老挝柯 lao wo ke

Pasania laotica Hickel & A. Camus, Ann. Sci. Nat., Bot., ser. 10, 3: 402. 1921.

Trees to 20 m tall. Branchlets of current year blackish when dry; branches of previous year growth and rachis of infructescences conspicuously lenticellate. Petiole 1.5-2.5 cm; leaf blade elliptic to lanceolate, 12-20 × 4-9 cm, ± rigidly papery, abaxially light gray and with adherent, waxy scalelike trichomes, adaxially dark gray when dry, base broadly cuneate to acute, margin entire, apex narrowly acuminate to acute; secondary veins 10-13 on each side of midvein, sometimes fusing near margin on apical part of leaf; tertiary veins abaxially ± visible. Male inflorescences terminal clusters on branchlets of current year, 4-10 cm; rachis pubescent. Female inflorescences 10-15 cm; cupules in clusters of ca. 3. Infructescence rachis base 4-6 mm thick. Cupule subglobose, ca. 3.5 × 2-2.5 cm, completely enclosing nut, with many concentric ridges and inconspicuous bract scars between ridges, wall ca. 1.5 mm thick; bracts scalelike. Nut subglobose, 2-2.5 × 1.6-2.2 cm in diam., glabrescent, apex rounded, wall less than 1 mm thick; scar covering more than 1/2 of nut, convex. Fl. Mar, fr. Sep of following year.

Broad-leaved evergreen forests; 1500-2200 m. SE Yunnan [N Laos, Vietnam]

According to A. Camus (Chênes 3: 587. 1953), the typical mature leaf blades are leathery and adaxially oily when dry, the tertiary veins are abaxially inconspicuous, and the nut apex is flat.