Changes

*A medium-sized to large tree up to 45 m tall with low-branching bole up to 110 cm in diameter and prominent buttresses up to 2 m high; leaves .*Leaves broadly ovate, falcate with a subequal base, 8-15 cm × 3.5-8.5 cm, with 9-12 pairs of slender secondary veins prominent beneath; petals .*Petals narrow, stamens c. 30, appendages setose; fruit .*Fruit calyx lobes unequal, larger three up to 9 cm × 3 cm.  ''S. materialis'' occurs locally semi-gregarious and has become rare in Peninsular Malaysia as a result of logging. It occurs on giant podzols and sandstone cuestas in heath forest up to 800 m altitude. The density of the wood is 835-1040 kg/m³at 15% moisture content.