Grusonia aggeria

(Ralston & Hilsenbeck) E. F. Anderson

Cact. Succ. J. (Los Angeles) 71: 325. 1999.

Basionyms: Opuntia aggeria Ralston & Hilsenbeck Madroño 36: 226, fig. 2. 1989
Treatment appears in FNA Volume 4. Treatment on page 119.

Shrubs, forming clumps, 3–9 cm. Roots tuberlike, 7–8 × 2.5–3 cm. Stem segments short cylindric to clavate, 3.5–9 × 1.5–3 cm; tubercles 8–18 (–22) mm; areoles circular 3–4 mm in diam.; wool yellowish white. Spines (1–) 5–15 per areole, mostly in distal areoles, 3–5 cm; major 1–3 abaxial spines deflexed, usually chalky white (at least adaxially), flattened to angular-flattened, longest central abaxial spine commonly twisted or curved (at times the only spine in depauperate specimens, those mostly from Big Bend region of Texas); major 0–5 adaxial spines divergent, ascending, brown to blackish and sometimes chalky, ± terete. Glochids adaxial in areole, yellow, to 4 mm. Flowers: inner tepals bright-yellow, 25 mm; filaments green; style cream; stigma lobes pale yellow-green. Fruits yellow, aging gray, cylindric to ellipsoid, 20–25 (–50) × 10–15 mm, becoming dry, spineless, glochidiate; areoles 25–35. Seeds yellowish to brownish, ± circular, to 5 mm in diam., with various numbers and sizes of bumps. 2n = 22.


Phenology: Flowering spring (Mar–May).
Habitat: Chihuahuan Desert, sandy or gravelly flats, scrub with creosote bush, lower slopes, limestone or igneous substrates
Elevation: 600-1500 m

Discussion

Grusonia aggeria is based on the “type” of “Opuntia grahamii × O. schottii” described by M. S. Anthony (1956). It is not a hybrid, however, between the two tetraploid putative parental taxa; it is instead a fully fertile, diploid species.

Selected References

None.

Lower Taxa

None.

... more about "Grusonia aggeria"
flattened +  and angular-flattened +
brown +  and blackish and sometimes chalky +
cushionlike +
0.3 cm3 mm <br />0.003 m <br /> (0.4 cm4 mm <br />0.004 m <br />) +
0.1 cm1 mm <br />0.001 m <br /> (0.6 cm6 mm <br />0.006 m <br />) +
deciduous +  and persistent +
25 +  and 35 +
cushionlike +
Donald J. Pinkava +
(Ralston & Hilsenbeck) E. F. Anderson +
curving +
dislodged +
cylindric-clavate +
Opuntia aggeria +
proliferating +
flattened +  and cylindric +
Tex. +  and Mexico (Coahuila) +
600-1500 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 />) +
2.5 cm25 mm <br />0.025 m <br /> (5 cm50 mm <br />0.05 m <br />) +
gray;yellow +
indehiscent +
persistent +, long +  and deciduous +
20mm;25mm +
glochidiate +
cylindric +  and ellipsoid +
1 cm10 mm <br />0.01 m <br /> (1.5 cm15 mm <br />0.015 m <br />) +
not protruding +
0 cm0 mm <br />0 m <br /> (0.4 cm4 mm <br />0.004 m <br />) +
Chihuahuan Desert, sandy or gravelly flats, scrub with creosote bush, lower slopes, limestone or igneous substrates +
25 cm250 mm <br />0.25 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 +
sometimes covered by outgrowths of proximal portion of style base or of flower tube wall +  and open +
persistent +  and deciduous +
Flowering spring (Mar–May). +
ridgelike +  and nipple--shaped +
Cact. Succ. J. (Los Angeles) +
3;2;2;30 +
adventitious +
7 cm70 mm <br />0.07 m <br /> (?) +  and 8 cm80 mm <br />0.08 m <br /> (?) +
tuberlike +
2.5cm +  and 3cm +
0 cm0 mm <br />0 m <br /> (0.5 cm5 mm <br />0.005 m <br />) +
0.04 cm0.4 mm <br />4.0e-4 m <br /> (1.2 cm12 mm <br />0.012 m <br />) +
pubescent +  and glabrous +
flattened;suborbicular +
deciduous +  and persistent +
conspicuous +
5 (?) +  and 15 (?) +
terete +  and strongly flattened +
3 cm30 mm <br />0.03 m <br /> (5 cm50 mm <br />0.05 m <br />) +
hard +  and rigid +
decurrent +
winged +  and unsegmented +
tuberculate +  and smooth +
3.5 cm35 mm <br />0.035 m <br /> (9 cm90 mm <br />0.09 m <br />) +
1.5 cm15 mm <br />0.015 m <br /> (3 cm30 mm <br />0.03 m <br />) +
segmented +
woody +  and succulent +
pale yellow-green +
Corynopuntia +, Marenopuntia +, Micropuntia +, Opuntia subg. Corynopuntia +, Opuntia sect. Clavatae +  and Opuntia (sect. Undefined) ser. Clavatae +
adventitious +
tuberlike +
epipetric +  and epiphytic +
Grusonia aggeria +
Grusonia +
species +
dull +  and glossy +
1.8 cm18 mm <br />0.018 m <br /> (2.2 cm22 mm <br />0.022 m <br />) +
0.8 cm8 mm <br />0.008 m <br /> (1.8 cm18 mm <br />0.018 m <br />) +
conspicuous +
terrestrial;epiphytic or epipetric +
trailing +  and erect +
yellowish white +