Flora of North America species comparison

central stem usually erect, usually thickened at base and spongy, branched or unbranched, branches few–several, slender, decumbent to ascending, from base, usually encircling central stem in older plants, 10–40(–100) cm.

usually well-branched distal to base, 50–180 cm.

in a basal rosette and cauline, rosette usually well developed (except subsp. howellii), basal 5–25 × 1–5 cm, cauline 4–12(–18) × 0.5–4 cm;

petiole 1.5–8 cm;

blade rhombic-obovate, lanceolate, or oblanceolate, margins subentire, dentate, or pinnatifid.

in a basal rosette and cauline, basal 8–20 × 1.5–3 cm, blade oblanceolate, margins irregularly toothed to lobed;

cauline 1.5–12 × 0.5–3 cm, blade narrowly elliptic to elliptic or lanceolate, margins subentire or undulate-denticulate.

1–several opening per day near sunset;

buds nodding, weakly or strongly quadrangular or fluted in distal 1/2, with free tips 0–9 mm;

floral tube 20–40 mm;

sepals (13–)15–35 mm, not spotted;

petals white, fading pink to deep pink, broadly obovate or obcordate, 15–44 mm;

filaments 8–15 mm, anthers 5–14 mm;

style 35–60 mm, stigma exserted beyond anthers at anthesis.

4-merous, zygomorphic, opening at sunset;

floral tube 6–13 mm;

sepals 5–13 mm;

petals white, fading pink to red, narrowly elliptic-obovate, 6–12 mm;

filaments 5–10 mm, anthers 2–4 mm, pollen 35–65% fertile;

style 12–15 mm, stigma surrounded by anthers.

spreading, straight to curved, becoming somewhat woody in age, cylindrical to slightly 4-angled, widest toward base, tapering from base to apex, (15–)30–80 × 1.5–5 mm;

sessile.

ellipsoid, 4-angled, 5–9 × 2–3 mm;

sessile.

numerous, in 1 row per locule, buff with dark spots or black, narrowly obovoid, 1.5–2.8 mm.

3–6, light to reddish brown, 2–2.5 × 1–1.3 mm.

= 14.