Flora of North America species comparison

some-what lax often sprawling, longest stems sometimes prostrate, cylindric, 8–40(–100?) × 3.2–15 cm;

ribs (6–)7–10(–12), crests essentially uninterrupted;

areoles (11–)14–52 mm apart.

erect or slightly decumbent, ovoid to cylindric with age, 7.5–17(–30) × (3.3–)3.8–7.5(–10) cm;

ribs 8–11(–13), crests uninterrupted or undulate (sometimes depth of sinus between areoles is 90% of rib height in flowering plants with juvenile stem morphology);

areoles (12–)15–17(–25) mm apart.

6–14 per areole, straight or central spines slightly curved throughout their lengths, ± opaque, white, pale tan, or purplish gray, often extensively tipped or banded with brown;

radial spines 5–10(–13) per areole, 9.5–40(–47) mm, usually less than 1/2 as long as central spines;

central spines 1–4(–5) per areole, all or mostly projecting, abaxial spine porrect or descending, frequently compressed or angular in cross section (sometimes sulcate, keeled, or striate), (12–)20–84(–96) mm.

(2–)4–12(–16) per areole, straight or curved (radial spines sometimes sinuous);

radial spines spreading, opaquely white, commonly with dark stripe on underside, often with contrasting black or brown spines in same areoles (rarely all brown or all white), aging gray;

radial spines (2–)4–10(–12) per areole, (8–)11–39 mm;

central spines (0–)1(–3) per areole, porrect or ascending, if curved, then usually directed upward, (10–)25–42(–62) mm, abaxial central spine like others in color or darker, flat to sharply angled.

(4.5–)5–7.5 × 5–5.6(–9) cm;

flower tube 10–30 × 10–22(–40) mm;

flower tube hairs 1–2 mm;

inner tepals pink or magenta, darkest proximally, 28–55 × 8–14(–20) mm, tips relatively thin and delicate;

anthers yellow;

nectar chamber 4–6 mm.

5–11 × 5–11 cm;

flower tube 10–15 × 10–30 mm;

flower tube hairs 1–2 mm;

inner tepals magenta [or nearly white], proximally sometimes darker or purplish maroon, 30–70 × (9.5–)12–15 mm, tips relatively thin and delicate;

anthers yellow;

nectar chamber (2–)3.5–6(–8) mm.

pale yellow-green or dull reddish, 20–30 mm, pulp white or pale pink.

bright red, dull carmine, or purplish maroon, less often orange-tan or purplish orange, 20–30(–50) mm, pulp magenta or red.

= 22.

= 22.