Hypericum ludlowii (Nomenclature)
Perennial herb up to 0.4 m tall or long, erect or ascending from creeping and rooting base, with stems slender, growing through other vegetation, unbranched or with short branches from upper or occasionally several nodes. Stems 2-4-lined, eglandular; internodes 7-30 mm, exceeding leaves. Leaves petiolate, with petiole 0.5-1 mm; lamina 3-20 ´ 1.5-10 mm, triangular-ovate or elliptic to oblong-oblanceolate, paler beneath, not glaucous, subchartaceous; apex rounded, margin entire, plane, base rounded to rarely cuneate; venation: 3(2) pairs of main laterals from lower third to quarter of midrib, with tertiary reticulation dense; laminar glands pale, punctiform, very small, dense to sparse; intramarginal glands all black or black and pale or reddish, rather dense. Inflorescence 1-9-flowered from 1-2 nodes, subcorymbose or broadly pyramidal to cylindric or bifurcate, sometimes with flowering branches from up to 3 nodes below; pedicels 1.5-3 mm; bracts and bracteoles narrowly oblong and black- or red-glandular-ciliate and -auriculate or reduced-foliar and entire without auricles, persistent. Flowers (6-)9-11(-15) mm in diam., stellate; buds cylindric-ellipsoid, subacute. Sepals 5, subequal or unequal, 1.5-5 ´ 0.5-1.5 mm, erect in bud and fruit, narrowly oblong or narrowly elliptic to lanceolate, obtuse to acute, glandular-ciliate to entire; veins 5, unbranched; laminar glands linear, all pale or partly black; marginal glands black or reddish, on cilia or sessile or submarginal, sometimes few. Petals 5, golden yellow, not tinged red in bud, 4-7 ´ 1-2.5 mm, (1.3-)1.5 ´ sepals, oblong-oblanceolate, rounded, margin with black or reddish gland in apiculus and sometimes a few subapical sessile black glands, without or rarely with 1-2 laminar black streaks. Stamens c. 20, '3'-fascicled, longest 4-5 mm, c. 0.6-1 ´ petals; anther gland black. Ovary 3?-locular, 1.6-2.5 ´ 1-2 mm, ellipsoid to subglobose; styles 3, 2-2.5 mm, 1-1.4 ´ ovary; stigmas narrowly to scarcely capitate. Capsule 4.5-6 ´ 2.5-3.5 mm, cylindric-ellipsoid to ellipsoid-subglobose; valves longitudinally vittate. Seeds straw-coloured, 0.4 mm, cylindric; testa foveolate-scalariform.
Grassy swamps, streambanks and bogs; 2850-3400(-3600) m.
China (Yunnan, Xizang), Bhutan.
H. ludlowii shows a reduction trend westward from Yunnan to Bhutan. The easternmost populations are rather similar to the 'intermediate' population of H. himalaicum in N. Burma and adjacent India, but differ in the smaller overall size and delicate habit and in the size of the leaves and floral parts, as well as in the absence, in the more reduced forms, of black glands (except in the anthers). The upper leaves in this easternmost population, however, are 'trigonous' as in typical H. trigonum. From H. himalaicum it differs in the relatively longer styles and narrower acute sepals that are not black-streaked, and it is usually distinct in the smaller flowers, shorter ascending stems and boggy habitat. The styles are not absolutely longer, but the smaller ovary makes them relatively so. It would therefore appear probable, for morphological as well as geographical reasons, that H. ludlowii is related directly to H. trigonum, not via the H. himalaicum 'intermediate' population..