Lithocarpus leptogyne (Korth.) Soepadmo, Reinwardtia 8 (1970)

Latin for 'thin female parts', referring to the female inflorescences.

Synonyms
Cyclobalanus leptogyne (Korth.) Oerst
Quercus leptogyne Korth.

Diagnostics
Mid-canopy tree up to 40 m tall and 90 cm dbh. Stipules ca. 5 mm long. Leaves alternate, simple, penni-veined, hairy below, often with long elongate drip tip. Flowers ca. 3 mm diameter, green-yellow, placed in racemes. Fruits ca. 16 mm diameter, greenish, nut with basal cupule.

Description
Tree up to 40 m tall, 90 cm diameter; buttresses up to 1.5 m tall. Bark smooth or lenticellate, greyish; inner bark granular, brownish. Sapwood yellowish. Twigs densely tomentose with stellate hairs, sparsely minute-lenticellate. Stipules linear, 3-6 x 1 mm. Leaves coriaceous, sparsely yellowish tomentose with stellate and simple hairs on both surfaces; elliptic, lanceolate, or elliptic-oblong, (7.5-)12-16(-19) x (2.5-)3.5-4.5(-6.5) cm, base acute, rarely rounded, margin revolute, apex acuminate, acumen 10-15(-20) mm long; midrib thin, raised on both surfaces; lateral veins thick, 11-14(-18) pairs, dense, impressed or flat above, raised below, clearly joining near the leaf margin, forming an angle 30- 60 degrees with the midrib; intercostal venation subscalariform, lax, obscure above, prominent below; petiole 6-8(-10) mm long. Inflorescences male, androgynous or mixed. Male inflorescences 10-20 cm long; bracts ovate, c. 0.7 x 0.5 mm; bracteoles broadly ovate, c. 0.5 mm across. Male flowers solitary along the rachis; perianth lobes obtuse, c. 0.7 x 0.5 mm; stamen filaments 2-3 mm long; pistillode subglobose, c. 1 mm diameter. Androgynous or mixed inflorescences 6.5-10 cm long; bracts and bracteoles ovate, c. 1 x 0.5 mm. Female flowers solitary along the rachis; perianth lobes acute, 0.5-0.7 mm across; staminodes 12; styles conical, slightly recurved, c. 1 mm long. Cupules solitary along the rachis, with stalk c. 5 mm long, saucer-shaped, 0.3-0.8 x 1.3-2 cm, densely tomentose, scaly; wall woody, thick, densely tomentose, enclosing less than half of the acorn; scale-like appendages distinct, appressed, dense, regularly set. Acorns conical, 1.2- 2 x 1.5-2 cm, most part exserted, densely simple-hairy, brownish or purplish; base rounded, apex acute; scar deeply concave or flat, c. 1.2 cm diameter; wall woody, thin, most part free from the cupule. [from Tree Flora of Sabah and Sarawak]

Ecology
In undisturbed mixed dipterocarp and swamp forests up to 1800 m altitude. On alluvial sites and along rivers, but also common on hillsides and ridges. Usually on sandy soils, but also on clay and limestone.

Distribution
Peninsular Malaysia, Sumatra, Borneo.

Local names
Borneo: Barangan, Bening peningan, Berangan, Empili, Kalan (Berawan), Mempening, Miakak, Pampaning, Pening-peningan (Kedayan), Tembadang, Tikalod (Dusun, Bundu Tuhan), Turug (Sungai).