Sclerocactus papyracanthus

(Engelmann) N. P. Taylor

Bradleya 5: 94. 1987.

Common names: Grama-grass cactus paper-spined cactus toumeya
IllustratedEndemic
Basionyms: Mammillaria papyracantha Engelmann Mem. Amer. Acad. Arts, n. s. 4: 49. 1849
Synonyms: Pediocactus papyracanthus (Engelmann) L. D. Benson Toumeya papyracantha (Engelmann) Britton & Rose
Treatment appears in FNA Volume 4. Treatment on page 205. Mentioned on page 197, 198, 203, 206, 207.

Stems unbranched, cylindric or obconic cylindric, 2–7.5 (–8) × 1.2–2.5 cm; ribs not evident, tubercles prominent. Spines dense, obscuring stems; radial spines 5–10 per areole, white, straight, flat, (2–) 3–5 × 0.3–0.6 mm; central spines 1 (–4) per areole; abaxial central spine 1 per areole, whitish to tan or gray, straight, wavy, twisting, or curling, flat, flexible, papery, with obscure adaxial midrib, sometimes pointing upward and obscuring apex of plant, lacking hook, 15–45 (–50) × 1–1.5 mm; lateral or adaxial central spines 0 (–3) per areole, white to tan, (3–) 20–40 × 0.5–1 mm. Flowers funnelform to narrowly campanulate, 2–2.5 × 1–2.5 cm; outer tepals with green-purple to redbrown midstripes and cream to white margins, cuneate-spatulate, usually 9–20 × 1–3 mm, finely toothed; inner tepals white with brown midstripes, largest tepals oblanceolate, 15–20 × 3.5–4.5 mm, apex acute to mucronate; filaments white to greenish yellow; anthers cream to pale-yellow. Fruits indehiscent or irregularly dehiscent, green, subspheric, 4–6 × 3–5 mm, dry at maturity; scales few or none. Seeds black, 2.5–3 × 2–2.5 mm, shiny; testa with fine, rounded papillae.


Phenology: Flowering Apr–Jun.
Habitat: Desert grasslands, pinyon-juniper woodlands, Chihuahuan desert scrub
Elevation: 1500-2200 m

Discussion

With long, flexuous, flattened spines and pale flowers, Sclerocactus papyracanthus is surprisingly cryptic in the field. There has been a long debate concerning its taxonomic placement. Chloroplast DNA analyses of J. M. Porter et al. (2000) unambiguously placed this species within Sclerocactus, a position first suggested based on morphologic evidence (K. D. Heil et al. 1981; C. Glass and R. A. Foster 1984).

Selected References

None.

Lower Taxa

None.

whitish +  and tan or gray +
curling +  and straight +
cream +  and pale-yellow +
Acute (?) +  and Mucronate (?) +
cushionlike +
spine-bearing +
circular to linear +
deciduous +  and persistent +
connected +
elliptic +  and pyriform +
0.8 cm8 mm <br />0.008 m <br /> (2 cm20 mm <br />0.02 m <br />) +
Kenneth D. Heil +  and J. Mark Porter +
(Engelmann) N. P. Taylor +
hardened +
Mammillaria papyracantha +
triangular +
0.3 cm3 mm <br />0.003 m <br /> (2 cm20 mm <br />0.02 m <br />) +
white +  and tan +
20mm +  and 40mm +
subulate +  and acicular +
0.05 cm0.5 mm <br />5.0e-4 m <br /> (0.1 cm1 mm <br />0.001 m <br />) +
proliferating +
flattened +  and cylindric +
Grama-grass cactus +, paper-spined cactus +  and toumeya +
mucilaginous +
notched +
Ariz. +, N.Mex. +  and Tex. +
1500-2200 m +
not separating +
white +  and greenish yellow +
6 cm60 mm <br />0.06 m <br /> (7 cm70 mm <br />0.07 m <br />) +
2 cm20 mm <br />0.02 m <br /> (2.5 cm25 mm <br />0.025 m <br />) +
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 />) +
1cm;2.5cm +
2.1 cm21 mm <br />0.021 m <br /> (2.5 cm25 mm <br />0.025 m <br />) +
dehiscent +  and indehiscent +
persistent +, long +  and deciduous +
subspheric +
0.3 cm3 mm <br />0.003 m <br /> (0.5 cm5 mm <br />0.005 m <br />) +
Desert grasslands, pinyon-juniper woodlands, Chihuahuan desert scrub +
4.5 cm45 mm <br />0.045 m <br /> (5 cm50 mm <br />0.05 m <br />) +
1.5 cm15 mm <br />0.015 m <br /> (4.5 cm45 mm <br />0.045 m <br />) +
0.1 cm1 mm <br />0.001 m <br /> (0.15 cm1.5 mm <br />0.0015 m <br />) +
1.5 cm15 mm <br />0.015 m <br /> (2 cm20 mm <br />0.02 m <br />) +
0.35 cm3.5 mm <br />0.0035 m <br /> (0.45 cm4.5 mm <br />0.0045 m <br />) +
deciduous +  and persistent +
rudimentary +
flat +  and terete +
nearly +  and microscopic +
0 cm0 mm <br />0 m <br /> (0.1 cm1 mm <br />0.001 m <br />) +
tuberculate +
fluted;spheric;depressed-spheric or club-shaped +
0.7 cm7 mm <br />0.007 m <br /> (1.5 cm15 mm <br />0.015 m <br />) +
fimbriate +  and entire +
brown +, green-purple +  and redbrown +
0.9 cm9 mm <br />0.009 m <br /> (2 cm20 mm <br />0.02 m <br />) +
deciduous +  and persistent +
Flowering Apr–Jun. +
mucilaginous +
abscission +
ridgelike +  and nipple--shaped +
greenish +  and white +
not evident +
tuberculate +
triangular +
thin +  and broad +
arillate +  and strophiolate +
0.04 cm0.4 mm <br />4.0e-4 m <br /> (1.2 cm12 mm <br />0.012 m <br />) +
0.25 cm2.5 mm <br />0.0025 m <br /> (0.3 cm3 mm <br />0.003 m <br />) +
obovoid;pyriform;obovoid;pyriform;lenticular-reniform;comma--shaped;spheric +
0.2 cm2 mm <br />0.002 m <br /> (0.25 cm2.5 mm <br />0.0025 m <br />) +
Illustrated +  and Endemic +
0.2 cm2 mm <br />0.002 m <br /> (0.3 cm3 mm <br />0.003 m <br />) +
straight +
deciduous +  and persistent +
3mm +  and 5mm +
5 (?) +  and 10 (?) +
annulate-ridged +, hairlike +, daggerlike +, subulate +  and acicular +
hard +  and rigid +
0.03 cm0.3 mm <br />3.0e-4 m <br /> (0.06 cm0.6 mm <br />6.0e-4 m <br />) +
decurrent +
15 cm150 mm <br />0.15 m <br /> (20 cm200 mm <br />0.2 m <br />) +
pale +  and dark green or bluish green +
2cm;7.5cm +
cylindric +  and obconic +
succulent +
1.2cm;2.5cm +
creamy white +, yellow +, green +  and pink +
flat-topped +
tuberculate +
Pediocactus papyracanthus +  and Toumeya papyracantha +
adventitious +
tuberlike +
epipetric +  and epiphytic +
Sclerocactus papyracanthus +
Sclerocactus +
species +
1.5 cm15 mm <br />0.015 m <br /> (5 cm50 mm <br />0.05 m <br />) +
lanceolate to oblanceolate +
0.4 cm4 mm <br />0.004 m <br /> (1.2 cm12 mm <br />0.012 m <br />) +
dull +  and glossy +
papillate +
coalescent +
distinct +
epiphytic;epiphytic;epiphytic +
barrel-shaped +  and spheric +