Flora of North America species comparison

6–20(–30+) per areole, often accompanied by 0–5 short bristlelike spines at areole margins, usually in distal areoles;

major abaxial spines deflexed to divergent, subterete to flattened;

major adaxial spines ascending-divergent, terete, yellow or tan to deep red-brown, aging gray, the central spine longest, 12–30(–38) mm;

sheaths white to grayish with yellow to golden tips, baggy to tight fitting.

(7–)9–14 per areole, at most areoles, erect or spreading, yellow, aging red- to gray-black with pale tips, terete or abaxial ones slightly flattened, the longest to 3 cm;

marginal bristlelike spines shorter, 0–4;

sheaths pale yellow becoming golden apically, baggy.

in inconspicuous to small adaxial tuft, yellow to brown, 0.5–2 mm.

in adaxial crescent and sometimes small tuft, yellow, inconspicuous, 0.5–2 mm.

inner tepals bright yellow to bronze to brick red, spatulate, 20–30 mm, apiculate-emarginate;

filaments red;

anthers yellow;

style and stigma lobes white to light green.

inner tepals pale reddish maroon-brown, elliptic, of irregular lengths, 8–15 mm, emarginate-apiculate;

filaments green;

anthers yellow;

style and stigma lobes cream.

tan at maturity, obconic to ellipsoid, 15–35 × 15–20 mm, dry, tuberculate, densely to sparsely spiny (rarely spineless), with apical flange above shallow umbilicus;

basal tubercles longest;

areoles 12–30.

easily detached, tan when mature and fertile, globose, 17–24 × 17–21 mm, dry, tuberculate, spineless but bearing numerous very long glochids;

basal tubercles not markedly longer than distal ones (except in sterile fruits);

areoles 30–40.

pale yellow to tan, angular or squarish in outline, warped, 3.5–5 × 3–4.5 mm, sides smooth, each with 2–4 large depressions;

girdle smooth.

pale yellow, rounded-deltoid, slightly flattened, 3–4.5 × 3–4 mm, sides smooth;

girdle smooth, not protruding.

= 22, 33.