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coastal prickly pear, prickly pear

hair-spine prickly pear, panhandle prickly pear, plains prickly pear, starvation prickly-pear

Habit Shrubs, spreading to sprawling, forming large clumps, to 1 × 1–9 m. Shrubs, low, 10–25 cm, with ± prostrate branches.
Stem

segments not disarticulating, green, flattened, elliptic to obovate to rhombic, 15–25(–40) × 6.5–14 cm, ± tuberculate, glabrous, usually glaucous;

areoles 5–7(–8) per diagonal row across midstem segment, prominent, subcircular(-oval), 4–6 × 4–5 mm, enlarging in age;

wool gray.

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

4–11 per areole, in most areoles, yellow with chalky white coat, to yellow with red-brown basal portions, aging reddish gray;

erect ones terete, stout, straight;

abaxial ones reflexed, shorter, to 12 mm;

adaxial spines spreading, longest spines 20–40 mm.

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

moderately dense in crescent at adaxial edge of areole, merging with subapical tuft when present, yellow to red-brown, to 5 mm.

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 dull red throughout, 35–45 mm;

filaments yellow to orange-yellow;

anthers yellow;

style pink to red;

stigma lobes yellow-green to green.

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

dark red-purple throughout, obovoid, 35–50 × 30–35 mm, juicy, glabrous, spineless;

areoles 22–36.

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

gray, subcircular, warped, 3–4.5 mm diam.;

girdle protruding 0.5 mm.

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

girdle protruding 1–2 mm.

2n

= 66.

Opuntia littoralis

Opuntia polyacantha

Phenology Flowering spring (Apr–May).
Habitat Coastal sage scrub, chaparral
Elevation 10-400 m (0-1300 ft)
Distribution
from USDA
Calif (including Channel Islands); Mexico (Baja California)
[WildflowerSearch map]
[BONAP county map]
from FNA
AZ; CA; CO; ID; KS; MT; ND; NE; NM; NV; OK; SD; TX; UT; WY; AB; SK; n Mexico
[WildflowerSearch map]
[BONAP county map]
Discussion

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.

(Discussion copyrighted by Flora of North America; reprinted with permission.)

Key
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
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
var. polyacantha
3. Longest spines 4.5-12 cm; areoles 12-30 mm apart; stem segments 10-27 cm; Arizona and Utah border
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
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
var. erinacea
Source FNA vol. 4. FNA vol. 4.
Parent taxa Cactaceae > subfam. Opuntioideae > Opuntia Cactaceae > subfam. Opuntioideae > Opuntia
Sibling taxa
O. aciculata, O. atrispina, O. aurea, O. aureispina, O. basilaris, O. chisosensis, O. chlorotica, O. cubensis, O. ellisiana, O. engelmannii, O. ficus-indica, O. fragilis, O. humifusa, O. macrocentra, O. macrorhiza, O. microdasys, O. oricola, O. phaeacantha, O. pinkavae, O. polyacantha, O. pottsii, O. pusilla, O. rufida, O. santa-rita, O. stricta, O. strigil, O. tortispina, O. triacantha, O. ×columbiana, O. ×curvispina, O. ×occidentalis, O. ×spinosibacca, O. ×vaseyi
O. aciculata, O. atrispina, O. aurea, O. aureispina, O. basilaris, O. chisosensis, O. chlorotica, O. cubensis, O. ellisiana, O. engelmannii, O. ficus-indica, O. fragilis, O. humifusa, O. littoralis, O. macrocentra, O. macrorhiza, O. microdasys, O. oricola, O. phaeacantha, O. pinkavae, O. pottsii, O. pusilla, O. rufida, O. santa-rita, O. stricta, O. strigil, O. tortispina, O. triacantha, O. ×columbiana, O. ×curvispina, O. ×occidentalis, O. ×spinosibacca, O. ×vaseyi
Subordinate taxa
O. polyacantha var. arenaria, O. polyacantha var. erinacea, O. polyacantha var. hystricina, O. polyacantha var. nicholii, O. polyacantha var. polyacantha
Synonyms O. engelmannii var. littoralis, O. lindheimeri var. littoralis, O. occidentalis var. littoralis, O. semispinosa Cactus ferox, Tunas polyacantha
Name authority (Engelmann) Cockerell: Bull. S. Calif. Acad. Sci. 4: 15. (1905) Haworth: Suppl. Pl. Succ., 82. (1819)
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