Gutierrezia sphaerocephala

A. Gray

Mem. Amer. Acad. Arts, n. s. 4: 73. 1849.

Common names: Round-leaf snakeweed
Synonyms: Gutierrezia eriocarpa A. Gray Xanthocephalum sphaerocephalum (A. Gray) Shinners Xanthocephalum sphaerocephalum var. eriocarpum (A. Gray) Shinners
Treatment appears in FNA Volume 20. Treatment on page 92. Mentioned on page 89.

Annuals, 20–50 cm. Stems minutely, prominently, often sparsely, papillate-scabrous (hairs triangular or deltate to lanceolate, less than 0.1 mm). Leaves: proximal usually absent at flowering; cauline blades 1-nerved, linear, 0.5–1.2 mm wide, little reduced distally. Heads in loose arrays. Involucres campanulate, 2.5–5 mm diam. Phyllary apices flat. Ray-florets 10–15; corollas yellow, 3–5.5 mm. Disc-florets 18–37. Cypselae 0.9–1.2 (–1.4) mm, faces without oil cavities, densely strigoso-sericeous in rows (hairs appressed to spreading, apices clavate); pappi of 1 series of narrowly triangular or narrowly oblong scales 0.2–1 mm (distinct or basally connate 1/4–3/4 their lengths, usually shorter in rays). 2n = 8 (10).


Phenology: Flowering (Feb–)May–Dec.
Habitat: Grasslands, roadsides, lake edges, alkaline flats with Atriplex, oak-pine-juniper woodlands, often over gypsum or limestone
Elevation: (200–)1300–2000 m

Distribution

V20-176-distribution-map.gif

Ariz., N.Mex., Tex., Mexico (Chihuahua), Mexico (Coahuila), Mexico (Durango), Mexico (Nuevo León), Mexico (San Luis Potosí), Mexico (Tamaulipas), Mexico (Zacatecas)

Discussion

Selected References

None.

Lower Taxa

None.

"[" is not declared as a valid unit of measurement for this property."]" is not declared as a valid unit of measurement for this property.

hirtellous +, hispidulous +  and glabrous +
not tailed +, rounded +  and obtuse +
distinct +
subequal +
scarious +
usually triangular +  and linear +
usually deltate +  and lanceolate +
spiciform +, racemiform +, paniculiform +  and corymbiform +
indeterminate +  and determinate +
Guy L. Nesom +
A. Gray +
decurrent +
white-indurate +
compound +  and simple +
linear;lanceolate or spatulate +
rugulose +  and muricate +
barbellulate +  and barbellate +
Round-leaf snakeweed +
not 2-lipped +  and actinomorphic +
0.3 cm3 mm <br />0.003 m <br /> (0.55 cm5.5 mm <br />0.0055 m <br />) +
beaked +, 2-ribbed +  and 5-ribbed +
0.12 cm1.2 mm <br />0.0012 m <br /> (0.14 cm1.4 mm <br />0.0014 m <br />) +
not compressed +, cylindric +  and clavate +
fertile +  and bisexual +
fertile +  and bisexual +
Ariz. +, N.Mex. +, Tex. +, Mexico (Chihuahua) +, Mexico (Coahuila) +, Mexico (Durango) +, Mexico (Nuevo León) +, Mexico (San Luis Potosí) +, Mexico (Tamaulipas) +  and Mexico (Zacatecas) +
(200–)1300–2000 m +
resinous +
gland-dotted +
strigoso-sericeous +
pistillate +, staminate +  and neuter +
winged +  and beaked +
dispersed +
Grasslands, roadsides, lake edges, alkaline flats with Atriplex, oak-pine-juniper woodlands, often over gypsum or limestone +
indeterminate +
heterogamous +  and homogamous +
each +  and sessile +
0.25 cm2.5 mm <br />0.0025 m <br /> (0.5 cm5 mm <br />0.005 m <br />) +
campanulate +
petiolate +  and sessile +
cauline +  and basal +
short-deltate +
2-carpellate +
erose-margined +
persistent +
of 5-10 whitish +  and coroniform +
Flowering (Feb–)May–Dec. +
3-nerved +  and 1-nerved +
ovate +  and lanceolate +
Mem. Amer. Acad. Arts, n. s. +
bearing subulate enations +, hairy +  and bristly +
0.02 cm0.2 mm <br />2.0e-4 m <br /> (0.1 cm1 mm <br />0.001 m <br />) +
oblong +  and triangular +
exalbuminous +
erect +  and ascending +
papillate-scabrous +
appendaged +  and truncate +
papillate +  and smooth +
Gutierrezia eriocarpa +, Xanthocephalum sphaerocephalum +  and Xanthocephalum sphaerocephalum var. eriocarpum +
Gutierrezia sphaerocephala +
Gutierrezia +
species +
150 cm1,500 mm <br />1.5 m <br /> (200 cm2,000 mm <br />2 m <br />) +
20 cm200 mm <br />0.2 m <br /> (50 cm500 mm <br />0.5 m <br />) +