Corydalis caseana

A. Gray

Proc. Amer. Acad. Arts 10: 69. 1874.

Common names: Fitweed
Treatment appears in FNA Volume 3.

Plants perennial, glaucous, from large, fleshy roots. Stems 1-several, 10-15 dm or more. Leaves ca. 5, compound, to 10 dm; blade with 2-4 orders of leaflets and lobes; ultimate lobes of proximal cauline leaves narrowly to broadly elliptic, 1-5 cm, apiculate. Inflorescences paniculate, 50 or more flowers on primary axis; bracts inconspicuous, linear or narrowly elliptic, rarely wider, proximal bracts ca. 10 mm, distal greatly reduced. Flowers ascending or spreading; pedicel 3-5 mm; sepals persistent, round and irregularly dentate to ovate, lunate, or attenuate-lanceolate with broad, sometimes lobed base, 2-3 mm; petals light pink to white, inner ones tipped reddish purple; spurred petal often incurved, 16-25 mm, spur tapered or not, 9-16 mm, apex obtuse, crest absent, inconspicuous, or extending into beak beyond petal apices, marginal wing narrow to broad, conspicuous; unspurred outer petal 10-15 mm; inner petals 7-12 mm, claw 3-5 mm; nectariferous spur 1/2-3/4 length of petal spur; style 3-4 mm; stigma roughly rectangular, with 8 papillae. Capsules reflexed, ellipsoid, 10-15 × ca. 3-5 mm. Seeds ca. 2.5 mm diam., with numerous minute protuberances.


Calif., Colo., Idaho, N.Mex., Oreg., Utah


Subspecies 5 (5 in the flora).

Significant livestock losses have been caused by ingestion of Corydalis caseana, which is palatable to both cattle and sheep, despite the toxicity.

Selected References



1 Outer petals with marginal wing narrow or absent, apex of unspurred outer petal acute; California. Corydalis caseana subsp. caseana
1 Outer petals with marginal wing moderately to highly developed, apex of unspurred outer petal not acute; other than California. > 2
2 Outer petals with marginal wing scarcely revolute, apex rounded, sometimes minutely apiculate or notched. > 3
2 Outer petals with marginal wing distinctly revolute, apex distinctly notched. > 4
3 Outer petals minutely apiculate; stems mostly 10–15 dm; Colorado and New Mexico. Corydalis caseana subsp. brandegei
3 Outer petals not minutely apiculate, occasionally minutely notched; stems mostly 4–10 dm; Utah. Corydalis caseana subsp. brachycarpa
4 Inflorescences profusely branching; outer petals with marginal wing moderately developed, minutely eroded; n Idaho. Corydalis caseana subsp. hastata
4 Inflorescences not profusely branching; outer petals with marginal wing highly developed, not minutely eroded; ne Oregon and s Idaho. Corydalis caseana subsp. cusickii