Flora of North America species comparison

segments not easily detached, green, elliptic to narrowly to broadly obovate to circular, 4–27 × 2–18 cm, low tuberculate;

areoles 4–14 per diagonal row across midstem segment, subcircular, 3–6 mm;

wool tan to brown.

segments obovate, 8–10 × 5–8 cm;

areoles (6–)8–10 per diagonal row across midstem segment, 10–17 mm apart.

at all or only distal areoles of stem segment, terete to flattened, stout to acicular to bristlelike, straight to curling, of 1 or 2 kinds;

if 1 kind: 0–18 per areole, spreading and curling in various directions, sometimes straight, erect, ascending to deflexed, yellow to dark brown to black, turning gray, pink-gray to gray-brown, longest (35–)40–90(–185) mm;

if ± 2 kinds: major spines (0–)1–5, reflexed to porrect, yellow-brown to brown to gray, longest 20–150 mm;

minor spines (0–)5–11, deflexed, white to white-gray, longest 4–16 mm.

in most areoles, grading in size and orientation;

longer spines (1–)2–6 per areole, slightly descending porrect, ascending near apex, (yellow-gray to) brown to black, (40–)50–80 mm;

smaller spines 4–6 per areole, reflexed, gray-white.

inconspicuous, in narrow, tidy crescent at adaxial edge of areole or in broad, brushy crescent and tuft, yellow to reddish, aging brown, to 10 mm.

inner tepals yellow to magenta throughout, 25–40 mm;

filaments white, yellow, or red to magenta (flowers may superficially appear bicolored);

anthers yellow;

style white to pale pink;

stigma lobes green.

tan to brown, ± cylindric, 15–45 × 12–25 mm, dry at maturity, glabrous, sometimes burlike;

areoles 10–33, each or only distal areoles bearing 3–16 spines, 4–20 mm.

stout;

areoles 11–21, bearing 4–8 spines, 4–18 mm.

tan to gray, flattened, warped, oblong to subcircular, 3–7 × 2–4 mm;

girdle protruding 1–2 mm.

= 44, 66.