Flora of North America species comparison

erect, ovoid, becoming cylindric with age, 11–23(–40) × (4.5–)5.5–7(–10) cm;

ribs (13–)15–19(–21), crests rather sharply undulate;

areoles 5–11 mm apart.

mostly nearly erect when young, frequently decumbent in old age, cylindric, 4–15 × 2–3(–7) cm;

ribs (6–)7–10, crests strongly undulate;

areoles 10–15 mm apart.

19–28 per areole, straight, appressed (radial spines) or spreading in all directions (central spines), presenting relatively bristly appearance (except when spines very short, and then having relatively smooth appearance as in E. pectinatus), pink to pale yellow, white, or tan, less often dark brown or purplish, annual growth increments marked (often vaguely) by rings of spines with contrasting colors;

radial spines (16–)17–25(–28) per areole, 5–15(–25) mm;

central spines (2–)8–12(–15) per areole, terete, largest spines 4.5–9.5(–14) mm.

8–12 per areole, straight, appressed-spreading (radial spines) or projecting to appressed (central spines), white, yellow, or brown and white;

radial spines 7–10 per areole, to 15 mm;

central spines 1(–4) per areole, brown, terete, to 25 mm.

7–8.5(–10) × 7–12 cm;

flower tube 10–20 × to 10 mm;

flower tube hairs 1–3 mm;

inner tepals either yellow (rarely orange-yellow, sometimes becoming salmon- or rose-pink with age), or rose-pink to magenta, proximal 5–30% green in either case, (25–)32–69(–77) × 8–23 mm, tips relatively thin and delicate;

anthers yellow;

nectar chamber 2–6 mm.

funnelform, 7–9 × 7–12 cm;

flower tube 20–30 × 10–30 mm;

flower tube hairs 1 mm;

inner tepals yellow, proximally orange-red to purple, 15–40 × 10–20 mm, tips relatively thin and delicate;

filaments yellowish to orange-red;

anthers yellow;

nectar chamber 4–6 mm.

dark dull purplish to maroon (sometimes remaining green), 2–3.5 cm, pulp white to purplish pink.

green, 15–25 mm, pulp white.

= 44.

= 22.