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Key to families | Table of families and genera

Previous taxon Indexes to all accepted names and synonyms:
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David J. Keil, except as noted

Annual to tree. Leaf: basal and/or cauline, alternate, opposite, rarely whorled, simple to 2+ × compound. Inflorescence: 1° inflorescence a head, resembling a flower, of several types (see below), 1–many in generally ± cyme-like cluster; each head generally with ± calyx-like involucre of 1–many series of phyllaries (involucre bracts); receptacle of head flat to conic or columnar, paleate (bearing paleae = receptacle bracts) or epaleate; flowers 1–many per head. Flower: bisexual, unisexual, or sterile, ± small, of several types (see below); calyx 0 or modified into ± persistent pappus of bristles, scales, and/or awns; corolla radial or bilateral (0), lobes generally (0)3–5; stamens 4–5, filaments generally free, generally fused to corolla at tube/throat junction, anthers generally fused into cylinder around style, anther base generally rounded or cordate (deeply sagittate or with tail-like appendages), tip (= flattened appendage) generally projecting beyond pollen sac; pistil 1, 2-carpeled, ovary inferior, 1-chambered, 1-seeded, placenta basal, style 1, tip generally ± 2-branched (except in some staminate disk flowers), branch tips truncate or generally bearing ± brush-like appendages; stigmas 2, generally on adaxial faces of style branches. Fruit: achene (also called a cypsela) (drupe in Chrysanthemoides), cylindric to ovoid, sometimes compressed, generally deciduous with pappus attached.
± 1500 genera, 23000 species: worldwide, many habitats. Flower and head types differ in form and sexual condition. A disk flower has a generally radial corolla, with a cylindric tube, expanded throat, and generally 5 lobes. Disk flowers are generally bisexual and fertile but occasionally staminate with reduced ovaries. Discoid heads comprise only disk flowers. A radiant head is a variant of a discoid head, with peripheral disk flower corollas expanded, often bilateral. A ray flower corolla is bilateral, generally with a slender tube and flattened petal-like ray (single lip composed of generally 3 lobes). Ray flowers are generally pistillate or sterile (occasionally lacking styles). Radiate heads have peripheral ray flowers and central disk flowers. Disciform heads superficially resemble discoid heads, with pistillate or sterile flowers that lack rays, together with or separate from disk flowers. A ligulate flower is bisexual, with a bilateral, generally ephemeral corolla and 5-lobed ligule. Liguliflorous heads comprise only ligulate flowers. See glossary p. 31 for illustrations of family characteristics. Echinops sphaerocephalus L., Gaillardia aristata Pursh, Gaillardia pulchella Foug., Hymenothrix loomisii S.F. Blake, Tagetes erecta L., Thelesperma megapotamicum (Spreng.) Kuntze are waifs. Melampodium perfoliatum Kunth, historic urban waif. Ageratum conyzoides L., Guizotia abyssinica (L. f.) Cass., Santolina chamaecyparisus L., orth. var. are rare or uncommon escapes from cultivation. Dyssodia papposa, Ismelia carinata (Schousb.) Sch. Bip. [Chrysanthemum carinatum Schousb.], Mantisalca salmantica (L.) Briq. & Cavill. are historical or extirpated waifs in California. Inula helenium L. not documented in California. Taxa of Aster in TJM (1993) treated here in Almutaster, Eucephalus, Eurybia, Ionactis, Oreostemma, Sericocarpus, Symphyotrichum; Chamomilla in Matricaria; Cnicus in Centaurea; Conyza in Erigeron and Laennecia; Dugaldia in Hymenoxys; Erechtites in Senecio; Hymenoclea in Ambrosia; Lembertia in Monolopia; Osteospermum ecklonis in Dimorphotheca; Picris echioides in Helminthotheca; Prionopsis in Grindelia; Raillardiopsis in Anisocarpus and Carlquistia; Schkuhria multiflora in Bahia; Trimorpha in Erigeron; Venidium in Arctotis; Whitneya in Arnica. Taxa of Arida in TJM2 (2012) treated here in Leucosyris. —Scientific Editors: David J. Keil, Bruce G. Baldwin.
Unabridged note: Largest family of vascular plants in California and of eudicots globally.

Key to Asteraceae


Bruce G. Baldwin, adapted from Strother (2006)

Annual [perennial herb], generally taprooted. Stem: generally erect, simple or branched. Leaf: mostly cauline at flower, alternate, sessile (in California), generally 1-veined, linear or elliptic to (ob)ovate or spoon-shaped, entire, toothed, or 1–2-pinnately lobed, minutely coarse-hairy to long-soft-hairy, generally glandular. Inflorescence: heads obscurely radiate or disciform, in ± flat-topped or raceme- or panicle-like clusters; involucres ± obconic, 2–7+ mm diam; phyllaries 20–40+ in 2–4 series, appressed, generally reflexed in fruit, linear to lanceolate, ± (un)equal, margins ± membranous, abaxial face ± green, minutely hairy, generally glandular, midvein not orange to brown; receptacle ± flat, pitted or smooth, epaleate. Pistillate flower: [20]60–100[200]; corolla thread-like, ± yellow, generally distally truncate or 2–5-toothed, ray 0 [0.5–1+ mm]. Disk flower: [2]5–20[30+]; corolla ± yellow, narrowly funnel-shaped, throat > tube, abruptly expanded distally, lobes deltate; anther tip awl-like; style-branch tips ± deltate, papillate. Fruit: oblong to elliptic or obovate, compressed, each edge 1-veined, faces glabrous or ± minutely strigose, often stalked- or sessile-glandular; pappus in California of 9–30+ white to tawny, minutely-barbed, distally long-tapered bristles, in 1 series, ± equal, persistent.
± 18 species: New World. (R.-T.-H. Laennec, French physician, 1781–1826) [Strother 2006 FNANM 20:35–38]
Unabridged disk flower: anther bases minutely cordate.
Unabridged references: [Nesom 1990 Phytologia 68:205–228; Noyes & Rieseberg 1999 Amer J Bot 86:398–412]

L. coulteri (A. Gray) G.L. Nesom COULTER'S HORSEWEED
Annual 1–15 dm. Stem: 1–several from base, generally simple proximally, much-branched distally. Leaf: proximal 2–7(10) cm, 1–2.5 cm wide, widely spoon-shaped to oblong, obscurely lobed or coarsely toothed; distal 1–3 cm, 3–10 mm wide, coarsely toothed or entire. Inflorescence: heads in raceme- or panicle-like clusters; involucre 2.5–3+ mm; receptacle 2–3 mm diam. Pistillate flower: 60–100+; corolla 1.5–2 mm, ± 1/2 style, ray 0. Disk flower: 5–20; corolla 3–4 mm. Fruit: 0.5–1 mm, pale tan; pappus (2.5)3.5–4 mm, ± white.
2n=18. Disturbed sites, clayey or sandy soils, often seasonally wet, alkaline; < 1300 m. s Sierra Nevada Foothills, San Joaquin Valley, Central Western California, Southwestern California, East of Sierra Nevada (except White and Inyo Mountains), Desert; to Colorado, Texas, Mexico. [Conyza coulteri A. Gray] May–Nov [Online Interchange]

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Citation for the whole project: Jepson Flora Project (eds.) 2013. Jepson eFlora,, accessed on Nov 29 2015
Citation for this treatment: [Author of taxon treatment] 2013. Laennecia, in Jepson Flora Project (eds.) Jepson eFlora,, accessed on Nov 29 2015

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click for enlargement Laennecia coulteri
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© 2006 Adonis (Don) Tate

Geographic subdivisions indicated for the distribution of Laennecia coulteri Markers link to CCH specimen records. If the markers are obscured, reload the page [or change window size and reload]. Yellow markers indicate records that may provide evidence for eFlora range revision or may have georeferencing or identification issues.
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).

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Data provided by the participants of the Consortium of California Herbaria.
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CCH collections by month

Duplicates counted once; synonyms included.
Species do not include records of infraspecific taxa.
Blue line denotes eFlora flowering time.