26. Rumex amurensis F. Schmidt ex Maximowicz, Prim. Fl. Amur. 228. 1859.
黑龙酸模 hei long suan mo
Herbs annual. Stems erect, 10-30 cm tall, branched from base, glabrous. Lower leaves: petiole 1-2.5 cm, slender; leaf blade oblanceolate or narrowly oblong, 2-7 × 0.3-1.2 cm, both surfaces glabrous, midvein conspicuous, base narrowly cuneate, margin slightly crisped, apex obtuse or acute; cauline leaves with short 2-5 mm petiole, leaf blade linear-lanceolate; ocrea fugacious, membranous. Inflorescence racemose, several racemes aggregated and panicle-like, leafy. Flowers bisexual. Pedicel articulate at base. Outer tepals elliptic, smaller; inner tepals enlarged in fruit; valves triangular-ovate, all with tubercles; only 1 valve with 2 pairs of narrow teeth; teeth 3.5-4 mm, straight or slightly curved at apex, other valves shortly denticulate. Achenes brownish, shiny, ellipsoid, sharply trigonous, ca. 1.5 mm, base narrow, apex acute. Fl. May-Jun, fr. Jun-Jul.
Streamsides, ditches, wet areas; sea level to 300 m. Anhui, Hebei, Heilongjiang, Henan, Hubei, Jiangsu, Jilin, Liaoning, Shandong [Russia (Far East)].