Hypericum yamamotoi Miyabe & Kimura

Perennial herb c. 0.5 m long, suberect to ascending or procumbent from woody base, with stems usually solitary, unbranched below inflorescence. Stems narrowly 2-lined at first, sometimes soon terete, eglandular; internodes 15–55 mm, equalling or exceeding leaves. Leaves sessile; lamina 35–50 × 15–20 mm, narrowly oblong to lanceolate, paler beneath, chartaceous; apex rounded to subapiculate-obtuse, margin plane, base rounded to subcordate-amplexicaul; venation: 3–4 pairs of main laterals from lower fifth to 2/5 of midrib and sometimes base; tertiary reticulation dense, visible on both sides; laminar glands black, scattered and sometimes pale, few, especially in upper leaves, all punctiform; intramarginal glands black, dense. Inflorescence 5–15-flowered, from 3 nodes, lax, with branches from 2 nodes below, the whole broadly pyramidal; pedicels 2–3.5 mm, slender; bracts reduced-foliar, bracteoles linear-lanceolate. Flowers c. 20 mm in diam., stellate; buds ellipsoid, rounded to subobtuse. Sepals 5, unequal, 3.5–5.5 × 1–1.5 mm, linear-oblong to linear-lanceolate, subacute to acute, entire; venation: 5, outer sometimes branching and anastomosing; laminar glands pale, striiform to punctiform; marginal glands black, few (1–4) or absent. Petals 5, bright? yellow, not tinged red, 10–12 × c. 2.8 mm, 2–3 × sepals, narrowly oblanceolate, rounded, entire; laminar glands pale, linear; marginal glands absent. Stamens c. 35, ‘3’-fascicled, longest 10–11 mm, c. 0.9 × petals; anther gland black. Ovary 3.5–4 × 1.5 mm, ellipsoid; styles 3, free, widely incurving, 6 mm, c. 1.5 × ovary; stigmas narrow. Capsule and seeds not seen.