十蕊枫 shi rui feng

Acer chionophyllum Merrill; A. decandrum Merrill; A. garrettii Craib; A. laurinum subsp. decandrum (Merrill) A. E. Murray; A. laurinum var. petelotii (Gagnepain) Phamhoang; A. longicarpum Hu & W. C. Cheng; A. macropterum T. Z. Hsu & H. Sun (1997), not Visiani (1860); A. niveum Blume; A. philippinum Merrill.

Trees evergreen, to 30(-48) m tall, androdioecious, sometimes andromonoecious. Bark gray. Branchlets green, glabrous; winter buds ovoid, scales 7-11 pairs. Petiole (1.5-)3-6(-10) cm, glabrous; leaf blade abaxially glaucous, whitish or light blue-gray, adaxially glossy dark green, lanceolate or oblong-elliptic to ovate, 9-15 × 3-8 cm, abaxially ± pubescent, trinerved, lateral veins 5 or 6 pairs, 2 basal veins reaching beyond middle of blade, base rounded or cuneate or broadly cuneate, margin entire, glabrous, apex shortly acuminate to obtuse. Inflorescence cymose-paniculate, appearing in axils of fallen leaves, 2.5-10 cm, glabrous or pubescent; peduncle 5-35 mm. Pedicel 4-17 mm, glabrous. Flowers pale yellowish. Sepals 5, ovate, 2.5-3 mm, glabrous. Petals 5, 1.5-2.5 mm. Stamens (4-)8-12, glabrous; filaments ca. 5 mm in staminate flowers, ca. 2.2 mm in pistillate flowers. Disk amphistaminal, glabrous. Ovary rudimentary in staminate flowers. Samara brownish yellow; strongly veined; nutlets slightly convex, ca. 15 × 7 mm, pubescent or nearly glabrous; wing falcate, broadest near apex, including nutlet 4-7 × 2-3 cm, wings spreading acutely. Fruit peduncle 1-3 cm, stout. Fl. Jun-Sep, fr. Sep-Dec. 2n = 26.

Evergreen forests, scattered; 700-2500 m. SW Guangxi, Hainan, SE Xizang, NW and S Yunnan [Cambodia, S India, Indonesia, Laos, Malaysia, Myanmar, Philippines, Thailand, Vietnam].

The only true tropical maple spreading to the S Hemisphere, this species is relatively rare.