Tree 4-25 m. Leaves membranous to (thinly) coriaceous, (elliptic-)oblong, 5—12(—17) by 2-4 cm, base attenuate, apex acute-acuminate or rounded, upper surface drying olivaceous to blackish brown, lower surface early glabrescent; Inflorescences with sparse hairs 0.1 mm; Fruits 2-6 per infructescence, ovoid-ellipsoid, 1.1-2 by 0.9-1.6 cm, apex (narrowly) rounded, base rounded, glabrous, finely wrinkled or granulate, without tubercles;
Asia-Tropical: Borneo present (Sarawak present); Malaya (Peninsular Malaysia present); Sumatera (Sumatera present), E Kalimantan present
Malesia: Sumatra, Peninsular Malaysia, Borneo (Sarawak, E Kalimantan); 2 subspecies.
Horsfieldia penangiana can be recognized by the slender twigs with ± small, dotted leaves, very short hairs on leaf buds and inflorescences, globose or ellipsoid male buds, and by an ellipsoid androecium which is (sub)circular in cross section. In habit it resembles Gymnacranthera eugeniifolia. Sterile specimens may also recall//, ridleyana. Taxonomically H. penangiana seems close Co H. glabra, especially Its var. javanica.