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Agoseris retrorsa

Higher Taxonomy
Family: AsteraceaeView DescriptionDichotomous Key

Common Name: SUNFLOWER FAMILY
Habit: 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.
Genera In Family: +- 1500 genera, 23000 species: worldwide, many habitats. Note: 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; Bahia in Hymenothrix; 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 Picradeniopsis; Trimorpha in Erigeron; Venidium in Arctotis; Whitneya in Arnica. Amauriopsis in TJM2 (2012) treated here in Hymenothrix; Arida in Leucosyris; Bahia in Picradeniopsis.
Unabridged Note: Largest family of vascular plants in California and of eudicots globally.
eFlora Treatment Author: David J. Keil, except as noted
Scientific Editor: David J. Keil, Bruce G. Baldwin.
Genus: AgoserisView DescriptionDichotomous Key

Habit: Perennial herb 15--65(+) cm, generally erect. Leaf: petiole generally not purple; blade 15--45 cm, +- oblanceolate, acute (to obtuse), entire to lobed; lobes generally 2--4 pairs, +- lanceolate, +- spreading or angled toward leaf tip; +- glabrous, glaucous or not, hairs, if present, white-opaque, glandless. Inflorescence: peduncle becoming +- glabrous, base generally remaining hairy, base of head +- becoming glabrous (hairy), +- glandless; involucre 15--20 mm in flower, 20--40 mm in fruit; phyllaries generally rosy-purple except margin, +- darker spotted or tipped; outer lance-ovate to obovate, tapered to acute, +- (sparsely) hairy to tomentose, hairs generally +- yellow-translucent, glandular (occasionally mixed with white-opaque, glandless hairs), margin +- ciliate; inner elongating with fruit. Flower: generally 50--150; tube 8--10 mm, ligule generally 6--8 mm, +- equaling (exceeding) involucre, orange or yellow, generally drying +- purple; anthers 2--4 mm. Fruit: outermost generally different; body 8--10 mm, +- fusiform, tip generally gradually tapered; ribs straight, uniform, generally minutely coarse-hairy; beak 5--10 mm, generally = body; pappus 10--14 mm, in 2--3 series.
Note: Uncommon and confusing sp. of hybrid origin, the California populations involving Agoseris aurantiaca × Agoseris grandiflora and/or Agoseris monticola.

Agoseris retrorsa (Benth.) Greene
NATIVE
Habit: Perennial herb 10--65(+) cm, +- erect. Leaf: petiole +- purple; blade generally 10--30 cm, linear to lance-elliptic, long-tapered, generally pinnately lobed (toothed or entire); lobes generally 7--9 pairs, generally lance-linear, generally angled toward leaf base (spreading); +- hairy, hairs white-opaque, glandless. Inflorescence: peduncles becoming +- glabrous; base of head hairy; involucre 20--30 mm in flower, 40--60 mm in fruit; phyllaries generally rosy-purple (especially toward base) except margin (rarely all green), not spotted; outer phyllaries lanceolate to deltate (or oblong), obtuse to long-tapered, +- glabrous or hairs white-opaque, glandless, margin ciliate to tomentose; inner phyllaries generally early-elongating. Flower: 10--100; tube 10--20 mm, ligule 6--15 mm, exceeding (equaling) involucre, yellow; anthers 2--5 mm. Fruit: +- all alike; body 5--7 mm, +- obconic, tip +- truncate; ribs straight, +- uniform, glabrous or minutely puberulent; beak 15--25 mm, slender, (< 3)3--4 × body; pappus generally 15--20 mm, in 4--6 series. Chromosomes: 2n=18.
Ecology: Scrub, oak woodland, conifer forest; Elevation: generally 900--1800 m. Bioregional Distribution: CA-FP (exc coast, GV, ChI); Distribution Outside California: to Washington, Utah, Arizona, Baja California. Flowering Time: Apr--Aug
eFlora Treatment Author: David J. Keil
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Citation for this treatment: David J. Keil Agoseris retrorsa, in Jepson Flora Project (eds.) Jepson eFlora, http://ucjeps.berkeley.edu/eflora/eflora_display.php?tid=797, accessed on November 17, 2017.

Citation for the whole project: Jepson Flora Project (eds.) 2017, Jepson eFlora, http://ucjeps.berkeley.edu/eflora/, accessed on November 17, 2017.


Agoseris retrorsa
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© 2003 Steve Matson
Agoseris retrorsa
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© 2011 Neal Kramer
Agoseris retrorsa
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© 2003 Steve Matson
Agoseris retrorsa
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© 2009 Keir Morse
Agoseris retrorsa
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© 2009 Thomas Stoughton
Agoseris retrorsa
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© 2009 Vernon Smith

More photos of Agoseris retrorsa in CalPhotos


Geographic subdivisions for Agoseris retrorsa:
CA-FP (exc coast, GV, ChI);
Markers link to CCH specimen records. Yellow markers indicate records that may provide evidence for eFlora range revision or may have georeferencing or identification issues. Purple markers indicate specimens collected from a garden, greenhouse, or other non-wild location.
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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).

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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.