Prunella asiatica var. albiflora (Koidzumi) Nakai; P. vulgaris Linnaeus var. albiflora Koidzumi.

Stems purple-red, numerous, ascending, 20-60 cm, pilose especially toward apex. Petiole 1-2 cm; leaf blade ovate to ovate-oblong, 3-4.5 × 1-1.5 cm, adaxially appressed puberulent or subglabrous, abaxially sparsely pilose on veins, base cuneate to attenuate, margin slightly undulate or crenate-serrate, apex obtuse to acute. Spikes terminal, 3-5 cm, sessile; floral leaves subsessile or short petiolate, broadly lanceolate; bracts tinged red, reduced at apex, oblate, 5-8 × 6-8 mm, caudate, veins pilose. Pedicel ca. 2 mm. Calyx ca. 1 cm, apex red or purple, white villous, tube ca. 4 mm, turbinate; upper lip subcircular, ca. 6 mm wide, truncate; lower lip narrower, ca. 3.5 mm, teeth lanceolate, spiny. Corolla purplish or dark purple to white, 1.8-2.1 cm, glabrous; tube ca. 1 cm, abruptly dilated beyond middle; upper lip oblong, ca. 9 × 6 mm, concave, keeled; lower lip ca. 8 × 9 mm, middle lobe subcircular, fringed; lateral lobes oblong, small, pendulous. Anterior stamens very long. Nutlets ovoid, ca. 1.5 × 1 mm, apex rounded, glabrous. Fl. May-Jul, fr. Aug-Sep.

Used as a diuretic.

Grassy slopes, wet areas, thickets; 0-1700 m. Anhui, Heilong-jiang, Jiangsu, Jiangxi, Jilin, Liaoning, Shandong, Shanxi, Zhejiang [Japan, Korea]