Cylindropuntia acanthocarpa

(Engelmann & J. M. Bigelow) F. M. Knuth in C. Backeberg and F. M. Knuth

in C. Backeberg and F. M. Knuth, Kaktus-ABC, 124. 1935.

Common names: Buckhorn cholla
Illustrated
Basionyms: Opuntia acanthocarpa Engelmann & J. M. Bigelow Proc. Amer. Acad. Arts 3: 308. 1856
Treatment appears in FNA Volume 4. Mentioned on page 104, 107, 110, 111.

Trees or shrubs, sparsely to densely branched, 1–2 (–4) m. Stem segments firmly attached, cylindric, 10–30 (–50) × 2–2.5 (–3) cm; tubercles prominent, narrow to broad, 1.5–4.5 cm; areoles elliptic to subcircular, 4–5.5 × 4–5 mm; wool white or yellowish to tan, aging gray-black. Spines 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 redbrown, aging gray, the central spine longest, 12–30 (–38) mm; sheaths white to grayish with yellow to golden tips, baggy to tight-fitting. Glochids in inconspicuous to small adaxial tuft, yellow to brown, 0.5–2 mm. Flowers: 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. Fruits 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. Seeds 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.

Distribution

V4 222-distribution-map.gif

Ariz., Calif., Nev., Utah, n Mexico

Discussion

Varieties 4 (4 in the flora).

Cylindropuntia acanthocarpa hybridizes with C. abyssi, C. echinocarpa (= C. ×deserta), C. bigelovii (= C. ×campii), C. leptocaulis (see C. ×tetracantha), C. ×multigeniculata, C. spinosior, C. versicolor, and C. whipplei (= C. congesta). Hybrids of C. acanthocarpa and C. ×multigeniculata are more open in habit, with longer stem segments than C. ×multigeniculata and with reddish filaments like C. acanthocarpa.

Selected References

None.

Key

1 Tubercles 2.5-4.5 cm, broad; stem segments gray-green; spines of adjacent areoles not or barely interlaced, 6-11(-14) per areole; fruits bearing few spines or sometimes spineless Cylindropuntia acanthocarpa var. thornbe
1 Tubercles (1-)1.5-2.5(-3) cm, broad to narrow; stem segments green to yellow-green; spines of adjacent areoles interlaced; fruits densely spiny, sometimes burlike > 2
2 Abaxial 5-7 spines deflexed, usually subparallel, whitish to light brown; tubercles broad, oval; shrubs with few, ascending branches Cylindropuntia acanthocarpa var. acantho
2 Abaxial (14-)18-30+ spines deflexed to divergent, spreading, pale yellow to red-brown; tubercles narrowly elliptic; shrubs with few to many, spreading branches > 3
3 Branches usually at acute angles; stem segments yellowish green, usually long, commonly 15-30 cm; spines 18-30+, yellow to tan, sheaths baggy; inner tepals yellow Cylindropuntia acanthocarpa var. colorad
3 Branches usually at obtuse angles; stem segments green to dark green, usually short, commonly 8 -20 cm; spines 14-18(-23) per areole, yellow or red-brown, sheaths tight; inner tepals yellow to bronze to brick red Cylindropuntia acanthocarpa var. major
subterete +  and flattened +
ascending-divergent +
gray +, tan +  and deep redbrown +
cushionlike +
gray +  and tan +
0.07 cm0.7 mm <br />7.0e-4 m <br /> (0.5 cm5 mm <br />0.005 m <br />) +
deciduous +  and persistent +
0.4 cm4 mm <br />0.004 m <br /> (0.55 cm5.5 mm <br />0.0055 m <br />) +
12 +  and 30 +
elliptic +  and subcircular +
0.4 cm4 mm <br />0.004 m <br /> (0.5 cm5 mm <br />0.005 m <br />) +
Donald J. Pinkava +
(Engelmann & J. M. Bigelow) F. M. Knuth in C. Backeberg and F. M. Knuth +
Opuntia acanthocarpa +
3 cm30 mm <br />0.03 m <br /> (3.8 cm38 mm <br />0.038 m <br />) +
1.2 cm12 mm <br />0.012 m <br /> (3 cm30 mm <br />0.03 m <br />) +
proliferating +
flattened +  and cylindric +
Buckhorn cholla +
Ariz. +, Calif. +, Nev. +, Utah +  and n Mexico +
15 cm150 mm <br />0.15 m <br /> (30 cm300 mm <br />0.3 m <br />) +
0.2 cm2 mm <br />0.002 m <br /> (15 cm150 mm <br />0.15 m <br />) +
spiny +  and spineless +
indehiscent +
persistent +, long +  and deciduous +
15mm;35mm +
tuberculate +
obconic +  and ellipsoid +
dry +  and fleshy +
1.5 cm15 mm <br />0.015 m <br /> (2 cm20 mm <br />0.02 m <br />) +
0.05 cm0.5 mm <br />5.0e-4 m <br /> (0.2 cm2 mm <br />0.002 m <br />) +
2 cm20 mm <br />0.02 m <br /> (3 cm30 mm <br />0.03 m <br />) +
deciduous +
flattened +  and conic +
0 cm0 mm <br />0 m <br /> (3 cm30 mm <br />0.03 m <br />) +
succulent +
tuberculate +
fluted;spheric;depressed-spheric or club-shaped +
tinged color +
sometimes covered by outgrowths of proximal portion of style base or of flower tube wall +  and open +
persistent +  and deciduous +
ridgelike +  and nipple--shaped +
in C. Backeberg and F. M. Knuth, Kaktus-ABC, +
3;2;2;30 +
tuberlike +
0.04 cm0.4 mm <br />4.0e-4 m <br /> (1.2 cm12 mm <br />0.012 m <br />) +
0.35 cm3.5 mm <br />0.0035 m <br /> (0.5 cm5 mm <br />0.005 m <br />) +
warped;squarish;angular +
0.3 cm3 mm <br />0.003 m <br /> (0.45 cm4.5 mm <br />0.0045 m <br />) +
tight-fitting +
Illustrated +
deciduous +  and persistent +
conspicuous +
0 (?) +  and 5 (?) +
flattened +
hard +  and rigid +
decurrent +
winged +  and unsegmented +
tuberculate +  and smooth +
30 cm300 mm <br />0.3 m <br /> (50 cm500 mm <br />0.5 m <br />) +
2.5 cm25 mm <br />0.025 m <br /> (3 cm30 mm <br />0.03 m <br />) +
10 cm100 mm <br />0.1 m <br /> (30 cm300 mm <br />0.3 m <br />) +
2 cm20 mm <br />0.02 m <br /> (2.5 cm25 mm <br />0.025 m <br />) +
segmented +
woody +  and succulent +
white +  and light green +
white +  and light green +
Opuntia sect. Cylindropuntia +
adventitious +
tuberlike +
epipetric +  and epiphytic +
Cylindropuntia acanthocarpa +
Cylindropuntia +
species +
dull +  and glossy +
yellow +  and golden +
1.5 cm15 mm <br />0.015 m <br /> (4.5 cm45 mm <br />0.045 m <br />) +
narrow +  and broad +
shrub +  and tree +
terrestrial;epiphytic or epipetric +
gray-black +, yellowish +  and tan +