Hypericum erectum var. erectum angustifolium (Nomenclature)
Diagnostic description:
Stems 0.3–0.7 m tall, solitary, erect. Leaves c. 35 × 8–10 mm, lanceolate to linear-oblong, apex obtuse to rounded; laminar and intramarginal glands black. Sepals c. 4 mm long, elliptic-oblong, laminar and intramarginal glands black, punctiform. Petals c. 7 mm long, nigro-punctate or shortly nigro-striate. Ovary c. 3.5 mm long; styles 3 mm. Capsule 7 × 4 mm, ovoid-ellipsoid. Seeds not seen.
Distribution:
Japan (Honshū–Fukushima westward to Yamaguchi, Kyūshū–Miyazaki).
Notes:
Smaller than f. erectum with narrower leaves. This taxon may not be monophyletic.