6. Leonurus macranthus Maximowicz, Prim. Fl. Amur. 9: 476. 1859.
大花益母草 da hua yi mu cao
Plants perennial. Rhizomes woody. Stem erect, 60-120 cm, solitary, appressed retrorse strigose. Petiole of basal leaves ca. 2 cm; lower stem leaf blades cordate-orbicular, 7-12 × 6-9 cm, 3-lobed, sparsely minutely hispid, base cordate, margin incised, apex acute; mid stem leaves ovate. Verticillasters sessile, 8-12-flowered; floral leaves reduced, ovate to ovate-lanceolate, margin irregularly incised to subentire, apex long acuminate; bracteoles spiny, ca. 7 cm, hispid. Flowers subsessile. Calyx tubular-campanulate, 7-9 mm, strigose, with spinescent teeth, veins conspicuously elevated; anterior teeth subulate-triangular, ca. 1 cm; posterior teeth triangular, ca. 5 mm. Corolla reddish or reddish purple, 2.5-2.8 cm, densely pubescent, scaly annulate inside, scaly near lower lip; tube gradually dilated at apex, ca. 1/2 as long as corolla; upper lip straight, oblong, concave, ca. 12 × 5 mm, margin entire; lower lip ca. 8 × 5 mm, middle lobe ca. 2 × as long as ovate lateral lobes, obcordate, conspicuously emarginate. Nutlets black-brown, oblong, triquetrous, ca. 2.5 mm, base cuneate, apex truncate. Fl. Jul-Sep, fr. Sep.
Grassy slopes, thickets; 0-400 m. Hebei, Jilin, Liaoning [Japan, Russia].