Species in the genus Isodon:

Isodon inflexus / Yamahakka
Isodon inflexus f. leucanthu / Shirobanayamahakka
Isodon japonicus / Hikiokoshi
Isodon longitubus / Akichouji
Isodon longitubus f. albiflora / Shirobanaakichouji
Isodon shikokianus var. intermedius / Takakumahikiokoshi
Isodon shikokiana var. occidentalis / San'inhikiokoshi
Isodon shikokiana var. occidentalis f. albiflorus / Shirobanasan'inhikiokoshi
Isodon trichocarpus / Kurobanahikiokoshi
Isodon umbrosus / Inuyamahakka

Isodon shikokiana var. occidentalis / San'inhikiokoshi サンインヒキオコシ

Isodon shikokiana var. occidentalis is a perennial herb in broad-leaved forests like a beech forest. Stems grow to 40-80cm in height, with four ridges. Leaves are of opposite phyllotaxis, with bases cuneate, sharp serrations on margins, coarse hairs on both surfaces, adpressed hairs on upper mid midribs, and erect hairs on lower surfaces' midribs. The flowers are light purple; the corolla's upper lips are cleft in four and bend upward. Bloom time: August-October.