四川大头茶 si chuan da tou cha

Thea speciosa Kochs, Bot. Jahrb. Syst. 27: 597. 1900; Camellia speciosa (Kochs) Cohen-Stuart; Gordonia acuminata Hung T. Chang (1983), not Zollinger (1854), nor S. Vidal (1886); G. axillaris (Roxburgh ex Ker Gawler) D. Dietrich var. acuminata E. Pritzel; G. kwangsiensis Hung T. Chang; Polyspora acuminata S. X. Yang; P. kwangsiensis (Hung T. Chang) C. X. Ye ex S. X. Yang.

Trees 5-15 m tall. Current year branchlets stout, glabrous or subglabrous; terminal buds purplish red, 1-1.5 cm, glabrous or white sericeous. Petiole purplish, (0.8-)1.5-2 cm, glabrous; leaf blade elliptic to oblong-elliptic, (9-)10-18(-22) × 3-6(-7) cm, leathery, abaxially pale green, adaxially dark green and shiny, both surfaces glabrous, midvein abaxially elevated and adaxially impressed, secondary veins obscure or slightly visible on both surfaces, base cuneate and decurrent, margin apically serrate to sometimes crenate-serrate, apex acuminate to sometimes bluntly acute. Flowers axillary and solitary, (5-)8-10 cm in diam. Pedicel ca. 3 mm, gray velutinous; bracteoles 5, caducous. Sepals 5, broadly ovate to suborbicular, 8-10 mm in diam., outside purplish brown but basally yellowish velutinous. Petals 5, white, broadly obovate, 3-5 cm, basally connate for ca. 3 mm, apex emarginate. Stamens 2-2.5 cm; filaments glabrous, basally adnate to petals. Ovary ovoid, white tomentose, 5-loculed; style 1.5-2 cm, white velutinous; stigma 5, slightly furcate. Capsule oblong-cylindric, (2.5-)3-3.5 × 1-1.5 cm, with ca. 5 seeds per locule; pedicel to 1 cm in fruit. Seeds together with wing 2-2.5 × ca. 0.5 cm. Fl. Aug-Nov, fr. Sep-Dec.

Forests, thickets; 1200-2100 m. Chongqing, Guangxi, Guizhou, Hunan (Jianghua), S and SW Sichuan, NE, SE, and SW Yunnan [Vietnam].

This species was described from collections in Chongqing Municipality where the plants have larger, more deeply serrate leaf blades. Plants from farther south, particularly in SE Yunnan and S Guangxi, have smaller leaf blades that are more shallowly serrate as well as smaller flowers, and the name Polyspora tonkinensis (Pitard) B. M. Bartholomew & T. L. Ming (Gordonia tonkinensis Pitard) has been misapplied to them (Ming, Fl. Yunnan. 8: 316. 1997; Bartholomew & Ming, Novon 15: 266. 2005; Yang, J. Trop. Subtrop. Bot. 14: 365. 2005).