1. Mentzelia hualapaiensis J. J. Schenk, W. C. Hodgson & L. Hufford, Brittonia. 62: 1, figs. 1, 2A,C–E. 2010.
Hualapai blazingstar Hualapai blazingstar
Plants perennial, bushlike, with subterranean caudices. Stems multiple, erect, zigzag or straight; branches distal or along entire stem, distal longest or all ± equal, antrorse, upcurved; hairy. Leaves: blade 17–94 × 12–32 mm, widest intersinus distance 9.5–29 mm; proximal broadly spatulate to elliptic, margins serrate, teeth 6–12, slightly antrorse or perpendicular to leaf axis, 0.4–1.5 mm; distal broadly spatulate, elliptic, or obovate, base not clasping, margins serrate, teeth 8–10, slightly antrorse or perpendicular to leaf axis, 1–3.6 mm; abaxial surface with complex grappling-hook and occasionally with simple grappling-hook and needlelike trichomes, adaxial surface with needlelike trichomes. Bracts: margins entire. Flowers: petals white to light yellow, 9.4–17.4(–20) × 1.7–4.3 mm, apex acute to rounded, glabrous abaxially; stamens white to light yellow, 5 outermost petaloid, filaments narrowly spatulate, slightly clawed, 8.5–18 × 1–1.3(–2.9) mm, without anthers, second whorl with anthers; anthers straight after dehiscence, epidermis papillate; styles 5.8–9 mm. Capsules cup-shaped, 4.9–10.3 × 4.6–8.6 mm, base rounded, not longitudinally ridged. Seeds: coat anticlinal cell walls straight to slightly wavy, papillae 8–14 per cell.
Flowering Mar–Jun(–Sep). Rocky desert scrub, gravelly canyon bottoms, steep travertine, shaley slopes associated with Muav limestone formations; 400–1400 m; Ariz.
Mentzelia hualapaiensis is distributed in Coconino and Mohave counties along the Grand Canyon and its side canyons between the Upper and Lower Granite Gorge.