Hypericum acmosepalum (Nomenclature)
Shrub 0-6-2 m tall, with branches erect to ascending. Stems orange, 4-angled and ancipitous in first year (or longer), then terete; internodes 10-50 mm long, shorter than to exceeding leaves; bark grey-brown. Leaves broadly petiolate, with petiole 0.5-1(1.5) mm, long; lamina 18-42(-60) x 6-15(-20) mm, oblong or elliptic-oblong to narrowly elliptic (sometimes lanceolate towards apex ef shoot and oblanceolate towards base), obtuse (rarely subacute) or apiculate to rounded, margin plane, ± recurved, base cuneate, markedly paler to glaucous beneath, chartaceous to subcoriaceous; venation: 1-2 pairs main laterals (the upper forming distinct, often ± straight intramarginal vein), with midrib rather obscurely branched distally, with rather dense but very obscure or invisible tertiary reticulum; laminar glands ± small dots and sometimes short streaks, ventral glands sparse to rather dense. Inflorescence l-3(-6)-flowered, from apical node, subcorymbiform; pedicels 7-17 mm long; bracts foliar to lanceolate, persistent. Flowers 30-50 mm in diam., stellate; buds ovoid, acute to subapiculate. Sepals (5-)6-9(-11) x 3-4(-6) mm, free, imbricate, subequal, ± outcurved in bud and fruit, ovate to narrowly lanceolate, acute or acuminate, with margin subentire or minutely and ± irregularly denticulate (especially towards apex); midrib ± conspicuous, veins not prominent; laminar glands linear or interrupted, c. 8. Petals deep yellow, sometimes tinged red, spreading or reflexed, 16-25 x 10-15 mm, 2.5-3 x sepals, obovate, with apiculus lateral, subacute to obtuse, margin entire or often minutely glandular-denticulate especially around apiculus. Stamen fascicles each with 40-65 stamens, longest (10)15-18 mm, long, 0.75-0.85 x petals; anthers yellow to orange-yellow. Ovary 5-7 x 3.5-4.5 mm, ± narrowly ovoid-conic; styles (3-)4-6(-8) mm, long, equalling to slightly longer than ovary, free, suberect, outcurved near apex; stigmas truncate to narrowly subcapitate. Capsule 9-15 x 8-10 mm, ovoid to narrowly ovoid-conic, turning bright red during maturation. Seeds dark orange-brown to reddish-brown, 1-1.1 mm long, narrowly cylindric, narrowly carinate with terminal expansion, shallowly linear-foveolate.
Forest glades, roadside banks, hillsides among scrub, open stream-sides; 900- 3000 m.
China (N. and E. Yunnan, S. Sichuan, NW. and NE. Guizhou, Guangxi).
H. acmosepalum, along with H. fanjingense and H. pseudohenryi, appears to form a clade that (like the H. patulum clade) is directly related to H. siamense. Its stellate flowers with long stamens and styles and acute sepals, and its bright red young fruits, are reminiscent of H. kouytchense; but its erect habit, elliptic to oblong leaves with a marked intramarginal vein, and deep yellow petals are quite distinct and make it easily distinguishable.