Mentzelia veatchiana |
Mentzelia hualapaiensis |
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Veatch's blazing star, white-stem blazingstar, white-stem stick-leaf |
Hualapai blazingstar |
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Habit | Plants candelabra-form, (5–)20–50 cm. | 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. |
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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. |
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Basal leaves | persisting; petiole present or absent; blade linear-lanceolate, margins deeply to shallowly lobed. |
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Cauline leaves | petiole absent; blade ovate-lanceolate to lanceolate, to 17 cm, margins usually deeply lobed to dentate, rarely entire. |
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Bracts | usually green with prominent white base usually conspicuously extending outwards from midvein, rarely green, usually ovate, rarely lanceolate, 3.3–6.2 × 1.5–3.2 mm, width 1/4–7/8 length, not concealing capsule, margins usually 3–7-lobed, rarely entire. |
margins entire. |
Flowers | sepals 2–5 mm; petals red to orange proximally, orange to yellow distally, 4–7(–10) mm, apex retuse; stamens 20+, 3–7 mm, filaments monomorphic, filiform, unlobed; styles (3–)3.5–6 mm. |
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 | clavate, 8–28 × 2–4 mm, axillary curved to 70° at maturity, usually inconspicuously longitudinally ribbed. |
cup-shaped, 4.9–10.3 × 4.6–8.6 mm, base rounded, not longitudinally ridged. |
Seeds | 15–35, in 2+ rows distal to mid fruit, tan, dark-mottled, usually irregularly polygonal, occasionally triangular prisms proximal to mid fruit, surface tuberculate under 10x magnification; recurved flap over hilum absent; seed coat cell outer periclinal wall domed, domes on seed edges more than or equal to 1/2 as tall as wide at maturity. |
coat anticlinal cell walls straight to slightly wavy, papillae 8–14 per cell. |
2n | = 54. |
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Mentzelia veatchiana |
Mentzelia hualapaiensis |
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Phenology | Flowering Mar–Jun. | Flowering Mar–Jun(–Sep). |
Habitat | Loamy to sandy soils, grasslands, desert scrub, oak-pine woodlands. | Rocky desert scrub, gravelly canyon bottoms, steep travertine, shaley slopes associated with Muav limestone formations. |
Elevation | 200–2500 m. [700–8200 ft.] | 400–1400 m. [1300–4600 ft.] |
Distribution |
AZ; CA; NV; OR
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AZ |
Discussion | Mentzelia veatchiana is the most common and widely distributed hexaploid species in sect. Trachyphytum. It exhibits considerable morphological variation and can be difficult to distinguish from M. montana in northern California. Like the larger-flowered M. pectinata, M. veatchiana has interfertile populations with petal colors ranging from orange to yellow (J. E. Zavortink 1966). When bearing orange petals, M. veatchiana is easily distinguished from other species. Reports of M. veatchiana from Utah are based on specimens treated here as M. montana. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Mentzelia hualapaiensis is distributed in Coconino and Mohave counties along the Grand Canyon and its side canyons between the Upper and Lower Granite Gorge. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Source | FNA vol. 12, p. 543. | FNA vol. 12, p. 502. |
Parent taxa | ||
Sibling taxa | ||
Synonyms | M. albicaulis var. veatchiana | |
Name authority | Kellogg: Proc. Calif. Acad. Sci. 2: 99, fig. 28. (1863) | J. J. Schenk: W. C. Hodgson & L. Hufford, Brittonia 62: 1, figs. 1, 2A,C–E. (2010) |
Web links |