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Key to families | Table of families and genera

Specimen numbers are hyperlinked to records in the Consortium of California Herbaria data view where possible. Taxa are hyperlinked to entries in the Jepson Interchange via the "[Online Interchange]" link.



Raymund Chan & Robert Ornduff

Annual, perennial herb, glabrous or hairy. Stem: generally branched, generally erect, < 60 cm. Leaf: opposite (or distal-most alternate), < 20 cm, entire to pinnately cut. Inflorescence: heads radiate (disciform), 1 or in cyme-like cluster; involucre cylindric to obconic, bell-shaped, or hemispheric; phyllaries 4–18 in 1(2) series, free or ± fused; receptacle narrowly conic to hemispheric, smooth, pitted, or rough, epaleate. Ray flower: 4–16; ray generally yellow (short or 0). Disk flower: generally many; corolla generally (4)5-lobed, generally yellow to ± orange; anther tip awl-shaped to triangular; style tips triangular or dome-shaped, generally hair-tufted. Fruit: < 5 mm, cylindric to obovoid, black to gray; pappus of awns, scales, or 0.
18 species: western North America, Chile. (Greek: female student of Plato who dressed as a man) [Chan & Ornduff 2006 FNANM 21:336–347] Generally self-sterile.
Unabridged references: [Chan et al. 2001 Int J Plant Sci 162:1347–1360]

Key to Lasthenia

1. Phyllaries ± fused

2. Phyllaries fused < 1/2; leaves entire to pinnately lobed ..... L. conjugens

2' Phyllaries fused > 2/3; leaves entire

3. Pappus present ..... L. glaberrima

3' Pappus 0

4. Fruit strongly flattened, margin fringed with blunt hairs ..... L. chrysantha

4' Fruit not strongly flattened, glabrous or face papillate or hairy

5. Fruit hairs short, curved ..... L. ferrisiae

5' Fruit glabrous or papillate ..... L. glabrata

6. Fruit papillate ..... subsp. coulteri

6' Fruit glabrous ..... subsp. glabrata

1' Phyllaries free

7. Receptacle narrowly conic; phyllaries generally 4–6

8. Ray <= 1 mm; involucre cylindric to narrowly obconic; disk corolla generally 4-lobed ..... L. microglossa

8' Ray > 2 mm; involucre obconic or bell-shaped; disk corolla generally 5-lobed

9. Stem coarse, hairy; anther tip triangular ..... L. debilis

9' Stem fine, wiry, glabrous proximally; anther tip awl-shaped ..... L. leptalea

7' Receptacle conic or hemispheric; phyllaries generally > 6

10. All leaves ± entire or with 3–5+ teeth; corolla dark red in alkali solution

11. Perennial herb (annual); coastal

12. Stem erect, 0–few-branched; root fleshy; leaf generally < 2 mm wide ..... L. californica subsp. bakeri

12' Stem ± decumbent, generally branched; root fibrous; leaf generally > 2 mm wide ..... L. californica subsp. macrantha

11' Annual; coastal or inland

13. Pappus of 1–7 clear, brown, linear to awl-like scales or 0 ..... L. californica subsp. californica

13' Pappus of (2)4(6) opaque, white, lance-ovate scales or 0 ..... L. gracilis

10' Mid-cauline leaves generally pinnately lobed; corolla yellow in alkali solution

14. Involucre obconic; phyllaries persistent; pappus of lanceolate to ovate scales tapered to tip ..... L. platycarpha

14' Involucre hemispheric to obconic; phyllaries persistent or deciduous with fruit; pappus of 1 or 2 kinds per fruit, or 0

15. Plant glandular, scented; pappus elements of 1 kind (if of 2 kinds, awns 0) or 0 ..... L. coronaria

15' Plant glandless, unscented; pappus elements of 2 kinds or 0

16. Fruit >= 2 mm

17. Ray corolla <= 3 mm; pappus awns >= 4, rarely 0 ..... L. maritima

17' Ray corolla > 4 mm; pappus awns 2–3(4) or 0 ..... L. minor

16' Fruit < 1.5 mm

18. Pappus generally of 1 long awn and few to many short scales ..... L. burkei

18' Pappus generally of 3 or more long awns mixed with several short scales, or rarely 0 ..... L. fremontii


Citation for the whole project: Jepson Flora Project (eds.) [year] Jepson eFlora, [accessed on month, day, year]
Citation for an individual treatment: [Author of taxon treatment] [year]. [Taxon name] in Jepson Flora Project (eds.) Jepson eFlora, [URL for treatment]. Accessed on [month, day, year].
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