Hypericum heterophyllum (Nomenclature)
Shrublet (0.05)0.1-0.2(0.3) m tall, much branched to form flattish-topped bush, with basal lignified parts branched effectively pseudo-dichotomously, with branches erect and straight to decumbent and twisted; wholly glabrous, without dark glands. Stems 2-lined at first with short internodes and bearing small scale-like leaves, later 2-lined to terete with elongate internodes, the latter (inflorescence-bearing) part obscurely glandular and withering and leaving the over-wintering basal part bearing pairs of strobiliform condensed shoots; cortex green; bark smooth, reddish brown to greyish brown. Leaves free, sessile; perennating scale-leaves 0.5- 1.5 mm long, broadly ovate or orbicular to obovate, cucullate, obtuse, apiculate to muticous, (all?) elongating in spring to spathulate, glaucous above, soon deciduous; foliage leaves 5-15 x 1-2 mm, narrowly elliptic-oblong to linear, concolorous, thinly glaucous above at least when young, coriaceous, apex acute, margin plane, base cuneate. Inflorescence (l-)3-5-flowered, terminal and often with single flowers or 3-5-flowered cymules in axils of 1-2 lower nodes, the whole up to 13-flowered, rounded-pyramidal to subcorymbiform; bracteoles triangular-lanceolate to linear; pedicels very short or absent. Flowers 8-12 mm in diam.; buds ellipsoid, subacute. Sepals green, 2-3.5 x 0.8-1.2 mm, imbricate, unequal, oblong to ovate-lanceolate, acute to subacute, entire; veins 5(3), not or only midrib prominent, unbranched; laminar glands linear to striiform. Petals bright yellow, not tinged red, 5-8 x 2.5-3 mm, 2.2- 2.5 x sepals, obovate to oblanceolate, obtuse to rounded with apiculus small, subterminal or obsolete, with laminar glands linear. Stamens 35-45, longest 4.5-7 mm, c. 0.9 x petals. Ovary c. 1 .5 x 0.7 mm, cylindric-ellipsoid to narrowly ovoid-cylindric, truncate; styles c. 4 mm long, c. 2.4 x ovary, widely spreading. Capsule 6-8 x 3-3.5 mm, ovoid-cylindric to narrowly cylindric, chartaceous, surrounded by old petals, longer than sepals, with valves longitudinally vittate. Seeds 2 on each placenta, not seen mature, rather prominently carinate; testa foveolate.
2n = 18 (Reynaud, 1973).
Dry clearings in Pinus nigra subsp. pallasiana (Lamb.) Holmboe woodland and in garigue with Cistus laurifolius L.; 1200-2000 m.
Turkey (north-west and west-central Anatolia).
H. heterophyllum is systematically isolated in Hypericum. It seems to share with H. aegypticum (sect. 25) an origin near H. balfourii or H. socotranum (sect. 1) but to be neither wholly apomorphic nor wholly plesiomorphic in relation to it. It lacks the specialisations that, in Hypericum, are unique to sect. 25. Adenotrias, viz. the heterostyly syndrome and the carunculate seeds; but it is more specialised than H. aegypticum in habit, in its biovulate placentae and in its chromosome number (2n = 18), whereas H. aegypticum and H. russeggeri, both sect. 25, have 2n = 20).
A detailed account of the growth form and behaviour of H. heterophyllum, both in nature and in cultivation, has been given by Hagemann (1989). For its relationship with H. aegypticum see p. xx.
Neither Boissier (1867) nor Stefanoff (1931-1934) seems to have doubted Ventenat's attribution of this species to the Iranian flora, despite the absence of subsequent collections from that country. Stefanoff (1931) drew attention to the collection by Whittall (K) labelled 'Smyrna', but correctly treated this locality as Whittall's address. Later (1933a: 145, 1933b), he accepted the Smyrna label for want of a more accurate locality. More recent collections have revealed the real native region of H. heterophyllum to be north-western and west-central Turkey, from Balikesir and Afyon to Ankara and Ҫankiri, a region traversed by Olivier and Bruguière on their journey to and from Iran in 1797-98.