Opuntia macrocentra

Engelmann

Proc. Amer. Acad. Arts 3: 292. 1856.

Common names: Black-spined pricklypear purple pricklypear
Illustrated
Synonyms: Opuntia violacea Engelmann ex B. D. Jackson Opuntia violacea var. castetteri L. D. Benson Opuntia violacea var. macrocentra (Engelmann) L. D. Benson
Treatment appears in FNA Volume 4. Mentioned on page 138.

Shrubs, erect to decumbent, to 1 m. Stem segments not easily detached, purple (particularly under stress) to green with purple near areoles and margins of stem segment, flattened, broadly obovate to subcircular, thickish, 7–20 × 6–18 cm; areoles 6–8 (–10) per diagonal row across midstem segment, elliptic to circular, 3–7 × 2.5–5 mm; wool tan to whitish, aging black. Spines 0 or 1–15+ per areole, few and at distal areoles or many and on most areoles, usually erect to spreading, appearing unruly, sometimes deflexed, straight or curving, acicular, often flexible, subterete to flattened basally; longer ones reddish-brown to ± black (rarely yellow to red in w Texas), or partly to wholly white, 30–120 (–170) mm; reflexed spine rarely present, 1 in some areoles, short, whitish. Glochids dense in crescent at adaxial edge of areole and well-developed subapical tuft, reddish yellow, aging brown, 2–3 (–6) mm. Flowers: inner tepals yellow with red basal portions, obovate-apiculate, 25–40 mm; filaments and anthers yellowish; style cream; stigma lobes green. Fruits red to purplish, obovoid to barrel-shaped, 25–40 × 20–23 mm, fleshy or ± juicy, glabrous, spineless; umbilicus 8–10 mm deep; areoles 22–44. Seeds yellowish, suborbicular to reniform, angled, 5–7 × 3.5–5 mm, sides flattened; girdle protruding 0.8–1.2 mm. 2n = 22, 44.


Phenology: Flowering spring (Mar–Jun).
Habitat: Desert uplands, grasslands, oak woodlands, sandy desert flats, rocky hills and valleys
Elevation: 900-1600 m

Distribution

V4 261-distribution-map.gif

Ariz., N.Mex., Tex., Mexico (Chihuahua), Mexico (Coahuila), Mexico (Sonora)

Discussion

Opuntia macrocentra var. minor is represented by relatively short and compact shrubs with a glochid pattern of a dense crescent in the adaxial edge of the areoles like the species and a much taller tuft of spreading glochids. This variety, which grows along the western side of the Rio Grande in Big Bend, Texas, appears best interpreted as a tetraploid hybrid between tetraploid putative parents, Opuntia macrocentra and O. tortispina.

Selected References

None.

Lower Taxa

None.
... more about "Opuntia macrocentra"
cushionlike +
elliptic +  and circular +
0.8 cm8 mm <br />0.008 m <br /> (1 cm10 mm <br />0.01 m <br />) +
0.7 cm7 mm <br />0.007 m <br /> (1 cm10 mm <br />0.01 m <br />) +
deciduous +  and persistent +
0.3 cm3 mm <br />0.003 m <br /> (0.7 cm7 mm <br />0.007 m <br />) +
22 +  and 44 +
obovate +  and circular +
0.25 cm2.5 mm <br />0.0025 m <br /> (0.5 cm5 mm <br />0.005 m <br />) +
Donald J. Pinkava +
Engelmann +
proliferating +
flattened +  and cylindric +
Black-spined pricklypear +  and purple pricklypear +
Ariz. +, N.Mex. +, Tex. +, Mexico (Chihuahua) +, Mexico (Coahuila) +  and Mexico (Sonora) +
900-1600 m +
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 />) +
burlike +  and spiny +
red;purplish +
straight +
indehiscent +
persistent +, long +  and deciduous +
25mm;40mm +
proliferating +
tuberculate +  and smooth +
obovoid +  and barrel-shaped +
juicy +  and fleshy +
2 cm20 mm <br />0.02 m <br /> (2.3 cm23 mm <br />0.023 m <br />) +
0.08 cm0.8 mm <br />8.0e-4 m <br /> (0.12 cm1.2 mm <br />0.0012 m <br />) +
0.3 cm3 mm <br />0.003 m <br /> (0.6 cm6 mm <br />0.006 m <br />) +
0.2 cm2 mm <br />0.002 m <br /> (0.3 cm3 mm <br />0.003 m <br />) +
foveolate +  and reticulate +
Desert uplands, grasslands, oak woodlands, sandy desert flats, rocky hills and valleys +
oblong +  and spatulate +
2.5 cm25 mm <br />0.025 m <br /> (4 cm40 mm <br />0.04 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 +
open +  and simple +
sometimes covered by outgrowths of proximal portion of style base or of flower tube wall +  and open +
persistent +  and deciduous +
Flowering spring (Mar–Jun). +
ridgelike +  and nipple--shaped +
Proc. Amer. Acad. Arts +
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 />) +
0.5 cm5 mm <br />0.005 m <br /> (0.7 cm7 mm <br />0.007 m <br />) +
angled;suborbicular;reniform +
0.35 cm3.5 mm <br />0.0035 m <br /> (0.5 cm5 mm <br />0.005 m <br />) +
flattened +
Illustrated +
not sheathed +
12 cm120 mm <br />0.12 m <br /> (17 cm170 mm <br />0.17 m <br />) +
whitish +, reddish-brown +  and more or less black or +
curving +  and straight +
deciduous +  and persistent +
reflexed +  and deflexed +
conspicuous +
with hairlike bristles +  and setose +
1 (?) +  and 15 (?) +
subterete +  and flattened +
3 cm30 mm <br />0.03 m <br /> (12 cm120 mm <br />0.12 m <br />) +
hard +  and rigid +
decurrent +
winged +  and unsegmented +
tuberculate +  and smooth +
60 cm600 mm <br />0.6 m <br /> (120 cm1,200 mm <br />1.2 m <br />) +
purple +  and green +
7 cm70 mm <br />0.07 m <br /> (20 cm200 mm <br />0.2 m <br />) +
pubescent +  and glabrous +
nearly smooth +  and tuberculate +
6 cm60 mm <br />0.06 m <br /> (18 cm180 mm <br />0.18 m <br />) +
segmented +
woody +  and succulent +
Opuntia violacea +, Opuntia violacea var. castetteri +  and Opuntia violacea var. macrocentra +
adventitious +
tuberlike +
epipetric +  and epiphytic +
Opuntia macrocentra +
species +
dull +  and glossy +
yellow +  and paler +
segmented +
0.8 cm8 mm <br />0.008 m <br /> (1 cm10 mm <br />0.01 m <br />) +
terrestrial;epiphytic or epipetric +
erect +  and decumbent +
black +, tan +  and whitish +