Cordylanthus rigidus

(Bentham) Jepson

Fl. W. Calif. ed. 2, 387. 1911.

Basionym: Adenostegia rigida Bentham in J. Lindley, Nat. Syst. Bot., 445. 1836
Treatment appears in FNA Volume 17. Treatment on page 675. Mentioned on page 670.

Stems ascending, 30–100(–150) cm, pubescent, hirsute, glabrescent, puberulent, sparsely hispid, or downy. Leaves puberulent and often hirsute; proximal 10–40 mm, margins 3-lobed, lobes 1–3 mm wide; distal 10–30 × 0.5–1.5 mm, margins entire or 3-lobed. Inflorescences capitate spikes, 2–15-flowered; bracts 5–10, 5–20 mm, margins entire or 3-lobed, lobes purplish black, ivory, or green distally, linear-lanceolate to linear or slightly spatulate. Pedicels: bracteoles 14–20 mm, margins entire or toothed. Flowers: calyx 10–20 mm, tube 1–2 mm, apex entire or 2-fid, cleft 0–1 mm; corolla pale yellow with purple veins and an abaxial, U-shaped, purple mark, 8–20 mm, throat 5–10 mm diam., abaxial lip 6–10 mm, ca. equal to and appressed to adaxial; stamens 4, filaments hairy, fertile pollen sacs 2 per filament, subequal. Capsules oblong-ovoid, 8–12 mm. Seeds 10–25, dark brown, oblong-ovoid, 1.5–2 mm, striate. 2n = 28.


Subspecies 4 (4 in the flora).

Cordylanthus rigidus is variable, with many locally distinctive populations that intergrade with each other and with nearby species.

Selected References



1 Proximal bracts 5–12 mm, shorter than flowers. Cordylanthus rigidus subsp. brevibracteatus
1 Proximal bracts 10–20 mm, equal to or longer than flowers. > 2
2 Proximal bracts: midlobes linear, 0.5–1 mm wide, dark purple distally. Cordylanthus rigidus subsp. setigerus
2 Proximal bracts: midlobes linear-lanceolate or lanceolate, 1–2.5 mm wide, green or red distally. > 3
3 Stems pubescent and hirsute, hairs stiff; proximal bracts: midlobe apices retuse. Cordylanthus rigidus subsp. rigidus
3 Stems downy to puberulent, hairs soft; proximal bracts: midlobe apices acute to retuse. Cordylanthus rigidus subsp. littoralis