Hypericum curvisepalum (Nomenclature)
Shrub 0.3-1.2 m tall, with branches spreading to pendulous. Stems yellow-brown (young parts purplish at first), 4-lined when young, soon terete, slender, internodes 10-25 mm long, shorter than leaves; bark grey-brown. Leaves petiolate, with petiole 0.5-1 mm long; lamina 20-40 x 8-20 mm, triangular-lanceolate to triangular-ovate, acute or more rarely obtuse to rounded, margin plane, base rounded to shallowly cordate, ± glaucous beneath, chartaceous; venation: 3-4 pairs main laterals, branched, the midrib pinnately branched, with tertiary reticulum obscure or invisible; laminar glands streaks (occasionally elongate) and dots. Inflorescence 1(3)- flowered, from apical node; pedicels 6-10 mm long; bracts linear or usually foliar. Flowers 20-40 mm in diam., deeply cyathiform; buds ovoid, acute to apiculate. Sepals 8-14 x 3-5 mm, free, imbricate, unequal, outcurved or spreading and purplish in bud and fruit, ovate to lanceolate or narrowly elliptic or rarely foliaceous, subacute to acuminate or rarely apiculate-obtuse, margin entire, midrib narrow sometimes indistinct; laminar glands linear, interrupted distally. Petals deep yellow, markedly incurved, 12-22 x 8-17 mm, 1.1-1.5(-2) x sepals, broadly obovate to subcircular, with apiculus subterminal, obtuse to rounded; margin entire, eglandular. Stamen fascicles each with c. 60 stamens, longest 10-12 mm long, 0.35-0.7 x petals; anthers deep (?) yellow. Ovary 6-8 x 4.5-6 mm, ± broadly ovoid; styles 3-4 mm long, c. 0.5 x ovary, free, outcurved near apex; stigmas narrowly or scarcely capitate. Capsule (12)14-17 x 8-10 mm, ovoid-conic to broadly ovoid, with thickly coriaceous valves, turning cherry red at first. Seeds dark reddish-brown, 0.8-1 mm long, cylindric, not winged, not or scarcely carinate, shallowly linear-foveolate.
Dry or rocky hillsides and open woodland; 1800-3000 m.
China (north Yunnan, south Sichuan, west Guizhou).
H. curvisepalum is clearly derived from H. lancasteri, which has shorter styles than H. stellatum and sometimes 1-flowered inflorescences. In general, however, H. curvisepalum has smaller, more deeply cup-shaped, nodding flowers with relatively shorter stamens and styles; and it is usually more slender and delicate except for the fruits which, although smaller, tend to be rather massive. Its leaves tend to be shorter and broader and have a shorter petiole and longer translucent glandular streaks. I was reluctant, at first, to describe two closely related species with such overlapping distributions; but the above differences seem to be constant. It seems possible, therefore, that H. lancasteri gave rise to H. curvisepalum by 'trend variation' and subsequent isolation, and that the present syntopy of these taxa is secondary.