Hypericum senkakuinsulare (Nomenclature)
Shrub c. 0.6 m tall, with branches spreading. Stems soon terete; internodes 10-20 mm long, shorter than leaves; bark reddish-brown. Leaves sessile; lamina 23-35 x 10-18 mm, elliptic or oblong-elliptic to obovate, rounded, margin plane, base cuneate to cuneate-angustate, not glaucous, chartaceous, deciduous; venation: 1 pair main laterals (intramarginal) and c. 5-6 pinnate midrib branches, without visible tertiary reticulum; laminar gland dots numerous; intramarginal glands. Inflorescence 1-flowered, terminal, without subsidiary branches; pedicels c. 10 mm long; bracteoles elliptic. Flowers c. 40 mm in diam., cyathiform; buds narrowly ovoid, subacute. Sepals c. 3 x 2 mm, very slightly connate ?, not or scarcely imbricate, subequal, erect in bud, broadly oblong, obtuse; laminar glands linear. Petals bright yellow, not veined or tinged red, incurving, c. 25 x 18 mm, c. 6 x sepals, obovate, very short, apiculus rounded. Stamen fascicle seach with c. 15 stamens, longest c. 15 mm long, c. 0.7 x petals. Ovary with styles 9 mm long, slender. Capsule c. 10 mm long, narrowly ovoid. Seeds not recorded.
Near rocky summit of mountain; 360 m.
Ryukyu Islands (Senkaku Group).
H. senkakuinsulare is known from only the type locality. It is apparently related to H. formosanum, the geographically nearest species, but differs in its consistently rounded leaves, its solitary cyathiform flowers with smaller sepals, and (?) its narrower capsules.