巨紫堇 ju zi jin

Corydalis curvicalcarata Miyabe & Kudô; C. gigantea var. amurensis Regel; C. gigantea var. macrantha Regel; C. macrantha (Regel) Popov; C. zeaensis Michajlova.

Herbs, perennial, 50-120 cm tall. Young rootstock with single head, 2-3 × 1-1.2 cm, thickened when old with 2 or 3 heads and few fibrous roots. Stems pale brown, shiny, hollow, ca. 1 cm in diam., naked below, leafy and sparingly branched above. Radical leaves 2-4 × ternate to pinnate. Cauline leaves glaucous abaxially, dark green adaxially, biternate to pinnate; ultimate leaflets unequally deeply 2- or 3-divided; segments lanceolate, 3-7 × 1.5-3 cm. Racemes simple or sparingly branched at base, densely 10-20(-50?)-flowered; axillary inflorescence smaller; bracts linear, usually shorter than 3-6 mm erect pedicels, or lowermost bract(s) much larger. Sepals early falling, ovate to oblong, 4-10 × 2-4 mm, entire, acute. Flowers nutant, purplish red to almost red. Upper petal 3-4 cm, apex acute, ± curved; spur straight (upcurved in bud), broad, slightly narrowed toward obtuse apex, 20-27 mm, ca. 2 × as long as limb or more; nectary extended through ca. 2/3 of spur; lower petal navicular, 11-12 mm; inner petals 9-10 mm. Stigma oblong, upper part with 4 papillae, base with 2 papillae. Capsule obovoid, 7-9 × 3-4 mm, explosively dehiscent; style ca. 4 mm. Seeds angular, ca. 3 mm, smooth, with small elaiosome. Fl. Jun-Aug.

Understories of deciduous and broad-leaved Pinus koraiensis mixed forests, ditch sides. Heilongjiang (Dailing, along Heilong Jiang, Yichun), SE Jilin (Linjiang) [Japan (Hokkaido), N Korea, Russia (Far East)].

In FRPS (32: 157. 1999), this species was treated as Corydalis macrantha. That name is a synonym of C. gigantea here, whereas the plant described as C. gigantea in FRPS (loc. cit.: 159) seems to be referable to the closely related species C. multiflora Michajlova (Novosti Sist. Vyssh. Rast. 19: 100. 1982), which does not occur in China but was previously called C. gigantea in Russian floras.