Perennial herb, 0.05–0.33 m tall, glabrous, erect or ascending from creeping, rooting and branching base, sometimes mat-forming, usually with short axillary shoots from all nodes below inflorescence. Stem 2-lined, green or red, eglandular; internodes 5–35 mm, equalling or usually exceeding leaves. Leaves up to 0.5 mm petiolate, paler beneath, not or scarcely glaucous, 5–18 ×1–8 mm, oblong-elliptic to narrowly oblong or linear or very narrowly oblanceolate, apex subapiculate to rounded, margin plane to revolute, base rounded to narrowly cuneate or attenuate, with 2–4 pairs of ascending lateral veins; laminar glands pale, punctiform, uniformly dense or sparser towards base, medium-sized; intramarginal glands pale, small, spaced; leaves on axillary shoots smaller. Inflorescence 5-c. 40-flowered, from 2–5 nodes, narrowly cylindric to spiciform, dense or interrupted, 15–110 mm long, with lateral cymules 1–5-flowered, without or with 1–2 pairs of flowering branches below, then making the whole very narrowly pyramidal; bracts and bracteoles narrowly oblong to linear, entire. Flowers 10–20 mm in diam., petals erect after flowering; buds cylindric to subglobose, rounded. Sepals subequal to equal, basally united, not or slightly imbricate, 2–5 × 1.2–2 mm, oblong, obtuse or apiculate to rounded; veins 5, not branching, not prominent; margin entire or with obconic sessile black glands towards apex only; laminar glands pale, linear to striiform. Petals pale yellow, tinged red, 5–12 × 3–6 mm, c. 2.5 × sepals, narrowly oblanceolate; marginal glands black, distal (apical and outer margin), rather large, sessile and on cilia; laminar glands pale, linear to striiform. Stamens 35–40, longest 8– 10 mm; filaments yellow. Ovary 2–3 × 1–1.5 mm, narrowly ellipsoid to narrowly ovoid; styles 4–6 mm, c. 2 × ovary. Capsule 5–6 × 2.5–3.5 mm, narrowly ovoid. Seeds not seen; testa densely papillose.
2n = 18 (Contandriopoulos & Lanzalavi, 1968; Strid & Andersson, 1985; both subsp. alpestre).
Montane grassland, rocky slopes, open woodland; 1200–c. 3000 m.
West and south Transcaucasia, north Iran, north Turkey, Russia (Ciscaucasia), Krym, northern Greece (Makedhonia), Bulgaria, southern Serbia.
Hypericum linarioides and H. pseudorepens are basal to the clade that comprises the larger part of sect. Taeniocarpium, being inter alia the only species in the clade to have entire sepals (except 27. taygeteum and 28. saxifragum, in which the lack of glands is derived); but they are specialised in their creeping habit.
The nearest form of H. linarioides to H. pseudorepens is the broad-leaved tall form in Georgia known as H. polygonifolium. From it, two reduction trends can be traced. In one, which extends westward through northern Turkey to Bursa (Uludağ), the broad leaves are gradually narrowed from oblong or elliptic-oblong to linear without any obvious ‘gap’ in the trend. In the other, which runs to the north of the Black Sea first to the Crimea and then, with another gap, to Bulgaria, northern Greece and Serbia, the gradual change is from oblong to oblanceolate then linear, i.e. the broadest part of the leaf moves towards the apex. The first population has been known as H. repens sensu Jaub. & Spach non L., H. polygonifolium Rupr. and (correctly) H. linarioides Bosse, the second as H. alpestre Steven. However, since some Georgian plants display a tendency for the leaves to be broadest above the middle, it seems best to treat the two populations as subspecies.
Another population, from Kars and Erzerum in north-eastern Turkey, was distinguished as H. perplexum subsp. karsianum by Woronow (1909) and given specific rank by Grossheim (1932). As I remarked in the Flora of Turkey (Robson, 1967), the syndrome of characters in this population (leaves linear to linear-oblong, inflorescence a ‘thyrsoid racemiform panicle’and sepals relatively short compared to the petals and with a short glandular or eglandular acumen) gives it a distinct appearance but is not sufficient to distinguish it taxonomically.