Mentzelia marginata

(Osterhout) H. J. Thompson & Prigge

Great Basin Naturalist, 46: 549. 1986.

Common names: Colorado blazingstar
Endemic
Basionym: Nuttallia marginata Osterhout Bull. Torrey Bot. Club 49: 183. 1922
Treatment appears in FNA Volume 12. Treatment on page 506. Mentioned on page 499.

Plants winter-annual or biennial, candelabra-form. Stems solitary, erect, straight; branches mostly distal, proximal longer than distal, all usually extending to near the distal end of plant, antrorse, straight; hairy. Leaves: blade 22–115 × 2.8–10.9 (–17.2) mm, widest intersinus distance 2.2–7 (–9) mm; proximal oblanceolate, elliptic, or lanceolate, margins dentate, teeth 10–24 (–38), perpendicular to leaf axis, 0.5–4 mm; distal elliptic to lanceolate, base not clasping, margins dentate, teeth 8–20, perpendicular to leaf axis, 0.3–5.6 mm; abaxial surface with simple grappling-hook, complex grappling-hook, and usually with needlelike trichomes, adaxial surface with simple grappling-hook and needlelike trichomes. Bracts: margins entire. Flowers: petals golden yellow, 8–14.4 × 2.1–3.9 mm, apex acute, hairy abaxially; stamens golden yellow, 5 outermost petaloid, filaments narrowly spatulate, slightly clawed, 5.5–11.1 × 1.2–2.9 mm, with anthers, second whorl with anthers; anthers straight after dehiscence, epidermis papillate; styles 5.3–10 mm. Capsules cylindric, 7–14.6 × 3.5–6.7 mm, base tapering, not longitudinally ridged. Seeds: coat anticlinal cell-walls straight to slightly wavy, papillae 4–10 per cell. 2n = 20.


Phenology: Flowering May–Aug.
Habitat: Steep roadside banks, steep cliffs.
Elevation: 1500–2000 m.

Discussion

Mentzelia marginata occurs on the western edge of Colorado in Delta, Garfield, Mesa, and Montrose counties. Reports of this species from Utah are based on specimens treated here as M. cronquistii.

Selected References

None.

Lower Taxa

None.

No values specified."not elongating" is not a number.

... more about "Mentzelia marginata"
petaloid +  and heteromorphic +
0.55 cm5.5 mm <br />0.0055 m <br /> (1.11 cm11.1 mm <br />0.0111 m <br />) +
clawed +  and spatulate +
0.12 cm1.2 mm <br />0.0012 m <br /> (0.29 cm2.9 mm <br />0.0029 m <br />) +
John J. Schenk +  and Larry Hufford +
(Osterhout) H. J. Thompson & Prigge +
ridged +  and tapering +
Nuttallia marginata +
0.7 cm7 mm <br />0.007 m <br /> (0.9 cm9 mm <br />0.009 m <br />) +
1.09 cm10.9 mm <br />0.0109 m <br /> (1.72 cm17.2 mm <br />0.0172 m <br />) +
2.2 cm22 mm <br />0.022 m <br /> (11.5 cm115 mm <br />0.115 m <br />) +
unlobed;lobed;orbiculate;obovate;unlobed;lobed;orbiculate;obovate;unlobed;lobed;orbiculate;obovate;oblanceolate;spatulate;linear;lanceolate;elliptic;ovate;cordate;deltate;hastate +
0.22 cm2.2 mm <br />0.0022 m <br /> (0.7 cm7 mm <br />0.007 m <br />) +
0.7 cm7 mm <br />0.007 m <br /> (1.46 cm14.6 mm <br />0.0146 m <br />) +
cylindric +
0.35 cm3.5 mm <br />0.0035 m <br /> (0.67 cm6.7 mm <br />0.0067 m <br />) +
Colorado blazingstar +
elliptic;lanceolate +
1500–2000 m. +
curved +  and straight +
s--shaped +, clavate +, urceolate +, ovoid +, cylindric +, subcylindric +, lingulate +  and cup-shaped +
simple +  and complex +
Steep roadside banks, steep cliffs. +
free +  and adnate +
unlobed +  and filiform +
cauline +  and basal +
entire +  and dentate +
apical +, subapical +  and inferior +
perpendicular +  and oriented +
inconspicuous +
golden yellow +
connate +  and distinct +
8mm;14.4mm +
spreading +  and erect +
hairy +  and glabrous +
obovate +, oblanceolate +, elliptic +, ovate +  and spatulate +
0.21 cm2.1 mm <br />0.0021 m <br /> (0.39 cm3.9 mm <br />0.0039 m <br />) +
Flowering May–Aug. +
0 cm0 mm <br />0 m <br /> (1 cm10 mm <br />0.01 m <br />) +
Great Basin Naturalist, +
flattened +  and ovoid +
0.05 cm0.5 mm <br />5.0e-4 m <br /> (0.45 cm4.5 mm <br />0.0045 m <br />) +
persistent +
lanceolate +  and narrowly ovate +
golden yellow +
adnate +, free +  and distinct +
included +  and exserted +
straight +
papillate +
3-lobed +  and lingulate +
0.53 cm5.3 mm <br />0.0053 m <br /> (1 cm10 mm <br />0.01 m <br />) +
Mentzelia marginata +
Mentzelia sect. Bartonia +
species +
perpendicular +
0.03 cm0.3 mm <br />3.0e-4 m <br /> (0.56 cm5.6 mm <br />0.0056 m <br />) +
dendritic +  and unbranched +
sinuous +  and straight +
biennial +  and winter-annual +