Opuntia polyacantha


Suppl. Pl. Succ., 82. 1819.

Common names: Starvation pricklypear
Basionym: Cactus ferox Nuttall Gen. N. Amer. Pl. 1: 296. 1818, not Willdenow 1813
Synonyms: Tunas polyacantha (Haworth) Nieuwland & Lunell
Treatment appears in FNA Volume 4. Mentioned on page 124, 125, 132, 133.

Shrubs, low, 10–25 cm, with ± prostrate branches. Stem 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. Spines 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. Glochids 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. Flowers: 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. Fruits 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. Seeds tan to gray, flattened, warped, oblong to subcircular, 3–7 × 2–4 mm; girdle protruding 1–2 mm.


V4 283-distribution-map.gif

Alta., Sask., Ariz., Calif., Colo., Idaho, Kans., Mont., N.Dak., N.Mex., Nebr., Nev., Okla., S.Dak., Tex., Utah, Wyo., n Mexico.


Varieties 5 (5 in the flora).

Populations of Opuntia polyacantha with spines few or absent (especially var. hystricina) were the basis for several names including O. juniperina, O. utahensis, and O. rhodantha.

Selected References



1 Areoles 4-6 per diagonal row across midstem segment; stem segments 4-7 × 2-3(-5) cm, elliptic to very narrowly obovate; Texas, New Mexico, Mexico Opuntia polyacantha var. arenaria
1 Areoles 6-14 per diagonal row across midstem segment; stem segments 6-27 × 5-18 cm, obovate to circular or, if elliptic, longer than 9 cm; widespread in w United States and Canada > 2
2 Spines of 2 kinds: major spines 1-3 per areole, usually deflexed on terminal stem segment, but sometimes ascending at stem segment apex; minor spines 1-3 per areole, deflexed, white, subtending major spines > 3
2 Spines of 1 kind, grading in length, from ascending to deflexed, 7-18 per areole, longest spines of terminal stem segment porrect to ascending, shorter spines deflexed to porrect > 4
3 Longest spines 2-4 cm; areoles 6-13 mm apart; stem segments 6-12 cm; Great Plains, n and e Great Basin Desert Opuntia polyacantha var. polyacantha
3 Longest spines 4.5-12 cm; areoles 12-30 mm apart; stem segments 10-27 cm; Arizona and Utah border Opuntia polyacantha var. nicholii
4 Spines usually dark brown, those of proximal stem segments like those of terminal stem segments, porrect to ascending, straight and stiff; fruit areoles 11-21, spiny but not burlike Opuntia polyacantha var. hystricina
4 Spines usually pale, those of proximal stem segments not like those of terminals stem segments, more numerous, longer and more reflexed, straight or flexuous and/or hairlike or threadlike; fruit areoles 20-33, spiny, forming dense bur Opuntia polyacantha var. erinacea
... more about "Opuntia polyacantha"
Donald J. Pinkava +
Haworth +
Cactus ferox +
Starvation pricklypear +
Alta. +, Sask. +, Ariz. +, Calif. +, Colo. +, Idaho +, Kans. +, Mont. +, N.Dak. +, N.Mex. +, Nebr. +, Nev. +, Okla. +, S.Dak. +, Tex. +, Utah +, Wyo. +  and n Mexico. +
Suppl. Pl. Succ., +
Illustrated +
Tunas polyacantha +
Opuntia polyacantha +
species +