Herbs , annual, biennial, or perennial, caulescent, from taproots, tubers, or rhizomes. Stems erect to prostrate, simple or branching. Leaves basal and/or cauline, simple or usually compound; blade with 2-6 orders of leaflets and/or lobes. Inflorescences axillary or terminal, paniculate or racemose, multifloral, sometimes cleistogamous-flowered (in Corydalis flavula , occasionally C . micrantha ). Flowers bilaterally symmetric about 1 plane; sepals caducous or persistent; petals distinct or somewhat coherent basally, not spongy; outer petals dissimilar, each with median adaxial keel or crest, sometimes with distal marginal wing, 1 basally spurred, the other sometimes gibbous but not spurred; inner petals connate apically; stamens with nectariferous spur projecting from near base of median filament in bundle opposite spurred petal and adhering to inner surface of petal spur; ovary broadly ovoid to obovoid; stigma persistent, with or without 2 lobes or apical horns, or 4-8 papillar stigmatic surfaces. Capsules dehiscent, 2-valved. Seeds few-many, reniform to subglobose, elaiosome usually present. x = 8. Several native species of Corydalis have been grown as ornamentals, particularly C . scouleri , C . aurea , C . sempervirens , and C . caseana ; they may be found as garden escapes in areas of the continent outside their natural ranges. Two Eurasian species that are widely cultivated in the flora area also escape sometimes, but evidently they are not truly naturalized here. Corydalis lutea (Linneaus) de Candolle, reported from New York and Oregon, can be distinguished from the native species that also are rhizomatous perennials by its yellow petals and axillary racemes. Corydalis solida (Linneaus) Swartz (sometimes identified as C . bulbosa Persoon), reported from Connecticut, Massachusetts, Vermont, and southern Ontario, can be distinguished from the native species that also are tuberous perennials by its lack of sepals, pedicels usually longer than 10 mm, and sometimes yellow petals.
PLANT: Erect or prostrate herbs. STEMS: simple or branching from taproots. LEAVES: once or twice compound. INFLORESCENCE: terminal or axillary racemes or panicles. FLOWERS: showy; sepals elliptic, attached at base, attenuate, yellow to white; petals yellow when fresh, drying yellow to cream, with or without purplish discoloration; style persistent. FRUITS: cylindrical, capsules constricted between seeds. SEEDS: few to many, black, with aril. NOTES: Ca. 100 spp., 1 in AZ. Temperate N. Amer., Eurasia, Africa. (Greek: Korydallis = Crested Lark). Stern. K. R. 1997. Corydalis. Pp. 348-355 in N. R. Morin (ed.), Flora of North America, vol. 3, Oxford University Press, New York. REFERENCES: Holiay, Susan, and Abril Perez. 2001. Commelinaceae. J. Ariz. - Nev. Acad. Sci. Volume 33(1).