Mentzelia integra

PLANTS: Perennials. STEMS: glabrous or with sparse, diminutive trichomes, to 60 cm tall, producing branches along their entire length. LEAVES: to 14 cm long, to 2.5 cm wide, sessile, narrowly elliptic to lanceolate; margins entire or shallowly toothed to lobed; upper leaves often only slightly broadened at base and with clasping basal lobes. FLOWERS: pedicellate, subtended by 0-1(-2) linear-Ianceolate entire bracts; petals yellow, 10-20 mm long, 4-6 rom wide, with trichomes at apex only; staminodia (0)5, slightly smaller than the petals; outer 1-2 whorls of stamens commonly with broadened filaments; style 6-10 rom long; stigmatic papillae forming a slight tuft. CAPSULES: cup-shaped to broadly cylindric, (5-)9-15 mm long. SEEDS: horizontal, winged, oval to obovate, flattened; testa cells with curved to wavy adjoining walls, the surface walls with ca. 10 bumps. 2n = 20. NOTES: Commonly on sandy or gravelly soils, somtimes on cinders (Map 2A): n Coconino, n Mohave cos.; 350-1850 (-2150) m (1100-6000 (-7000) ft); Apr-Nov; s NV, sw UT. Similar to M. multiflora, but differing in chromosome number and seed surface characters. Best recognized by its often nearly glabrous stem and widely spaced flowers and broad fruits. REFERENCES: Christy, Charlotte M. 1998. Loasaceae. J. Ariz. - Nev. Acad. Sci. 30(2): 96.