Jepson Flora Project: Jepson Interchange    

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Jepson Interchange (more information)
©Copyright 1993 by the Regents of the University of California

  • Up-to-date information about California vascular plants is available from the Jepson eFlora.



Barry Prigge

Annual to shrub; hairs needle-like, stinging, or rough
Leaves alternate in CA, generally ± pinnately lobed; stipules 0
Inflorescence various
Flower bisexual, radial; sepals generally 5, generally persistent in fruit; petals generally 5, free or fused to each other or to filament tube; stamens 5–many, filaments thread-like to flat, sometimes fused at base or in clusters; petal-like staminodes sometimes present; pistil 1, ovary inferior, chamber generally 1, placentas generally 3, parietal, style 1
Fruit: generally capsule (utricle)
Seeds 1–many
Genera in family: 15 genera, ± 200 species: especially Am (Africa, Pacific)
Reference: [Ernst & Thompson 1963 J Arnold Arbor 44:138–142]



Annual to shrub; hairs generally barbed-rough (smooth)
Leaf linear to ovate, generally ± lobed; basal in rosettes, generally petioled; cauline generally sessile, ± reduced upward
Inflorescence: generally cyme (or flower 1); bract generally 1 per flower, generally green
Flower: sepals lanceolate to deltate, generally persistent; petals 5, free, generally yellow; stamens generally many, ± free, generally unequal, inner filaments generally thread-like; staminodes 0 or 5–many, outer often petal-like; ovary generally cylindric, placentas generally 3, style thread-like, stigma 3-furrowed or -lobed
Fruit generally tapered to base, sometimes curved
Seeds generally many, grain- to prism-like (triangular in X -section), angled, or lenticular and winged (important to identification)
Species in genus: ± 50 species: w US, ± tropical Am
Reference: [Darlington 1934 Ann Missouri Bot Garden 21:103–226]


M. micrantha (Hook. & Arn.) Torr. & A. Gray

Annual 10–80 cm
Stem erect, green
Leaf 1–18 cm, irregularly dentate or wavy
Inflorescence: bract widely ovate, entire to crenate, often concealing flower
Flower: sepals 1.5–2 mm; petals 2.5–4.5 mm; stamens ± 20, 1.5–4 mm; outer 5 filaments widened, tip 2-forked; style 2–3(5) mm
Fruit 6–13 mm, 1.5–2.5 mm wide, cylindric, generally straight (curved < 20°)
Seeds 5–10, pyramid-shaped, smooth; angles grooved; end walls often oblique
Chromosomes: n=9
Ecology: Open, often disturbed places, chaparral, oak woodland
Elevation: < 1600 m.
Bioregional distribution: Outer North Coast Ranges, San Francisco Bay Area, Outer South Coast Ranges, s Channel Islands, Western Transverse Ranges, San Gabriel Mountains, Peninsular Ranges
Distribution outside California: Baja California

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