Rhodora 46: 279. 1944.
Plants biennial but usually perennial; taproot stout. Stems erect to ascending, much-branched throughout, 10–30 cm, glabrous. Leaves: stipules lanceolate, 2–5 mm, apex acuminate to long-acuminate, entire; blade linear, 7–15(–19) × 0.4–0.8(–1) mm, leathery, apex subobtuse or minutely cuspidate, glabrous. Cymes terminating branchlets, 10–40+-flowered, repeatedly forked and diffuse, clusters 1–3 cm wide. Flowers 5-merous, ± short-campanulate, with enlarged hypanthium and calyx constricted proximally, 2.3–3.2 mm, hirtellous, glabrous distally; sepals red-brown, veins absent to obscure, narrowly oblong, 1.8–2.3 mm, leathery to rigid, margins translucent, 0.05–0.1 mm wide, scarious, apex terminated by awn, hood conspicuously rounded, awn divergently spreading, 1–1.5(–2) mm, ± broadly conic in proximal 1/3 with yellowish, glabrous spine; staminodes filiform, 0.7–0.9 mm; style 1, cleft in distal 1/5, 0.6–1.3 mm. Utricles ovoid, 1.2–1.5 mm, minutely papillose distally.
Phenology: Flowering summer–fall.
Habitat: Mountain tops, rocky slopes and ledges, gravel beds of mountain streams
Elevation: ca 1200 m
Tex., Mexico (Coahuila).