短柱金丝桃 duan zhu jin si tao

Hypericum patulum Thunberg var. hookerianum (Wight & Arnott) Kuntze; Norysca hookeriana (Wight & Arnott) Wight.

Shrubs, to 1.75 m tall, bushy, round-topped; branches erect to spreading. Stems 4-lined and ancipitous when young or always terete; internodes 1.2-6 cm, shorter than to exceeding leaves. Leaves with petiole 1-4 mm; blade narrowly lanceolate to oblong-lanceolate or broadly ovate, (1.7-)2.5-7.8 × (0.7-)1-3.2 cm, abaxially paler or ± glaucous; laminar glands short streaks to dots; abaxial glands dense to sparse or absent; main lateral veins (2 or)3- or 4-paired, without visible tertiary reticulation; base narrowly cuneate to subcordate, apex acute to rounded. Inflorescence 1-5-flowered, from apical node, nearly round-topped; bracts deciduous, lanceolate or narrowly oblong to obovate-spatulate. Pedicels 3-16 mm. Flowers 3-6 cm in diam., ± deeply cupped; buds broadly ovoid to subglobose, apex broadly obtuse to rounded. Sepals spreading-incurved, obovate or obovate-spatulate to subcircular or elliptic or oblong-elliptic, subequal, 5-10 × 4-8 mm; laminar glands lines, sometimes interrupted near apex, often becoming impressed (sepals apparently ribbed) margin entire or rarely very finely eroded-denticulate, apex rounded or rarely rounded-apiculate to obtuse. Petals deep golden to pale yellow, broadly obovate to subcircular, 1.5-3 × 1.5-2.5 cm, ca. 3 × as long as sepals; margin entire, eglandular; apiculus obtuse to rounded or absent. Stamen fascicles each with 60-80 stamens, longest 5-9 mm, 0.25-0.35 × as long as petals. Ovary broadly ovoid, 5-7(-8) × 4-5(-6) mm; styles 2-4(-7) mm, 0.35-0.7(-0.9) × as long as ovary, free, gradually outcurved toward apex. Capsule ovoid to ovoid-conic, 0.9-1.7 cm × 7-12 mm. Seeds dark reddish brown, 0.7-1 mm, not or scarcely carinate; testa linear-reticulate. Fl. Apr-Jul, fr. Sep-Oct. 2n = ?20.

Thickets on slopes, forest margins; 1900-3400 m. S and SE Xizang (Yadong, Zayü) [Bangladesh, Bhutan, NE and S India, Myanmar, Nepal, N Thailand, N Vietnam].

Hypericum hookerianum is a widespread and variable species. The Xizang population, like those from adjacent (Himalayan) regions, has ovate leaves and rounded sepals. Plants in both areas, however, have the broad sepals with prominent, linear glands characteristic of the species.