Hypericum x hyugamontanum Y. Kimura

Perennial herb 0.05–0.3 m tall, erect to ascending, with stems caespitose, simple or branched. Stems obscurely 2-lined, eglandular; internodes 9–13 mm, shorter than leaves. Leaves sessile; lamina 8–40 × 3–13 mm, oblanceolate to linear-oblanceolate, paler beneath, thinly chartaceous; apex rounded to obtuse, margin plane, base slightly attenuate; venation: 3 pairs of laterals, from lower quarter to 2/5 of midrib, tertiary reticulation lax, obscure?; laminar glands pale, punctiform, dense; intramarginal glands black, irregular. Inflorescence 3-10-flowered, from 2 nodes, without branches below, subcorymbiform; pedicels 3.5–4 mm; bracts and bracteoles foliar, lanceolate to narrowly elliptic. Flowers 7–13 mm in diam., concave?; buds ellipsoid, rounded? Sepals 5, unequal, c. 3–4 × 1–1.6 mm, oblong to ovate-oblong, rounded to obtuse, with c. 3–6 glandular cilia on at least 2/3 of sepals on a plant; veins 5, unbranched; laminar glands pale, linear; marginal glands black, on cilia or sometimes sessile. Petals 5, mid? yellow, not tinged red, 6–8 × 3 mm, 2–2.2 × sepals, oblong-oblanceolate, with prominent glands; laminar glands pale, linear to striiform; marginal glands black, prominent. Stamens 25–50, ‘3’-fascicled, longest 7–8 mm, slightly shorter than petals; anther gland black. Ovary c. 3 × 1.2 mm, ovoid-cylindric; styles 3, free, divergent, 1.3–3 mm, 0.5–1 × ovary; stigmas narrow? Capsule 4.5–7.5 × 2.7–4.5 mm (l : b = 1.4–2.2), 1.5–1.85 × sepals, ovoid-conic. Seeds not described.