Mentzelia nitens |
Mentzelia multiflora |
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shining blazing star, Venus blazingstar |
Adonis blazingstar, Adonis stickleaf, desert stickleaf, many-flower western star |
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Habit | Plants candelabra-form, 5–20(–35) cm. | Plants biennial, candelabra-form. |
Stems | solitary, erect, straight; branches distal, distal longest, antrorse, upcurved; hairy. |
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Leaves | blade 35.9–125(–146) × 2.2–26.2 mm, widest intersinus distance 2.1–11.9(–14) mm, always on some leaves 4+ mm; proximal oblanceolate, lanceolate, or elliptic, margins pinnate, lobes 14–30, slightly antrorse or perpendicular to leaf axis, 1.5–4.6(–8.9) mm; distal lanceolate, base not clasping, margins pinnate, lobes 10–26, slightly antrorse or perpendicular to leaf axis, 1.3–9.5 mm; abaxial surface with simple grappling-hook, complex grappling-hook, and generally needlelike trichomes, adaxial surface with simple grappling-hook or needlelike trichomes. |
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Basal leaves | persisting; petiole present or absent; blade lanceolate to linear, margins usually deeply to shallowly lobed, rarely entire. |
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Cauline leaves | petiole absent; blade ovate-lanceolate to linear, to 15 cm, margins deeply to shallowly lobed or entire. |
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Bracts | green, lanceolate, 4.5–8.3 × 1.2–3.6 mm, width 1/5–1/2 length, not concealing capsule, margins entire. |
margins entire or toothed to pinnate. |
Flowers | sepals 3–8 mm; petals yellow to orange proximally, yellow distally, (7–)8–18 mm, apex rounded or acute apex; stamens 20+, 3–8 mm, filaments monomorphic, filiform, unlobed; styles 4–8 mm. |
petals light to golden yellow, (11.4–)13.8–24.4(–26.9) × 4–7.5 mm, apex rounded, glabrous abaxially; stamens light to golden yellow, 5 outermost petaloid, filaments narrowly spatulate, slightly clawed, (10.6–)12–21.7 × 2.1–5.1 mm, without anthers, second whorl with anthers; anthers straight after dehiscence, epidermis smooth; styles 7.7–15.8 mm. |
Capsules | clavate, 13–26 × 2–3.5 mm, axillary curved to 180° at maturity, usually inconspicuously longitudinally ribbed. |
cylindric, 11.2–24.7 × 5.6–8.7 mm, base tapering to rounded, not longitudinally ridged. |
Seeds | 15–40, in 2+ rows distal to mid fruit, tan, usually dark-mottled, usually irregularly polygonal, occasionally triangular prisms proximal to mid fruit, surface colliculate under 10x magnification; recurved flap over hilum usually present; seed coat cell outer periclinal wall domed, domes on seed edges less than 1/2 as tall as wide at maturity. |
coat anticlinal cell walls sinuous, papillae 34–48 per cell. |
2n | = 18. |
= 18. |
Mentzelia nitens |
Mentzelia multiflora |
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Phenology | Flowering Apr–Jun. | Flowering Jul–Sep. |
Habitat | Sandy washes, rocky slopes, desert scrub. | Dry roadsides, hillsides, washes, clayey, rocky, or sandy soils. |
Elevation | 400–2000 m. (1300–6600 ft.) | 1200–2100 m. (3900–6900 ft.) |
Distribution |
CA; NV
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CO; NE; NM; WY
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Discussion | Mentzelia nitens is similar to both M. eremophila and M. jonesii but exhibits little distributional overlap with either species. See 71. M. eremophila and 73. M. jonesii for discussion of similarities. Reports of M. nitens from Arizona are based on specimens treated here as M. jonesii. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Mentzelia multiflora has been considered one of the most widespread species in sect. Bartonia, a result of treating the species as a "garbage bin" for populations that lack features characteristic of more specialized species. The phylogenetic study by J. J. Schenk and L. Hufford (2011) showed that populations consistent with the type of M. multiflora are centered in the southern Rocky Mountains, especially along their eastern front, and the species notably does not occur in Arizona, California, Nevada, or Utah, in which it regularly has been described in regional floras. In the intermountain region, many specimens previously determined as M. multiflora are M. longiloba. In southeastern New Mexico and Texas, many specimens previously determined as M. multiflora are likely to be M. procera or M. longiloba var. chihuahuaensis. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Source | FNA vol. 12, p. 540. | FNA vol. 12, p. 523. |
Parent taxa | Loasaceae > Mentzelia > sect. Trachyphytum | Loasaceae > Mentzelia > sect. Bartonia |
Sibling taxa | ||
Synonyms | Bartonia multiflora, M. lutea, Nuttallia multiflora | |
Name authority | Greene: Fl. Francisc., 234. (1891) | (Nuttall) A. Gray: Mem. Amer. Acad. Arts, n. s. 4: 48. (1849) |
Web links |