Biol. Cent.-Amer., Bot. 3: 6. 1882.
Plants herbaceous, overall pubescence mixture of capitate-glandular hairs 0.2–0.3 mm, and white, capitate, shorter hairs 0.1–0.2 mm. Stems erect or ascending to decumbent, much-branched, 10–40 cm, puberulent to glabrate. Leaves yellowish green, petiolate, those of pair subequal; petiole 1–15 mm, puberulent; blade oval to ovatelanceolate or suborbiculate, 5–35 × 3–20 mm, base slightly unequal and obtuse to rounded or acute, margins crispate, apex apiculate and obtuse or infrequently acute, hirtellous to puberulent. Inflorescences solitary flowers, sessile or with pedicel to 1 mm; bracts linear-subulate, 2–8 mm, hirtellous to puberulent. Flowers: chasmogamous perianth 2.5–5 cm, puberulent to hirtellous, tube 1–1.5 mm diam., limbs 10–15 mm diam., stamens 5; cleistogamous perianth 3–8 mm, hirtellous, stamens 2 (–5). Fruits prominently 5-ribbed and deeply 5-sulcate, ribs broad, smooth, each terminating in hemispheric, glandular tubercle, tubercule oblong, truncate at both ends, 5–9 mm, puberulent.
Phenology: Flowering spring–fall.
Habitat: Various soils on calcareous substrates in grasslands or shrublands
Elevation: 200-1000 m
Tex., Mexico (Coahuila)
Of conservation concern.
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