Flora of North America species comparison

(when present) unbranched and erect or, sometimes, few branches from near base, in robust plants stems and caudex hollow and greatly enlarged, especially toward base, densely leafy, 5–35 cm.

erect, branched below and just above ground, branched also proximal to inflorescences, (40–)60–250 cm.

in a basal rosette, sometimes also cauline, (1.4–)6–15(–28) × (0.2–)1–3.5(–5.6) cm;

petiole (0.9–)3.5–8(–14) cm;

blade oblanceolate to linear-oblanceolate, pinnatifid or 2-pinnatifid to shallowly pinnately lobed, margins sinuate-dentate or subentire, apex obtuse.

in a basal rosette and cauline, basal 3–13 × 0.6–2.5 cm, blade spatulate to oblanceolate, cauline (1–)2.5–12 × 0.1–1 cm, blade linear to narrowly oblanceolate, margins slightly to conspicuously sinuate-dentate.

slender.

usually 1–4, rarely more, opening per day, 1–2 hours before sunset;

sepals (7–)12–25(–30) mm;

petals yellow, fading reddish orange to purple, obcordate to obovate, (6–)13–35(–40) mm;

filaments 6–16 mm, anthers 3–10 mm;

style (32–)40–90(–100) mm, stigma exserted beyond anthers or surrounded by them.

4-merous, zygomorphic, opening near sunset;

floral tube 3–9 mm;

sepals 6–12 mm;

petals white, fading dark pink to red, slightly unequal, elliptic-obovate, 7–11 mm;

stamens presented in lower 1/2 of flower, filaments 3–7 mm, anthers 2.5–5 mm, pollen 90–100% fertile;

style 9.5–19 mm, stigma exserted beyond anthers at anthesis.

woody in age, sigmoid or curved to nearly straight, lanceoloid to ovoid, 4-angled, 10–45(–60) × 4–8 mm, beak 4–15 mm, dehiscent 1/4–2/3 their length;

sessile.

lanceoloid to narrowly ovoid, narrowly 4-winged, 7–12 × 1.5–2.5 mm, tapered to a sterile stipe 2–5 mm.

usually numerous, in 2 rows per locule, obovoid to oblanceoloid, 3–3.5 × 1–1.4 mm, surface thickened above raphe and at distal end into U-shaped structure.

(2 or)3 or 4(or 5), light brown or reddish brown, 1.5–2.5 × 0.8–1.3 mm.

= 14.

= 14.