Flora of North America species comparison

diffuse, upper portion not enlarged.

diffuse, upper portion not enlarged.

nearly spheric to more often cylindric or long cylindric, 5–30 × 5–7 cm, firm;

tubercles 5–12 × 3–7 mm;

axils woolly, bearing 4–15 bristles (0 in young growth) as long as tubercles;

cortex and pith not mucilaginous;

latex absent.

slender cylindric, 4.5–10(–30) × 2–3.5 cm, tapered at base, firm;

tubercles 5–9 × 5–9 mm;

axils appearing naked;

cortex and pith not mucilaginous;

latex absent.

14–26 per areole, pinkish or reddish brown to black, glabrous;

radial spines 11–22 per areole, usually white, bristlelike, 5–7 mm, stiff;

central spines (1–)3–4 per areole, abaxial 1 porrect, hooked, longer, stouter, adaxial central spines ascending with radial spines;

subcentral spines 0.

14–22(–23) per areole, whitish to yellowish near base, pale reddish brown to nearly black toward tips, glabrous;

radial spines 13–21 per areole, whitish, with reduced dark tips relative to central spines, bristlelike, 5–9 × 0.16 mm, stiff;

central spines 1(–3) per areole, porrect, hooked, (7–)9–18 × 0.16–0.45 mm;

subcentral spines 0(–3) per areole, adaxial to central spines, ± transitional to radial spines.

10–22 mm;

outermost tepals entire or short fringed;

inner tepals cream, usually with pinkish or reddish midstripes, longer in bisexual flowers, 5.4 mm diam.;

stigma lobes yellow to greenish yellow or brownish green, 8 mm.

1.5–3 × 1.2–2.5 cm;

outermost tepal margins densely short fringed;

inner tepals white or pinkish with bright rose-pink midstripes, 14–19 × 5–7 mm;

stigma lobes magenta, 3–6 mm.

bright scarlet, clavate or ovoid, 10–25(–35) × 10 mm, juicy only in fruit walls;

floral remnant persistent.

bright red, obovoid to nearly clavate, 7–15 × 4–7 mm, juicy only in fruit walls;

floral remnant persistent.

black, 0.8 × 0.6 mm, pitted;

testa hard;

anticlinal cell walls straight (not undulate);

interstices conspicuously wider than pit diameters;

pits bowl-shaped.

black, 0.9–1.1 × 0.8–1.1 × 0.7 mm, pitted;

testa hard, brittle;

anticlinal cell walls straight (not undulate);

interstices conspicuously wider than pit diameters;

pits bowl-shaped.

= 66.

= 22.