Changes

*''Hopea nabirensis'' v. Slooten (1952).

*A large tree of up to 48 m tall, bole cylindrical, branchless for up to 30 m, with a diameter of up to 100 cm and flying buttresses, bark surface flaky, blackish, inner bark pale yellow or light brown, sapwood pale straw-coloured, heartwood dark brown; young parts buff puberulent; leaves .*Leaves lanceolate-falcate, 5-13 cm × 2-4.5 cm, leathery, dull greyish minutely stellate beneath, base unequal, cuneate, acumen slender, up to 1.5 cm long, margin frequently subrevolute, venation scalariform, secondary veins 7-11 pairs, slender but distinctly elevated beneath, slightly elevated above; stamens .*Stamens 15, in 3 subequal verticils, ovary and stylopodium conical-cylindric, sericeous, style short, columnar; all .*All fruit calyx lobes saccate, 2 longer ones up to 7 cm × 1.8 cm, broadly spatulate, obtuse, 3 shorter ones up to 6 mm × 4 mm, ovate, acute.  ''H. iriana'' is very variable showing regional variants. It occurs in evergreen forest on hills, especially on ridges at up to 600 m altitude. The density of the wood is about 1000 kg/m³at 15% moisture content. See also the table on wood properties.