Oenothera suffulta (Engelmann ex A. Gray) W. L. Wagner & Hoch, Syst. Bot. Monogr. 83: 214. 2007.

Wagner, Warren L., Krakos, Kyra N. & Hoch, Peter C., 2013, Taxonomic changes in Oenothera sections Gaura and Calylophus (Onagraceae), PhytoKeys 28, pp. 61-72 : 64-65

2. Oenothera suffulta (Engelmann ex A. Gray) W. L. Wagner & Hoch, Syst. Bot. Monogr. 83: 214. 2007.

Basionym.

Gaura suffulta Engelmann ex A. Gray, Bost. J. Nat. Hist. 6: 190. 1850.

Type.

United States. Texas: Comal County, New Braunfels, May 1847, F. Lindheimer 611 (Lectotype, designated by Raven & Gregory, 1972 [1973]: 80, GH- 00054125!; Isolectotypes: BM, F!, GH [3]!, K [2]!, LE, M!, MO [3]!, NY!, PH, TEX!,, US[2]!, YU!).

Annual from a stout taproot, moderately branched from the base, 25-120 cm tall, villous proximally, the leaves subglabrous or sparsely villous along the veins and around the margins, becoming glabrous distally or rarely sparsely villous on the bracts. Leaves: rosette leaves 7-11 × 0.1-2.3 cm, lyrate, gradually narrowed to the petiole; cauline leaves 1-9.5 × 0.1-2.3, narrowly lanceolate to linear, margin sinuate-dentate, undulate, subsessile. Flowers 4-merous, opening at sunset; floral tube 6.5-14 mm; sepals 11-21 mm; petals 10-15 mm; staminal filaments 6-9 mm, anthers 2-6 mm, pollen 90-100% fertile; style 16-32 mm. Capsule indehiscent, 4.5-8 × 2-5 mm, nut-like, hard, woody, not reflexed, the body ellipsoid or ovoid, broadly winged on the angles and deeply furrowed between the angles, without prominent lower corners or projections of the wings at or above the middle; stipe 0-1 mm long. Seeds (1-)2-4, 2-2.5 mm, ovoid, usually flattened on one or several sides by crowding in the fruit, yellowish to light brown. Gametic chromosome number: n = 7. Self-incompatible.

Phenology and distribution.

Flowering from April to June. Common in western Texas, but rare elsewhere throughout the state and absent in the Trans-Pecos; southern Oklahoma, east to Tulsa, Okfuskee, and Coal counties, and in Woodward County, in open, sandy places; 10-1010 m.