Hypericum pycnophyllum (Nomenclature)
Shrub 0.2-1 m tall, erect, with branches very strict, pseudo-dichotomous and lateral. Stems reddish-brown, 2-lined and compressed when young, the subfoliar ridges broad, very soon terete, appearing articulated when old, cortex exfoliating at first in strips between subfoliar ridges; internodes 1-1.5 mm long. Leaves petiolate with short petiole (c. 0.5 mm long), densely imbricate, markedly tetrastichous, deciduous above petiole without fading or with attached cortex below after fading; lamina 3-9 x 0.5-2 mm, very narrowly elliptic to linear, incurved to canaliculate, ± cucullate, midrib impressed beneath, margin narrowly hyaline, dull above, lucent beneath, not glaucous, coriaceous; apex acute, base angustate to above 'articulation' then broadening, pairs forming narrow interfoliar ridge; basal vein 1, unbranched; laminar glands dense, obscure, visible above only. Inflorescence 1-flowered, terminal and on lateral branches, sometimes with single or pseudo-dichotomous branches from node below; pedicel absent or up to 3 mm long, not or slightly incrassate upwards; upper leaves not transitional. Flowers 10-20 mm in diam., stellate to obconic. Sepals 5-6(-7) x 1-2 mm, subequal, lanceolate to oblong-lanceolate, acute to acuminate, cucullate, with margin narrowly hyaline; veins 3-7, unbranched, midrib not prominent; glands linear, uninterrupted. Petals deep? yellow to orange-yellow, 7-14 x 3.5-7 mm, c. 1.6 x sepals, oblanceolate; apiculus acute; glands linear, distally interrupted. Stamens 55, longest 4.5-6.5 mm long, c. 0.6 x petals. Ovary c. 2 x 1 mm, ovoid; styles 3, 3.5-4 mm long, 1.5-2 x ovary, diverging-incurved; stigmas subclavate. Capsule 5-7 x 2.5-3 mm, narrowly ovoid, shorter than sepals. Seeds c. 1 mm long, ecarinate; testa finely ribbed-scalariform.
In open Pinus occidentalis forest and among rocks at higher altitudes; 1700-3175 m.
Dominican Repubhc (Santiago, La Vega, San Juan, Azua).
The specimens from higher altitudes have shorter leaves. Hypericum pycnophyllum is apparently more widespread than H. ekmanii and links it morphologically with H. millefolium.