Metastelma palmeri
Proc. Amer. Acad. Arts 18: 115. 1883.
Stems woody, not corky at base, glabrous. Leaves: 1 stipular colleter on each side of petiole, sometimes with 1 additional interpetiolar colleter; petiole 2–5 mm, sparsely puberulent; blade linear-lanceolate, elliptic, or lanceolate, 10–30 × 2–8 mm, chartaceous, faintly pinnately veined, base rounded to cuneate, with 2 laminar colleters, margins planar, apex acute to rounded, mucronulate, surfaces glabrous abaxially, pilosulous on midvein adaxially, margins sometimes sparsely pilosulous. Inflorescences shortly racemiform, 3–8-flowered; peduncle 0–2 mm, puberulent. Pedicels 1–2 mm, glabrous. Flowers: calyx lobes lanceolate to ovate, apices obtuse to acute, 1–1.5 mm, margins scarious, with 1 colleter per sinus; corolla cream to yellowish cream, campanulate, tube 0.5 mm, lobes erect with spreading tips, opening not obscured, linear, 1.5–2 mm, abaxially glabrous, adaxially densely, short-puberulent marginally and apically with opaque, matted, flattened hairs, densely hispid centrally with downward-pointing acicular, translucent hairs; corona segments united to base of anthers, laminar, lanceolate, 1 mm, slightly longer than gynostegium; gynostegium sessile; style apex convex. Follicles dark brown, 4–7 × 0.4–0.7 cm, apically acuminate, glabrous. Seeds 8–12, brown, flat, 4–6 × 2–3 mm, winged, with minute papillae forming ridges, chalazal margin erose; coma white, 2–3 cm.
Phenology: Flowering Apr–Oct; fruiting Jun–Oct.
Habitat: Valleys, plains, canyons, limestone, rocky, caliche, clay, or sandy soils, thorn scrub, oak-juniper woodland.
Elevation: 100–600 m.
Distribution
Tex., Mexico (Coahuila, Nuevo León, Tamaulipas).
Discussion
Metastelma palmeri overlaps in range with M. barbigerum in southern Texas. It is commonly encountered in the blackbrush thorn scrub of the Rio Grande valley and southwestern margin of the Edwards Plateau.
Selected References
None.