Hypericum maculatum (Nomenclature)
Perennial herb 0.2-0.6 m tall, erect or ascending from creeping and rooting base, with stems numerous to few, initially unbranched below inflorescence, later branched above for c. 2/3 of their length. Stems 4-lined, the subsidiary ones (decurrent between leaves) often less prominent or even partially absent[1], usually with black glands on the lines; internodes 10-50 mm, shorter than to exceeding leaves. Leaves sessile; lamina 15-40 ´ 10-20 mm, broadly to narrowly elliptic, paler beneath, chartaceous; apex rounded, margin plane, base rounded; venation: 3(2) pairs of main laterals from lower quarter to base of midrib, tertiary reticulation dense; laminar glands absent or rarely pale, scattered, sometimes also black, few, punctiform; intramarginal glands black, ± close, irregular in size. Inflorescence (2-)3-c. 15-flowered, from 1-3 nodes, with flowering branches narrowly or curved ascending from up to 5 nodes, the whole cylindric to broadly pyramidal or subcorymbiform; pedicels 1.5-4 mm; bracts and bracteoles up to 5 mm long, narrowly triangular-ovate to narrowly elliptic, entire. Flowers (15-)20-25(-30) mm in diam., stellate to reflexed; buds broadly ellipsoid, rounded to obtuse. Sepals 5, ± unequal, 3.5-4.5(-5) ´ 2-2.7(-3) mm, broadly elliptic to broadly ovate or ± broadly oblong, rounded to obtuse or subacuminate (varying in same flower), entire, erect to recurved in bud, recurved in fruit; veins 5(-7), not or slightly branched; laminar glands pale and sometimes also black, punctiform and sometimes striiform; intramarginal glands pale or occasionally black or often absent. Petals 5, golden yellow, not tinged red in bud, (8-)10-15 ´ 4-7.5 mm, c. 3 ´ sepals, broadly elliptic to obovate or more rarely symmetrically oblanceolate, distally crenate or entire; laminar glands pale and/or black, punctiform and sometimes proximally striiform to linear (in var. immaculatum almost all linear); intramarginal glands few, distal or usually absent. Stamens 50-80(-100), '3'-fascicled, longest 7-10 mm, c. 0.65-0.9 ´ petals; anther gland black. Ovary 3-locular, 2-4 ´ 1.5-2.5 mm, ± broadly ovoid to ovoid-ellipsoid; styles 3, free, 3-4 mm, 1-1.5(-2) ´ ovary, rather narrowly spreadng; stigmas narrowly capitate. Capsule 6-10 ´ 4-6 mm, c. 2-2.5 ´ sepals, ovoid-ellipsoid to ± broadly ovoid; valves with longitudinal vittae, linear to striiform. Seeds dark brown, 0.8-1.2 mm, cylindric, not carinate or appendiculate; testa finely linear-foveolate.
[1]Partial or complete absence of subsidiary lines may possibly indicate hybridisation with H. perforatum (cf. H. ´ desetangsii, p. ).
2n = 16, 32 (see under subspecies).
In usually ± damp habitats - woods, scrub, grassland, moorland, meadows and ditches; 0 (W. Scotland) - 2650 m (SE. Switzerland).
Europe from Scotland (Ross-shire), northern Scandinavia (to Hinnoya (Lofoten Is.), 68°22¢ N), northern European Russia and western Siberia, south to northern Spain, northern Italy, northern Greece and the central Ukraine, and east to south-western Siberia (R. Ob) with eastern outlier near Krasnoyarsk). Introduced into Canada (British Columbia).
H. maculatum is the most primitive species in the (mainly European) Series Hypericum, its nearest relative in the (eastern) Series Senanensia (Spp. 13-19) being 13. H. kamtschaticum var. pibairense from Hokkaido (N. Japan). It comprises two diploid subspecies (subspp. maculatum and immaculatum) and a tetraploid subspecies (subsp. obtusiusculum) that, from chromosome morphology and synthesis by colchicine doubling of subsp. maculatum (Robson, 1958a), would appear to be autotetraploid. The latter has sometimes been treated as a species (H. dubium Leers); but (i) the autotetraploidy and (ii) the occasional difficulty in assigning a plant to one or other taxon indicate that subspecies is the most appropriate rank, pace Mártonfi et al. (1999) (see p. ).
The diploid subspecies of H. maculatum comprise two populations overlapping in distribution. One (subsp. immaculatum) is confined to the south Balkans and lacks black glands on the petals, the pale ones being linear and the leaves usually pale-gland-dotted. Its chromosome number has not yet been counted, but morphologically it is very similar to subsp. maculatum, less so to subsp. obtusiusculum. The other population (subsp. maculatum), which is widespread and slightly overlaps in area that of subsp. immaculatum in a zone from Bosnia to southern Bulgaria, has petals with punctiform to shortly striiform black glands, the pale (punctiform) glands being few, and the leaves usually lack pale gland dots.