Viguiera stenoloba

Shrubs, 50-150 cm. Leaves opposite or alternate; sessile or subsessile; blades ovate (and shallowly to deeply lobed, lobes 3-9, ± linear) or linear, 1.5-10.8 × 1-9 cm, ultimate margins entire (revolute), faces: abaxial loosely to densely strigillose (canescent) and gland-dotted, adaxial densely strigose to glabrate. Heads usually borne singly. Peduncles 2-5 cm. Involucres 5-12 × 7-9 mm. Phyllaries abruptly narrowed to acuminate or spatulate (phyllary bases broad, indurate, apices herbaceous). Paleae (oblong-rectangular) 4-5 mm, apices abruptly acuminate. Ray florets 13-18; tubes 0.9-1.1 mm, laminae 7-12 mm. Disc florets 100+; corollas 3.3-4.2 mm. Cypselae 2-3 mm, glabrous; pappi 0. 2n = 34, 68.

Flowering May-Sep. Tamaulipan and Chihuahuan Desert scrub; 800-1900 m; N.Mex., Tex.; Mexico (Chihuahua, Coahuila, Durango, Nuevo León, San Luis Potosí, Tamaulipas, Zacatecas).

Viguiera stenoloba is a dominant shrub in some places in the trans-Pecos region of Texas. M. L. Butterwick (1975) suggested that the species is separable into two varieties; those have never received formal taxonomic recognition.