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.

Distribution

Temperate North America, Eurasia, and Africa.

Discussion

Species ca. 100 (10 in the flora).

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.

Selected References

Ownbey, G. B. 1947. Monograph of the North American species of Corydalis. Ann. Missouri Bot. Gard. 34: 187-260.

Ownbey, G. B. 1951. On the cytotaxonomy of the genus Corydalis, section Eucorydalis. Amer. Midl. Naturalist 45(1): 164-186.

Ryberg, M. 1955. A taxonomical survey of the genus Corydalis Ventenat, with reference to cultivated species. Acta Hort. Berg. 17(5): 155-175.

Lower Taxa

Corydalis aqua-gelidae, Corydalis aurea, Corydalis caseana, Corydalis crystallina, Corydalis curvisiliqua, Corydalis flavula, Corydalis micrantha, Corydalis pauciflora, Corydalis scouleri, Corydalis sempervirens

Key

1	Plants perennial; petals not yellow; stigma as long as or longer than wide; capsules oblong to obovoid, reflexed.	> 2
1	Plants annual or biennial; petals yellow, or pink tipped yellow; stigma wider than long; capsules narrowly to broadly linear, usually not reflexed.	> 5
2	Roots small, tuberous, usually forked; petals blue, often purple-tinged; stigma rhomboid, narrower toward base; n British Columbia, w Northwest Territories, Yukon, and Alaska.	Corydalis pauciflora
2	Rhizome or roots large and fleshy; petals pink or white; stigma rectangular or triangular, not narrower toward base; w United States and s British Columbia.	> 3
3	Primary inflorescence axis with ca. 15–35 flowers; inner petals not tipped deep red or purple; stigma ± triangular; capsules obovoid; seeds ca. 3.5 mm diam.	Corydalis scouleri
3	Primary inflorescence axis typically with 50 or more flowers; inner petals tipped red or purple; stigma roughly rectangular; capsules usually ellipsoid; seeds 2–2.5 mm diam.	> 4
4	Blades of proximal cauline leaves with ultimate lobes mostly more than 15 mm; spurred petal with marginal wing conspicuous; petals with crest absent or beaklike.	Corydalis caseana
4	Blades of proximal cauline leaves with ultimate lobes 5–15 mm; spurred petal with marginal wing inconspicuous or absent; petals with crest present, wrinkled.	Corydalis aqua-gelidae
5	Petals pink, tipped yellow, crests absent, claws of inner petals distinctly longer than blades; seeds ca. 1 mm diam.	Corydalis sempervirens
5	Petals pale to bright yellow throughout, crests present, claws of inner petals equal to or shorter than blades; seeds 1.5–2 mm diam.	> 6
6	Spurred petal 7–9 mm, spur incurved, ca. 2 mm; capsules pendent, pedicels long.	Corydalis flavula
6	Spurred petal typically 10–22 mm, spur not appreciably incurved, ca. 4–8 mm; capsules erect (or pendent at maturity in Corydalis aurea), pedicels short.	> 7
7	Outer petals with crest conspicuous, marginal wing very broad; capsules usually with basally pustulate whitish hairs.	Corydalis crystallina
7	Outer petals with crest inconspicuous, marginal wing medium to narrow; capsules essentially glabrous.	> 8
8	Plants frequently bearing inconspicuous cleistogamous flowers; seeds ca. 1.5 mm diam.	Corydalis micrantha
8	Plants rarely bearing cleistogamous flowers; seeds ca. 2 mm diam.	> 9
9	Seeds appearing distinctly rough under magnification.	Corydalis curvisiliqua
9	Seeds appearing essentially smooth under magnification.	Corydalis aurea