Stewartia pteropetiolata W. C. Cheng

Trees 6-15 m tall, evergreen. Year-old branchlets purple, glabrous; current year branchlets grayish yellow pubescent. Petiole 1-1.5 cm, gray pubescent, wings ca. 3 mm wide; leaf blade elliptic to oblong, 6-10(-13) × 2.5-4.5(-5) cm, leathery, abaxially yellowish green, sparsely pubescent or glabrescent, and trichomes evident along midvein, adaxially green, shiny, and glabrous, midvein red, secondary veins 10-12 on each side of midvein, secondary and reticulate veins abaxially raised and adaxially impressed, base rounded, margin serrate, apex abruptly acute to shortly acuminate. Flowers solitary, ca. 3 cm in diam. Pedicel 8-10 mm, appressed pubescent; bracteoles persistent, elliptic, 5-7.5 × 3-3.5 mm, appressed pubescent. Sepals purplish red, long ovate, 1-1.5 × 0.7-1 cm, leaflike, both surfaces white sericeous, veins pinnate, margin serrulate, apex acute. Petals white, broadly obovate to suborbicular, 1.5-1.8 × 1-1.3 cm, outside basally white sericeous, apex rounded. Stamens 7-9 mm; filaments basally connate. Ovary ovoid, 3-4 mm, glabrous; style ca. 5 mm. Capsule long ovoid, 1.5-2 × 1-1.5 cm, 5-loculed with 4 seeds per locule; columella ca. 5 mm, apically abortive. Seeds obovate, ± compressed, ca. 5 × 3.5 mm, narrowly winged. Fl. Apr-May, fr. Sep-Nov. 2n = 36*.

S and W Yunnan.

● Forests; 1200-2600 m.

Hartia sinensis Dunn, Hooker’s Icon. Pl. 28: t. 2727. 1902, not Stewartia sinensis Rehder & E. H. Wilson (1915); Hartia serratisepala Hu.

Flowering from April to May; fruiting from September to November.

Stewartia pteropetiolata is close relative of Stewartia villosa, but differs from the latter in its serrulate sepals (vs. entire margin) margin, glabrous (vs. tomentose) ovary.

Stewartia pteropetiolata is occurring in S and W Yunnan of China.

Based on the morphology, palynology, anatomy, Li (1996) proposed a classification scheme for Stewartia, in which Stewartia pteropetiolata belong to Subgenus Stewartia, Section Pteropetiolatae.

Trees 6-15 m tall, evergreen. Year-old branchlets purple, glabrous; current year branchlets grayish yellow pubescent. Petiole 1-1.5 cm, gray pubescent, wings ca. 3 mm wide; leaf blade elliptic to oblong, 6-10 cm long, 2.5-4.5 cm wide, leathery, abaxially yellowish green, sparsely pubescent or glabrescent, and trichomes evident along midvein, adaxially green, shiny, and glabrous, midvein red, secondary veins 10-12 on each side of midvein, secondary and reticulate veins abaxially raised and adaxially impressed, base rounded, margin serrate, apex abruptly acute to shortly acuminate. Flowers solitary, ca. 3 cm in diameter. Pedicel 8-10 mm, appressed pubescent; bracteoles persistent, elliptic, 5-7.5 mm long, 3-3.5 mm wide, appressed pubescent. Sepals purplish red, long ovate, 1-1.5 cm long, 0.7-1 cm wide, leaflike, both surfaces white sericeous, veins pinnate, margin serrulate, apex acute. Petals white, broadly obovate to suborbicular, 1.5-1.8 cm long, 1-1.3 cm wide, outside basally white sericeous, apex rounded. Stamens 7-9 mm; filaments basally connate. Ovary ovoid, 3-4 mm, glabrous; style ca. 5 mm. Capsule long ovoid, 1.5-2 × 1-1.5 cm, 5-loculed with 4 seeds per locule; columella ca. 5 mm, apically abortive. Seeds obovate, ± compressed, ca. 5 × 3.5 mm, narrowly winged.

Growing in forests; 1200-2600 m.