Quercus gemelliflora Blume

Borneo, Java, Sumatra, W Malaysia; 600-2000 m;

tall tree 30 m and more; trunk to 0.60m in diameter;

15-17 x 3 cm; thin, chartaceous; lanceolate to oval-lanceolate ; apex acute, acuminate or caudate; base acute or attenuate, often asymmetrical; margin plane, serrulate towards apical 1/2; glabrous above; glabrescent beneath; 8-10 pairs of secondary veins weakly raised below, forming an angle of 40° with the midrib; petiole tomentose 1-4 cm long, flat above, glabrescent;

male catkins many-flowered, 3-6 cm long, hairy ; male flowers single or to 3, perianth 3-6-lobed, hairy, 3-6 stamens; female inflorescence 2-7-flowered, perianth 4-6-lobed, hairy, 0-6 staminodes, 4-6 styles 1-2 mm long;

acorn conical, 2-5 cm long, with obtuse apex and rounded base; most often paired along rachis; subsessile or on a short peduncle; cup enclosing 1/3 to 1/2 of nut, with 6-8 brownish, pubescent, denticulate rings;

not hardy; wet mixed forests;

– A. Camus : tome 1, p. 363, n° 81; – Sub-genus Cerris, Section Cyclobalanopsis; – Section Semiserrata, sub-section Gemelliflorae ( Menitsky ). – Strongly variable species (shape of leaves, pubescence of twigs, acorn); – For A.Camus, Q. horsfieldii Miq. is a synonym of Q. semiserrata ;