Acer sikkimense Miq.

Trees to 20 m tall, andromonoecious. Bark black-gray. Branchlets brown, glabrous; winter buds ellipsoid, large, scales 4 pairs, glabrous. Leaves deciduous; petiole 2-4 cm, glabrous, leaf blade abaxially pale green, adaxially dark green, ovate or ovate-oblong, 10-14 × 5-8 cm, papery, abaxially with barbed hairs at vein axils when young, glabrescent, adaxially glabrous, base subcordate or nearly rounded, undivided, margin entire or nearly entire, sometimes serrulate, apex caudate. Inflorescence terminal, racemose, 40-50-flowered. Pedicel ca. 2 mm, glabrous. Sepals 5, oblong-ovate, ca. 3 mm, apex obtuse. Petals 5, yellowish green, ca. as long as sepals. Stamens 8, glabrous, rudimentary in pistillate flowers; anthers pale yellow. Disk glabrous, intrastaminal. Ovary glabrous; style very short; stigmas widely spreading. Fruit brownish when mature; nutlets flat, ovate-oblong, ca. 8 × 5 mm; wing falcate, including nutlet 2-2.5 cm × ca. 8 mm, wings spreading obtusely, rarely horizontally. Fl. Mar, fr. Sep. 2n = 26.

E. Himalaya (Nepal to NEFA).

E. Himalaya (Nepal to Bhutan), Assam. S. Tibet, N. Burma, W. China.

SE Xizang, Yunnan [Bhutan, N India, N Myanmar, Nepal].

2300 m

1800-2100 m

Mixed forests; 1700-3000 m.

Acer hookeri Miquel; A. hookeri var. normale Schwerin; A. hookeri var. orbiculare W. P. Fang & Y. T. Wu; A. medogense T. Z. Hsu & Z. K. Zhou; A. pluridens T. Z. Hsu & H. Sun; A. sikkimense subsp. hookeri (Miquel) Wesmael; A. sikkimense var. serrulatum Pax; A. sikkimense var. subintegrum Schwerin.

Acer sikkimense is a rare Asian species of maple. It is native to the Himalayas and nearby mountains in Sikkim, Bhutan, Nepal, northern India, Myanmar, Tibet, and Yunnan.

Acer sikkimense is a deciduous tree up to 20 meters tall with dark gray bark. Leaves are non-compound, up to 14 cm wide and 8 cm across, thin and papery, with no lobes, but sometimes with small teeth along the edges.