Cirsium texanum

Buckley

Proc. Acad. Nat. Sci. Philadelphia 13: 460. 1862.

Common names: Texas or Texas purple or southern thistle
Synonyms: Cirsium austrinum (Small) E. D. Schulz Cirsium helleri (Small) Cory Cirsium texanum var. stenolepis Shinners
Treatment appears in FNA Volume 19. Treatment on page 119. Mentioned on page 98.

Annuals or biennials, 20–200 cm; taprooted. Stems usually single, erect, tomentose to ± glabrate; branches 0–many, usually restricted to distal part, ascending. Leaves: blades oblong to elliptic, 7–30 × 2–12 cm, unlobed and merely spinulose to irregularly dentate or shallowly to deeply pinnatifid, lobes ± triangular, separated by narrow to wide sinuses, sometimes coarsely dentate or lobed proximally, obtuse to acute, main spines slender to stout, 1–5 mm, abaxial faces arachnoid tomentose, adaxial glabrous or thinly arachnoid; basal often absent at flowering, petioles slender, ± winged; cauline progressively reduced, proximal petiolate, mid and distal broadly sessile, bases ± auriculate-clasping or decurrent 1–3 cm; distalmost linear to lanceolate, bractlike, irregularly dentate or shallowly lobed. Heads 1–many, in openly paniculiform arrays. Peduncles slender, 3–30 cm (not overtopped by crowded distal leaves). Involucres ovoid to hemispheric, 1.5–2 × 1.5–2 cm, thinly arachnoid, glabrate. Phyllaries in 8–10 series, imbricate, green, lanceolate (outer) to linear (inner), abaxial faces with prominent glutinous ridge; outer and middle appressed, bodies entire, acute, spines spreading, slender, 1–5 mm; apices of inner often flexuous, flat, scabrid-ciliolate, acuminate. Corollas white to pink-purple, 20–25 mm, tubes 7–10 mm, throats 6–8 mm (noticeably wider than tubes), lobes 4–7 mm; style tips 3–4 mm. Cypselae brown, 3–5 mm, apical collars not differentiated; pappi 15–16 mm. 2n = 22, 23, 24.


Phenology: Flowering spring–summer (Apr–Jul).
Habitat: Roadsides, pastures, fields, shrub-tree savannas
Elevation: 0–1000 m

Distribution

V19-73-distribution-map.gif

Ark., La., Mo., N.Mex., Okla., Tex., Mexico (Coahuila), Mexico (Durango), Mexico (Nuevo León), Mexico (San Luis Potosí), Mexico (Tamaulipas)

Discussion

Cirsium texanum ranges from the Chihuahuan Desert regions of trans-Pecos Texas and adjacent southeastern New Mexico across the plains of Texas and southern Oklahoma to southwestern Arkansas and southwestern Louisiana and south into north-central Mexico. D. S. Correll and M. C. Johnston (1970) suggested hybridization between Cirsium texanum and C. undulatum to explain anomalous specimens in the Edwards Plateau and trans-Pecos regions of western Texas.

Selected References

None.

Lower Taxa

None.

"fine" is not a number."narrow" is not a number. "wide" is not a number.

... more about "Cirsium texanum"
24 +, 23 +  and 22 +
tomentose +  and arachnoid +
arachnoid +  and glabrous +
short-tailed +
spineless +  and twisted +
dentate +, entire +  and spine-tipped +
erect +  and spreading +
innermost +
scarious +
not differentiated +
paniculiform +
indeterminate +  and determinate +
David J. Keil +
Buckley +
auriculate-clasping +
decurrent +
1 cm10 mm <br />0.01 m <br /> (3 cm30 mm <br />0.03 m <br />) +
Asteraceae tribe Cynareae +
compound +  and simple +
7 cm70 mm <br />0.07 m <br /> (30 cm300 mm <br />0.3 m <br />) +
irregularly dentate or;shallowly deeply pinnatifid +
2cm;12cm +
10-nerved or 20-nerved +  and rugose +
tawny +  and white +
Texas or Texas purple or southern thistle +
actinomorphic +
white +  and pink-purple +
2 cm20 mm <br />0.02 m <br /> (2.5 cm25 mm <br />0.025 m <br />) +
compressed +  and ovoid +
fertile +  and bisexual +
linear +  and lanceolate bractlike irregularly dentate or shallowly lobed +
Ark. +, La. +, Mo. +, N.Mex. +, Okla. +, Tex. +, Mexico (Coahuila) +, Mexico (Durango) +, Mexico (Nuevo León) +, Mexico (San Luis Potosí) +  and Mexico (Tamaulipas) +
0–1000 m +
gray-canescent +  and glabrous +
pistillate +, staminate +  and neuter +
winged +  and beaked +
dispersed +
Roadsides, pastures, fields, shrub-tree savannas +
indeterminate +
each +  and sessile +
1.5 cm15 mm <br />0.015 m <br /> (2 cm20 mm <br />0.02 m <br />) +
glabrate +  and arachnoid +
ovoid;hemispheric +
1.5 cm15 mm <br />0.015 m <br /> (2 cm20 mm <br />0.02 m <br />) +
sessile +  and petiolate +
cauline +  and basal +
bristle-tipped +
obtuse +  and acute +
0.1 cm1 mm <br />0.001 m <br /> (0.5 cm5 mm <br />0.005 m <br />) +
entire +  and dentate +
usually lobed +  and dissected +
2-carpellate +
persistent +
1.5 cm15 mm <br />0.015 m <br /> (1.6 cm16 mm <br />0.016 m <br />) +
3 cm30 mm <br />0.03 m <br /> (30 cm300 mm <br />0.3 m <br />) +
Flowering spring–summer (Apr–Jul). +
middle +  and outer +
weakly to strongly +
papillate +  and smooth +
Proc. Acad. Nat. Sci. Philadelphia +
bearing subulate enations +, hairy +  and bristly +
flat;convex +
glutinous +
tawny;white +
setiform +  and plumose +
exalbuminous +
subequal +
0.1 cm1 mm <br />0.001 m <br /> (0.5 cm5 mm <br />0.005 m <br />) +
spiny-winged +, simple +  and branched +
appendaged +  and truncate +
dilated +  and swollen +
enlarged +
0.3 cm3 mm <br />0.003 m <br /> (0.4 cm4 mm <br />0.004 m <br />) +
Cirsium austrinum +, Cirsium helleri +  and Cirsium texanum var. stenolepis +
Cirsium texanum +
species +
cylindric +
expanded +
0.6 cm6 mm <br />0.006 m <br /> (0.8 cm8 mm <br />0.008 m <br />) +
bristly-dentate to coarsely +
slender +
0.7 cm7 mm <br />0.007 m <br /> (1 cm10 mm <br />0.01 m <br />) +
biennial +  and annual +
20 cm200 mm <br />0.2 m <br /> (200 cm2,000 mm <br />2 m <br />) +
tree +, vine +, shrub +  and subshrub +