Echinomastus erectocentrus

(J. M. Coulter) Britton & Rose

Cact. 3: 148. 1922.

Basionym: Echinocactus erectocentrus J. M. Coulter Contr. U.S. Natl. Herb. 3: 376. 1896
Synonyms: Neolloydia erectocentra (J. M. Coulter) L. D. Benson Sclerocactus erectocentrus (J. M. Coulter) N. P. Taylor
Treatment appears in FNA Volume 4. Treatment on page 194. Mentioned on page 193.

Stems 4–34.5  4–10 cm; ribs 18–21; areoles 8–19 mm apart along ribs; areolar glands present at least seasonally. Spines 13–19 per areole, purplish-pink to purple or nearly white with brown tips; radial spines 12–18 per areole; abaxial (shortest) radial spine 6–20 × 0.3–0.6 mm; adaxial and lateral (longest) radial spines 9–37 mm; central spines 1–3 (–4) per areole (usually absent from sexually immature plants), erect to ascending, 12–44 × 0.5–0.8 mm; longest adaxial central spine straight to curved upward, abaxial central spine 13–35 mm (absent in var. erectocentrus). Flowers 3.6–6 × 4–9 cm; inner tepals whitish to bright-rose-pink or lavender, basal portions olive-green to orangish brown, chestnut or maroon, (2–) 2.5–4.3 × 0.6–1.8 cm; stigma lobes red to brownish red, papillae red or green. Fruits dehiscent by vertical slits, ellipsoid-cylindric, 12–20 × 5–8+ mm. 2n = 22.

Discussion

Varieties 2 (2 in the flora).

The populations of Echinomastus erectocentrus north of Tucson, Arizona, are geographically, ecologically, and morphologically intermediate between the two named varieties. Echinomastus erectocentrus is replaced to the northwest by E. johnsonii; the two species are only weakly differentiated.

Selected References

None.

Key

1 Central spines relatively inconspicuous, erect, 1(-2) per areole; abaxial central spine 13-15(-29) mm; inner tepals whitish, pale lavender, or very pale pink, proximally olive green. Echinomastus erectocentrus var. erectoce
1 Central spines relatively conspicuous, ascending or abaxial spine porrect, (1-)2-3(-4) per areole; abaxial central spine 25-35 mm; inner tepals pale to bright rose-pink, proximally orangish brown, chestnut, maroon, or greenish brown Echinomastus erectocentrus var. acunensi
1.3 cm13 mm <br />0.013 m <br /> (3.5 cm35 mm <br />0.035 m <br />) +
0.9 cm9 mm <br />0.009 m <br /> (3.7 cm37 mm <br />0.037 m <br />) +
cushionlike +
circular to linear +
deciduous +  and persistent +
hourglass--shaped +
0.8 cm8 mm <br />0.008 m <br /> (1.9 cm19 mm <br />0.019 m <br />) +
Allan D. Zimmerman +  and Bruce D. Parfitt +
(J. M. Coulter) Britton & Rose +
hardened +
2 cm20 mm <br />0.02 m <br /> (2.5 cm25 mm <br />0.025 m <br />) +
olive-green +  and orangish brown chestnut or maroon +
2.5 cm25 mm <br />0.025 m <br /> (4.3 cm43 mm <br />0.043 m <br />) +
Echinocactus erectocentrus +
triangular +
curved +  and straight +
12mm +  and 44mm +
erect +  and ascending +
0.05 cm0.5 mm <br />5.0e-4 m <br /> (0.08 cm0.8 mm <br />8.0e-4 m <br />) +
proliferating +
flattened +  and cylindric +
mucilaginous +
firm +  and hard +
connected +
divided +  and notched +
Ariz. +  and Mexico +
not separating +
3.6 cm36 mm <br />0.036 m <br /> (6 cm60 mm <br />0.06 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 />) +
pink;dull;brown;pink;dull;brown;green +
persistent +, long +  and deciduous +
12mm;20mm +
ellipsoid-cylindric +
succulent +
0.5 cm5 mm <br />0.005 m <br /> (0.8 cm8 mm <br />0.008 m <br />) +
obscured +  and obliterated +
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 +
green +  and red +
deciduous +  and persistent +
mucilaginous +
ridgelike +  and nipple--shaped +
1 +  and 20 +
triangular +
arillate +  and strophiolate +
0.04 cm0.4 mm <br />4.0e-4 m <br /> (1.2 cm12 mm <br />0.012 m <br />) +
hemispheric;spheric +
purplish-pink +  and purple or nearly white +
curved +  and straight +
deciduous +  and persistent +
6mm +  and 20mm +
12 (?) +  and 18 (?) +
annulate-ridged +, hairlike +, daggerlike +, subulate +  and acicular +
0.3 cm3 mm <br />0.003 m <br /> (3.7 cm37 mm <br />0.037 m <br />) +
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 +
unsegmented +
3cm;20cm +
4 +  and 34.5 +
cylindric +, ovoid +  and spheric +
4 cm40 mm <br />0.04 m <br /> (10 cm100 mm <br />0.1 m <br />) +
succulent +
2cm;12cm +
red +  and brownish red +
tuberculate +
Neolloydia erectocentra +  and Sclerocactus erectocentrus +
adventitious +
tuberlike +
epipetric +  and epiphytic +
Echinomastus erectocentrus +
Echinomastus +
species +
undulate +  and entire +
dull +  and glossy +
epiphytic;epiphytic;epiphytic +
not deep-seated +
barrel-shaped +  and spheric +