Huaco, Runyon’s huaco

Runyonia longiflora Rose, Addisonia 7: 39, plate 244. 1922; Agave longiflora (Rose) G. D. Rowley; Polianthes runyonii Shinners

Rhizomes cylindrical. Leaves spreading, succulent, to 26.5 × 1.4 cm; blade green with darker green or brown narrowly elongate spots, channeled, lanceolate, margins with coarse, distantly spaced, cartilaginous teeth. Scape to 3 dm (–6 dm in cultivation). Inflorescences dense or lax, 0.8–2(–3.5) dm, 10–21-flowered. Flowers semierect, sessile; tepals white, maturing to rose; perianth tube narrowly funnelform, 2.3–3.6 cm; limb lobes recurved, 0.8–1.9 × 0.2–0.35 cm; filaments included, attached at top of tube; anthers nearly sessile; ovary 4–6 mm; style included, 1.4–2.8 cm; stigma white, deeply 3-lobed, lobes reflexed. Capsules depressed-globose, 1 × 1–1.3 cm. 2n = 60.

Flowering late summer--early fall. Clay slopes, dry gravelly hills or sandy prairies; of conservation concern; 0--100 m; Tex.; Mexico (Tamaulipas).