3. Corydalis flavula (Raf.) DC. (pale corydalis, yellow fumewort, yellow
harlequin)
Pl. 418 g, h;
Map 1863
Plants green or
sometimes dull gray and more or less glaucous. Stems 5–30 cm long, mostly
loosely ascending from a spreading base. Basal and lower stem leaves with the
petiole 4–8 cm long, the upper leaves usually sessile. Leaf blades 1–4 cm long,
with 5 or 7 pinnae, these deeply several-lobed, the ultimate segments linear to
narrowly oblong or less commonly broadly elliptic. Inflorescences mostly not
extending past the foliage, those with open flowers (3–)6–12-flowered racemes,
those with cleistogamous flowers 1–5-flowered clusters. Flower stalks (except
sometimes in cleistogamous flowers) (6–)9–22 mm long, ascending at flowering,
often pendant at fruiting. Corollas pale yellow or less commonly brighter
yellow, the upper outer petal 7–9 mm long, the spur (except in cleistogamous
flowers) 1.5–2.0 mm long, incurved, the concave apical portion usually with an
irregular, wavy or toothed crest. Fruits 14–25 mm long, relatively straight, glabrous,
not appearing mealy. Seeds 1.9–2.1 mm long, the surface finely pebbled, the
sharply angled rim with a minute marginal ridge. 2n=16. March–May.
Scattered,
mostly south of the Missouri River (eastern [mostly northeastern] U.S. west to
Nebraska and Oklahoma; Canada). Bottomland forests, mesic upland forests in
ravines, bases of bluffs, banks of streams and rivers; also shaded roadsides.
This is the most
abundant species of Corydalis in the state. It is a relatively
inconspicuous wildflower. Some or all of the flowers on a plant often are
cleistogamous.