Hypericum calycinum (Nomenclature)
Shrub 0-2-0-6 m tall, evergreen, with creeping branching stolons and erect, usually unbranched stems. Stems brownish-orange to red, 4-lined, ancipitous when young; internodes 20-60 mm long, shorter than leaves; bark grey. Leaves subsessile or with petiole up to 2 mm long; lamina 45-95(-104) x 15-39(^5) mm, oblong to elliptic or ± narrowly ovate, obtuse to apiculate, margin plane, base cuneate to rounded, paler beneath, not glaucous, coriaceous, lower ones eventually deciduous; venation: 3-4 pairs main laterals, not clearly distinct from midrib branches, with tertiary reticulum dense, conspicuous especially beneath; laminar glands very short streaks or dots in the reticular areolae; ventral glands absent. Inflorescence l(2-3)-flowered; pedicels absent or 10-12 mm long; bracts small, lanceolate, persistent. Flowers 50-80(-95) mm in diam., stellate; buds broadly ovoid to globose, rounded. Sepals 10-20 x 7-15 mm, free, imbricate, markedly unequal, erect in bud, ± ascending in fruit, broadly elliptic to subcircular or obovate, ± cucullate, margin entire or minutely and remotely denticulate, midrib not distinct, veins not prominent; laminar glands linear, distally dissected, numerous. Petals bright yellow, not tinged red, spreading, 25-40 x 13-22 mm, 2-2.5 x sepals, obovate to oblanceolate, with apiculus lateral, rounded, margin entire or minutely and remotely denticulate, eglandular. Stamen fascicles each with 90-120 stamens, longest 20-30 mm long, c. 0-75 x petals; anthers red or rarely bright yellow. Ovary 5-9 x 3.5-6.5 mm, ovoid to ovoid-conic; styles (5 or rarely 4) 12-20 mm long, 1.5-3 x ovary, free, erect or spreading; stigmas small. Capsule 10-20 x 10-13 mm, ovoid to ovoid-conic or rarely narrowly ovoid-cylindric. Seeds reddish-brown, 1-5-2 mm long, cylindric, not or narrowly carinate, shallowly linear-reticulate to -foveolate.
2n = 20.
In shady woods (especially Quercus and Fagus) and on dry or damp shaded banks; 30-1200 m.
Bulgaria (south-east), Turkey (north, along the Black Sea eastward to Trabzon). Widely cultivated and often naturalised. Records from west Transcaucasia (e.g. by Ledebour, Boissier and Gorshkova) are apparently based on introductions.
All material of this species hitherto examined has had red anthers, the leaves have been mostly oblong or elliptic-oblong, and the capsule ovoid to ovoid-conical. Plants grown from a seed collection made in Turkey (Bolu Prov.) by Mark Flanagan (TURX 119), however, have proved to be rather different. The plants in our Limpsfield garden all have yellow anthers, the leaves are narrowly elliptic to elliptic-oblong, and the capsule narrowly ovoid-conical. Plants from the same seed collection grown at Wakehurst Place are morphologically similar, but the anthers are the typical red. A detailed study of variability in H. calycinum may lead to the conclusion that the small differences in this population merit recognition at species or subspecies level; but, until one such study is made, it seems desirable to recognise these small differences at a lower rank.