Hamatocactus bicolor

(Terán & Berlandier) I. M. Johnston

Contr. Gray Herb. 70: 88. 1924.

Common names: Twisted-rib cactus
Illustrated
Basionym: Cactus bicolor Terán & Berlandier in J. L. Berlandier, Mem. Comis. Limites, 4. 1832
Synonyms: Ferocactus setispinus (Engelma nn) L. D. Benson Hamatocactus setispinus (Englemann) Britton & Rose Thelocactus setispinus (Engelmann) E. F. Anderson
Treatment appears in FNA Volume 4. Treatment on page 219. Mentioned on page 208, 209.

Spines: central spine yellowish, becoming ashy gray or reddish-brown, 1–3.8 cm, minutely scabrous (use 30× lens). Flowers yellow with red centers, leaving obvious, concave abscission scars after fall of flower or fruit; proximal outer tepals obtuse or with broad ± auriculate distal portions; distal ones minutely fringed, acute; inner tepals oblanceolate; filaments reddish, pale-yellow, or whitish, collectively spiraled around style; ovary 8–13 mm diam. Fruits displaced away from stem apex by apical growth subsequent to flowering. 2n = 22.


Phenology: Flowering spring–early fall.
Habitat: Grasslands, shrublands, especially mesquite thickets, heavy soils
Elevation: 0-300 m

Distribution

V4 410-distribution-map.gif

Tex., Mexico (Coahuila), Mexico (Nuevo León), Mexico (Tamaulipas)

Discussion

Hamatocactus bicolor is taxonomically isolated in the flora. It is perhaps most similar to Thelocactus bicolor, but H. bicolor is dramatically different in its juicy, scarlet fruits, yellow flowers, very narrowly and sharply ribbed stem surface, and hooked central spines. Hamatocactus bicolor is superficially similar to Ferocactus hamatacanthus var. sinuatus, which is larger and green-fruited with pitted seed coat and much larger yellow flowers lacking red centers. Glandulicactus uncinatus has hooked radial spines, rounded birbs, and small, maroon flowers.

Selected References

None.

Lower Taxa

None.

"elongated" is not a number."broad" is not a number.

... more about "Hamatocactus bicolor"
cushionlike +
darker +  and golden +
peglike +  and cylindric +
deciduous +  and persistent +
elliptic +  and ovate +
Allan D. Zimmerman +  and Bruce D. Parfitt +
(Terán & Berlandier) I. M. Johnston +
hardened +
Cactus bicolor +
triangular +
reddish-brown +, ashy gray +  and yellowish +
terete +  and hooked +
1 cm10 mm <br />0.01 m <br /> (3.8 cm38 mm <br />0.038 m <br />) +
proliferating +
flattened +  and cylindric +
Twisted-rib cactus +
not mucilaginous +
not interrupted +
undulate +, sharp +  and sinuate +
Tex. +, Mexico (Coahuila) +, Mexico (Nuevo León) +  and Mexico (Tamaulipas) +
0-300 m +
not separating +
whitish +, pale-yellow +  and reddish +
3.7 cm37 mm <br />0.037 m <br /> (7 cm70 mm <br />0.07 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 />) +
dehiscent +  and indehiscent +
persistent +, long +  and deciduous +
nearly +  and spheric +
0.8 cm8 mm <br />0.008 m <br /> (1.3 cm13 mm <br />0.013 m <br />) +
Grasslands, shrublands, especially mesquite thickets, heavy soils +
2 cm20 mm <br />0.02 m <br /> (2.5 cm25 mm <br />0.025 m <br />) +
oblanceolate +
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 +
1.1 cm11 mm <br />0.011 m <br /> (3.2 cm32 mm <br />0.032 m <br />) +
lacerate +, toothed +  and entire +
0.8 cm8 mm <br />0.008 m <br /> (1.3 cm13 mm <br />0.013 m <br />) +
deciduous +  and persistent +
Flowering spring–early fall. +
not mucilaginous +
ridgelike +  and nipple--shaped +
acute +, fringed +, with broad more or less auriculate distal portions +  and obtuse +
Contr. Gray Herb. +
slender +
spineless +  and naked +
fringed +
abscission +
concave +
arillate +  and strophiolate +
0.04 cm0.4 mm <br />4.0e-4 m <br /> (1.2 cm12 mm <br />0.012 m <br />) +
0.1 cm1 mm <br />0.001 m <br /> (0.14 cm1.4 mm <br />0.0014 m <br />) +
papillate +
obovoid +
0.08 cm0.8 mm <br />8.0e-4 m <br /> (0.1 cm1 mm <br />0.001 m <br />) +
Illustrated +
reddish-brown +, whitish +  and not yellowish +
curved +  and straight +
deciduous +  and persistent +
10 (?) +  and 19 (?) +
acicular +
hard +  and rigid +
decurrent +
unsegmented +
3.6cm;12cm +
ovoid +  and cylindric +
succulent +
4.5cm;12cm +
pale-yellow +  and orangish +
tuberculate +
Ferocactus setispinus +, Hamatocactus setispinus +  and Thelocactus setispinus +
adventitious +
tuberlike +
epipetric +  and epiphytic +
Hamatocactus bicolor +
Hamatocactus +
species +
dull +  and glossy +
branched +  and unbranched +
epiphytic;epiphytic;epiphytic +
not deep-seated +
barrel-shaped +  and spheric +