Description from Flora of China
Acer dielsii H. Léveillé; Dipteronia sinensis f. taipaiensis (W. P. Fang & M. Y. Fang) A. E. Murray; D. sinensis var. taipeiensis W. P. Fang & M. Y. Fang.
Trees ca. 16 m tall. Branchlets purple or purplish green; winter buds pubescent. Leaves deciduous, 20-40 cm; leaflets usually 7-11, proximal pairs shortly petiolulate, apical pair subsessile, terminal leaflet with petiolule 1-2 cm; leaflet blades abaxially light green, adaxially dark green, oblong-ovate to oblong-lanceolate, 7-10 × 2-4 cm, papery, abaxially glabrous or puberulent, adaxially glabrous, lateral veins 10 or 11 pairs, glabrous, with tufts of hairs at axils of veins, or pubescent, base rounded or broadly cuneate, margin remotely serrate, teeth acute or ± acute, apex acuminate or long acuminate. Inflorescence terminal or axillary, erect, glabrous or gray puberulent, 15-30 cm; peduncles 3-5 cm. Flowers ca. 2.5 cm in diam.; pedicel glabrous. Sepals 5, ovate or elliptic. Petals 5, white, broadly ovate, ca. 1 × 1.5 mm, alternate with sepals. Filaments glabrous, much longer than petals. Ovary compressed, hirsute, 2-loculed, rudimentary in staminate flowers; style short; stigmas revolute. Pedicels ca. 1 cm, slender, glabrous. Nutlets connate at base and encircled by an orbicular or obovate wing, 0.2-2.5 × 1.7-2.3 cm, hirsute when young, glabrescent. Seeds nearly orbicular, ca. 5 mm in diam. Fl. Apr, fr. Sep. 2n = 18*.
● Mixed forests, forest margins; 1000-2400 m. SE Gansu, N Guizhou, SW Henan, W Hubei, Hunan, Shaanxi, S Shanxi, E Sichuan.