes 5-6, acute, 0.7-1 mm, densely hairy, staminodes 12, rudimentary, styles 3, conical, recurved, 2-2½ mm. Young cupule sessile, ovoid, on the rounded lateral sides with spine-like tubercles, on the flat median sides scaly. Ripe cupule subsessile, obovoid-ellipsoid, 5-6 by 3-4 cm; wall 1-2 mm thick, covered partly with fulvous puber-ulence, and mostly all over with scattered bundles of slender spines branched in the basal half and easily reflexed 10-23 mm long, sparsely puberulous; dehiscence none or irregular. Fruit solitary, ovoid-ellipsoid, 3-4 by 1½-2 cm, wall 1 mm thick, completely adnate to the cupule, when ripe rugose and glabrous; cotyledons flat-convex.

It is a tropical plant. It grows in lowland forests and up to 1,500 m above sea level.

The seed is roasted and eaten.

Plants can be grown from seeds.