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Vascular Plants of California
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Mentzelia gracilenta


Higher Taxonomy
Family: LoasaceaeView DescriptionDichotomous Key
Common Name: LOASA FAMILY
Habit: Annual to subshrub; hairs needle-like, barbed, occasionally stinging. Leaf: alternate [opposite], generally +- pinnate-lobed; stipules 0. Inflorescence: cyme, raceme. Flower: bisexual, radial; sepals generally 5, generally persistent; petals generally 5, free or fused to each other or filament tube; stamens 5--many, filaments thread-like to flat, occasionally fused at base or in clusters; petal-like staminodes occasionally present; pistil 1, ovary inferior, chamber generally 1, placentas generally 3, parietal, style 1. Fruit: capsule or achene. Seed: 1--many.
Genera In Family: 18+ genera, 250 species: especially America (Africa, Pacific).
eFlora Treatment Author: Larry Hufford & Barry Prigge, except as noted
Scientific Editor: Douglas H. Goldman, Bruce G. Baldwin.
Genus: MentzeliaView DescriptionDichotomous Key


Common Name: BLAZING STAR
Habit: Annual to perennial herb, sometimes subshrub-like; hairs barbed to needle-like, not stinging; stems pale pink or generally +- white, branched or not. Leaf: linear to ovate, entire to pinnate-lobed; basal in rosettes, generally petioled; cauline generally sessile, +- reduced distally on stem. Inflorescence: generally cyme (or flower 1); bracts green to white-centered, margin green. Flower: sepals lanceolate to deltate, persistent; petals generally 5, free, white to yellow or orange; stamens generally many, +- free, generally unequal, inner filaments generally thread-like; outermost stamens opposite sepal lobes often modified, +- widened, or petal-like, with or without anthers or not; ovary generally cylindric, placentas generally 3, style thread-like, stigma 3-furrowed or -lobed. Fruit: capsule, cup-, barrel-, or urn-shaped to narrowly cylindric, occasionally curved. Seed: generally many, shape variable, sometimes winged.

eFlora Treatment Author: Joshua M. Brokaw, John J. Schenk, Barry Prigge & David Keil
Reference: Schenk & Hufford 2020 Syst Bot Monogr 110:1--230
Mentzelia gracilenta Torr. & A. Gray
NATIVE
Habit: Annual 3--60 cm. Stem: erect, hairy. Leaf: 2--13 cm, proximal lobed, distal entire to lobed. Inflorescence: bracts ovate to obovate, 3--12-toothed, base +- white. Flower: sepals 3--8 mm; petals (7)8--18 mm, obovate, yellow, base generally orange; stamens +- = style; style 5--11 mm. Fruit: erect to curved < 20°, generally 9--15(23) mm, 3--5 mm wide, cylindric to obconic; seed rows +- 3 distal to mid-fruit. Seed: 1.5--2.5 mm, irregular-angular, tan, dark mottled or not; seed coat cells generally domed, +- 1/2 tall as wide in age. Chromosomes: 2n=36.
Ecology: Generally unproductive substrates, including serpentine and calcium-rich soils, grassland to pine/oak woodland; Elevation: 200--1700 m. Bioregional Distribution: s SnFrB, SCoR, WTR, w SnGb. Flowering Time: Apr--May Note: Intergrades with Mentzelia ravenii, Mentzelia montana, Mentzelia veatchiana.
Jepson eFlora Author: Joshua M. Brokaw, John J. Schenk, Barry Prigge & David Keil
Reference: Schenk & Hufford 2020 Syst Bot Monogr 110:1--230
Index of California Plant Names (ICPN; linked via the Jepson Online Interchange)

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Citation for this treatment: Joshua M. Brokaw, John J. Schenk, Barry Prigge & David Keil 2023, Mentzelia gracilenta, in Jepson Flora Project (eds.) Jepson eFlora, Revision 12, https://ucjeps.berkeley.edu/eflora/eflora_display.php?tid=76712, accessed on April 19, 2024.

Citation for the whole project: Jepson Flora Project (eds.) 2024, Jepson eFlora, https://ucjeps.berkeley.edu/eflora/, accessed on April 19, 2024.

Mentzelia gracilenta
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©2009 Keir Morse
Mentzelia gracilenta
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©2016 Barry Breckling
Mentzelia gracilenta
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©2015 Neal Kramer
Mentzelia gracilenta
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©2003 Christopher L. Christie
Mentzelia gracilenta
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©2009 Keir Morse

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Geographic subdivisions for Mentzelia gracilenta:
s SnFrB, SCoR, WTR, w SnGb.
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map of distribution 1
(Note: any qualifiers in the taxon distribution description, such as 'northern', 'southern', 'adjacent' etc., are not reflected in the map above, and in some cases indication of a taxon in a subdivision is based on a single collection or author-verified occurence).





 

Data provided by the participants of the  Consortium of California Herbaria.
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All markers link to CCH specimen records. The original determination is shown in the popup window.
Blue markers indicate specimens that map to one of the expected Jepson geographic subdivisions (see left map). Purple markers indicate specimens collected from a garden, greenhouse, or other non-wild location.
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CCH collections by month

Duplicates counted once; synonyms included.
Species do not include records of infraspecific taxa, if there are more than 1 infraspecific taxon in CA.
Blue line denotes eFlora flowering time (fruiting time in some monocot genera).