Acer chienii Hu & W. C. Cheng

This species is similar to Acer pectinatum subsp. taronense, but the fruit is much smaller, and the leaves are 3-lobed in the upper part. However, one of us (Chen) believes that the size of the fruit and the number of leaf lobes are variable within taxa of A. sect. Macrantha.

Trees to 17 m tall, andromonoecious. Bark smooth. Branchlets green or purplish, glabrous; winter buds ellipsoid, glabrous. Leaves deciduous; petiole 3-4 cm, nearly glabrous; leaf blade ovate or ovate-oblong, 9-13 × ca. 8 cm, papery, abaxially densely rufous pubescent on veins, adaxially glabrous, base subcordate, margin doubly serrulate with adpressed acute teeth, 3-lobed; middle lobes triangular-ovate, apex acuminate; lateral lobes in upper part of blade, much shorter and apex acute. Inflorescence terminal on leafy branchlets, appearing after leaves develop, simple racemose, 6-8 cm, 15-40-flowered. Pedicel ca. 4 mm, slender. Staminate flowers: sepals 5, oblong, glabrous, apex obtuse; petals 5, obovate, apex obtuse; stamens 8, glabrous; disk glabrous, intrastaminal; ovary rudimentary. Samara wing including nutlet 1.4-1.8 cm × 4-6 mm, wings spreading obtusely. Fl. Apr, fr. Aug-Oct.

NW Yunnan.

● Mixed forests; 2200-3000 m.

Acer tegmentosum Maximowicz f. rufinerve A. E. Murray.

怒江槭（学名：Acer chienii）是无患子科槭属的植物。分布在缅甸北部以及中国大陆的云南省等地，生长于海拔2,500米至3,000米的地区，多生长在疏林中，目前尚未由人工引种栽培。