Lithocarpus lucidus (Roxb.) Rehder, J. Arnold Arbor. 1: 128 (1919)

Species name meaning "shining", referring to the acorn and upper leaf surface.

Cyclobalanus omalokos (Korth.) Oerst.
Lithocarpus omalokos (Korth.) Rehder
Pasania lucida (Roxb.) Gamble
Pasania omalokos (Korth.) Schottky
Quercus cuneata Roxb. ex Wall. [Invalid]
Quercus hasseltii Korth. ex Miq.
Quercus lucida Roxb.
Quercus omalokos Korth.
Synaedrys lucida (Roxb.) Koidz.
Synaedrys omalokos (Korth.) Koidz.

Large trees up to ca. 50 m tall and 120 cm diameter. Stipules present. Leaves alternate with short petiole, leaf blade fleshy, elliptic-obovate, hairless, pinnately veined with many inconspicuous secondary veins, margins curved downward, tip rounded, upper surface shiny. Male inflorescences in spikes of up to 20 cm long, female inflorescences slightly shorter. Fruit a nut with a diameter of ca. 3 cm that is less than half covered by the cupule. Cupule with spiral ridges.

Tree up to 50 m tall, 120 cm diameter; buttresses up to 1 m tall. Bark smooth, brown; inner bark granular, yellowish brown. Sapwood yellowish to brownish. Twigs glabrescent, sparsely lenticellate. Stipules linear, 2-3 x 1 mm. Leaves coriaceous, sometimes rigid, glabrous on both surfaces, shining above; oblanceolate, (4-)8-12(-16) x (2-)4-6(-8) cm, base cuneate, decurrent, margin revolute sometimes undulate, apex rounded, obtuse, acute to abruptly cuspidate; midrib faintly raised on both surfaces; lateral veins thin, (10-)14-16(-20) pairs, dense, flat on both surfaces or slightly raised below, faintly joining near the leaf margin, forming an angle of 40-60 degrees with the midrib; intercostal venation reticulate, dense, thin but distinct on both surfaces; petiole 2-7 mm long. Inflorescences male, female or androgynous. Male inflorescences 9-20 cm long; bracts and bracteoles ovate, 0.6-1 x 0.3-0.6 mm. Male flowers in clusters of 3-4 along the rachis; perianth lobes obtuse, c. 1 x 0.8 mm; stamen filaments c. 2 mm long; pistillode globose, c. 0.8 mm diameter. Female or androgynous inflorescences 10-20 cm long; bracts narrowly ovate, c. 1.4 x 0.3-0.6 mm; bracteoles broadly ovate, c. 1 x 0.9 mm. Female flowers solitary or in clusters of 3 along the rachis; perianth lobes acute, c. 1 x 0.7 mm; staminodes 10; styles conical, straight, c. 1.2 mm long. Cupules solitary but arranged closely together or sometimes in clusters of 3 along the rachis, sessile or with stalk c. 5 mm long, cupor saucer-shaped, 0.5-1(-1.5) x 2-3.5 cm, glabrescent, lamellate; wall woody, thick, glabrescent, enclosing half or less of the acorn; lamellae dense and distinct, edge minutely denticulate or undulate, set in 8-11 regular lines. Acorns depressed ovoid, 1.5-2.5 x 2-3.5 cm, most part exserted, glabrous and shining, brown purplish; base flat, apex rounded or acute; scar deeply concave 1.5-2 cm diameter; wall woody, thin, most part free from the cupule. [from Tree Flora of Sabah and Sarawak]

In primary hill mixed dipterocarp forest to lower montane forest, up to 1400 m altitude, on clay, sandy-clay and sandstone-derived soils.

The wood is locally used for house construction.

Sumatra, Peninsular Malaysia and Borneo.

Local names
Borneo: Sarusup tembaung (Dusun, Kimanis), Saled arong (Kelabit).