Flora of North America species comparison

unbranched or branched near base, depressed-spheric, spheric, cylindric, or elongate-cylindric, 4.5–45 × 3.5–14.5 cm;

ribs (10–)13(–16), tubercles evident on ribs.

unbranched, cylindric or obconic cylindric, 2–7.5(–8) × 1.2–2.5 cm;

ribs not evident, tubercles prominent.

frequently obscuring stems;

radial spines 8–17 per areole, usually white, sometimes brown or purplish pink, 6–36 mm;

central spines (3–)4–6(–8) per areole, 1–5 hooked;

abaxial central spine usually purple black, hooked, 15–72 × 0.6–1 mm;

lateral spines 2–6 per areole, similar to abaxial, usually shorter, usually not hooked;

adaxial central spine usually white (rarely gray, straw colored, pink, or reddish brown), flat to angled or terete; straight (rarely contorted), 17–82(–90) × 0.7–1.5(–3) mm.

dense, obscuring stems;

radial spines 5–10 per areole, white, straight, flat, (2–)3–5 × 0.3–0.6 mm;

central spines 1(–4) per areole;

abaxial central spine 1 per areole, whitish to tan or gray, straight, wavy, twisting, or curling, flat, flexible, papery, with obscure adaxial midrib, sometimes pointing upward and obscuring apex of plant, lacking hook, 15–45(–50) × 1–1.5 mm;

lateral or adaxial central spines 0(–3) per areole, white to tan, (3–)20–40 × 0.5–1 mm.

funnelform to campanulate, (2–)3–5.7(–7) × 2.5–5.5(–8) cm;

outer tepals with greenish or brownish purple midstripes and rose to purple, pink, yellow, or white margins, oblanceolate, 25–50 × 6–10 mm, mucronate, margins entire;

inner tepals rose to purple, pink, or yellow (rarely white), oblanceolate, 15–55 × 6–12 mm, margins entire to fringed, apex mucronate;

filaments purple, yellow, or green;

anthers yellow;

ovary papillate, appearing granular.

funnelform to narrowly campanulate, 2–2.5 × 1–2.5 cm;

outer tepals with green-purple to red-brown midstripes and cream to white margins, cuneate-spatulate, usually 9–20 × 1–3 mm, finely toothed;

inner tepals white with brown midstripes, largest tepals oblanceolate, 15–20 × 3.5–4.5 mm, apex acute to mucronate;

filaments white to greenish yellow;

anthers cream to pale yellow.

irregularly dehiscent, green turning reddish pink, 10–30 × 10–15 mm;

scales few, membranous fringed.

indehiscent or irregularly dehiscent, green, subspheric, 4–6 × 3–5 mm, dry at maturity;

scales few or none.

dark brown to black, 2.5–3.5 × 1.5–3 mm;

testa with rounded papillae.

black, 2.5–3 × 2–2.5 mm, shiny;

testa with fine, rounded papillae.