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, Coahuila, Durango, Nuevo León, San Luis Potosí, Tamaulipas, Zacatecas).

Discussion

Selected References

None.

Lower Taxa

None.
Guy L. Nesom +
A. Gray +
Round-leaf snakeweed +
Ariz. +, N.Mex. +, Tex. +, Mexico (Chihuahua +, Coahuila +, Durango +, Nuevo León +, San Luis Potosí +, Tamaulipas +  and Zacatecas). +
(200–)1300–2000 m +
Grasslands, roadsides, lake edges, alkaline flats with Atriplex, oak-pine-juniper woodlands, often over gypsum or limestone +
Flowering (Feb–)May–Dec. +
Mem. Amer. Acad. Arts, n. s. +
Gutierrezia eriocarpa +, Xanthocephalum sphaerocephalum +  and Xanthocephalum sphaerocephalum var. eriocarpum +
Gutierrezia sphaerocephala +
Gutierrezia +
species +