Asteraceae - Revision history

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{{Taxobox
| color = lightgreen
| name = Sunflowers
| image = Aster-alpinus.JPG
| image_width = 250px
| image_caption = ''[[Aster alpinus]]''
| regnum = [[Plant]]ae
| divisio = [[Flowering plant|Magnoliophyta]]
| classis = [[Magnoliopsida]]
| ordo = [[Asterales]]
| familia = '''Asteraceae'''
| familia_authority = [[Martynov]], 1820
| synonyms = ''Compositae'' [[Giseke]]
| type_genus = ''[[Aster (flower)|Aster]]''
| type_genus_authority= [[Carolus Linnaeus|L.]]
| diversity = About 1500 genera and 23,000 species
| diversity_link = List of Asteraceae genera
| subdivision_ranks = Subfamilies
| subdivision =
[[Barnadesioideae]] 
[[Cichorioideae]] 
:Tribe [[Arctotidae]] 
:Tribe [[Cardueae]] 
:Tribe [[Eremothamneae]] 
:Tribe [[Lactuceae]] 
:Tribe [[Liabeae]] 
:Tribe [[Mutisieae]] 
:Tribe [[Tarchonantheae]] 
:Tribe [[Vernonieae]] 
[[Asteroideae]] 
:Tribe [[Anthemideae]] 
:Tribe [[Astereae]] 
:Tribe [[Calenduleae]] 
:Tribe [[Eupatorieae]] 
:Tribe [[Gnaphalieae]] 
:Tribe [[Helenieae]] 
:Tribe [[Heliantheae]] 
:Tribe [[Inuleae]] 
:Tribe [[Plucheae]] 
:Tribe [[Senecioneae]] 
:Tribe [[Tageteae]] 
'''See also [[List of Asteraceae genera]]'''
}}

The family '''Asteraceae''' or, alternatively, '''Compositae''', known as the '''aster''', '''daisy''' or '''sunflower family''', is a taxon of [[dicot]]yledonous [[flowering plant]]s. The family name is derived from the genus ''[[Aster (flower)|Aster]]'' and refers to the [[star]]-shaped flower head of its members, epitomized well by the [[Bellis perennis|daisy]]. The Asteraceae is the second largest family in the Division [[Flowering plant|Magnoliophyta]], with some 1,100 genera (see the [[List_of_Asteraceae_genera]]) and over 20,000 recognized species. Only the orchid family ([[Orchidaceae]]) is larger, with about 25,000 described species <ref>[http://www.flmnh.ufl.edu/orchidatol/ Introduction to assembling the Tree of Life: Orchidaceae]</ref>.

== Description ==
Plants belonging to the Asteraceae share ''all'' the following characteristics (Judd et al., 1999). None of these traits, taken separately, can be considered [[Synapomorphy|synapomorphic]].
* The [[inflorescence]] is an involucrate [[capitulum]] ([[head (botany)|flower head]])
* Tubular/disc florets are actinomorphic, ligulate/ray florets are zygomorphic
* [[Anther]]s are syngenesious, i.e. with the [[stamens]] fused together at their edges, forming a tube
* The [[ovary (plants)|ovary]] has basal arrangement of the [[ovule]]s
* One [[ovule]] per ovary
* The calyx ([[sepal]]s) of the florets are modified to form a [[pappus]], a tuft of hairs, which often appears on the mature [[fruit]]
* The [[fruit]] is an [[achene]]
* In the essential oils [[Sesquiterpene]]s are present, but iridoids are lacking.

[[Image:Bidens_flwr.jpg|thumb|left|A typical Asteraceae flower head (here ''[[Bidens torta]]'') showing the individual flowers]]
[[Image:Flower head.jpg|thumb|left|Flowers of a [[sunflower]] with different forms and phases (sterile ray flowers, disc flowers in female, male and unopened phases)]]
The most common characteristic of all these plants is an inflorescence or '''flower head'''; a densely packed cluster of many small, individual [[flowers]], usually called '''florets''' (meaning "small flowers").

Plants in the family Asteraceae typically have one or both of two kinds of ''florets''. The outer perimeter of a flower head like that of a [[sunflower]] is composed of florets possessing a long strap-like [[petal]], termed a '''ligule'''; these are the '''ray florets'''. The inner portion of the flower head (or ''disc'') is composed of small flowers with tubular [[petal|corollas]]; these are the '''disc florets'''. The composition of asteraceous inflorescences varies from all ray flowers (like [[dandelion]]s, genus ''Taraxacum'') to all disc flowers (like [[pineapple weed]]s).

The composite nature of the inflorescences of these plants led early taxonomists to call this family the Compositae. Although the rules governing naming conventions for plant families state that the name should come from the [[type (botany)|type genus]], in this case ''Aster'' and thus Asteraceae. However, the long prevailing name Compositae is also authorized as an alternative family name ([[ICBN]] Art. 18.6).

The numerous genera are divided into about 13 tribes. Only one of these, Lactuceae, is considered distinct enough to be a subfamily (subfamily Cichorioideae); the remainder, which are mostly overlapping, are put in the subfamily Asteroideae (Wagner, Herbst, and Sohmer, 1990).

==Uses==
Commercially important plants in the Asteraceae include the food crops [[lettuce]], [[chicory]], [[globe artichoke]], [[sunflower]], [[yacón]], [[safflower]] and [[Jerusalem artichoke]]. [[Guayule]] is a source of [[hypoallergenic]] [[latex]].

Many members of Asteraceae are copious [[nectar (plant)|nectar]] producers and are useful for evaluating [[pollinator]] populations during their bloom. ''[[Centaurea]]'' (knapweed), ''[[Helianthus annuus]]'' (domestic sunflower), and some species of ''[[Solidago]]'' (goldenrod) are major "[[honey]] plants" for [[beekeeper]]s. ''Solidago'' produces relatively high protein [[pollen]], which helps [[honey bee]]s overwinter.

Many members of the family are grown as ornamental plants for their flowers, e.g., [[chrysanthemum]]s and some are important ornamental crops for the cut flower industry. Some Asteraceae are economically important in the sense that they are considered noxious weeds, e.g., [[dandelion]]s.

 
[[Image:Ray.floret01.jpg|thumb|left|Ray floret : A = ovary; B = pappus; C = theca; D = ligule; E = style with stigma ]]
[[Image:Disc floret01.jpg||thumb|right|Disc floret : A = ovary; B = tube of corolla with teeth of the corolla; C = theca; D = style with stigma ]]
 

== Footnote ==

[[Image:Gnaphalium supinum0.jpg|thumb|right|200px|''Helichrysum petiolare'']]

<div class="references-small" style="column-count:2;-moz-column-count:2;">
<references/>
</div>

== References ==
* [http://www.itis.usda.gov/servlet/SingleRpt/SingleRpt?search_topic=TSN&search_value=35420 ITIS report 2002-09-10]
* International Code of Botanical Nomenclature (ICBN, St. Louis Code). 1999. [http://www.bgbm.fu-berlin.de/iapt/nomenclature/code/SaintLouis/0000St.Luistitle.htm website] (Published as ''Regnum Vegetabile 138''. Koeltz Scientific Books, Königstein. ISBN 3-904144-22-7)
* Walters, Dirk R. and David J. Keil (1996). ''Vascular plant taxonomy''. 4th ed. Kendall/Hunt Publishing Company. Dubuque, Iowa.
* Wagner,W.L., D.R. Herbst, and S.H. Sohmer. 1990. ''Manual of the Flowering Plants of Hawai‘i'', Vol. I. University of Hawaii Press, Honolulu. 988 pp.
* Judd, W.S., C.S. Campbell, E.A. Kellogg, and P.F. Stevens. 1999. Plant Systematics: A Phylogenetic Approach. Sinauer Associates, Sunderland, MA.
* D. J. N. Hind, C. Jeffrey & G. V. Pope (eds.), Advances in Compositae systematics. - Royal Bot. Gardens, Kew, 469 pp., 1995

==External links==
* {{dmoz|/Science/Biology/Flora_and_Fauna/Plantae/Magnoliophyta/Magnoliopsida/Asteraceae/}}

{{commonscat|Asteraceae}}



[[Category:Plant families]]
[[Category:Asteraceae| ]]

@@ Line 12: / Line 12: @@
 | familia = Asteraceae
 }}
-The family '''Asteraceae''' or, alternatively, '''Compositae''', known as the '''aster''', '''daisy''' or '''sunflower family''', is a taxon of [[dicot]]yledonous [[flowering plant]]s.  The family name is derived from the genus ''[[Aster (flower)|Aster]]'' and refers to the [[star]]-shaped flower head of its members, epitomized well by the [[Bellis perennis|daisy]].  The Asteraceae is the second largest family in the Division [[Flowering plant|Magnoliophyta]], with some  1,100 genera (see the [[List_of_Asteraceae_genera]]) and over 20,000 recognized species. Only the orchid family ([[Orchidaceae]]) is larger, with about 25,000 described species <ref>[http://www.flmnh.ufl.edu/orchidatol/ Introduction to assembling the  Tree of Life: Orchidaceae]</ref>.
+The family '''Asteraceae''' (syn. Compositae), known as the '''aster''', '''daisy''' or '''sunflower family''', is a taxon of [[dicot]]yledonous [[flowering plant]]s.  The family name is derived from the genus ''[[Aster (genus)|Aster]]'' and refers to the [[star]]-shaped flower head of its members, exemplified by the [[Bellis perennis|daisy]].  The Asteraceae is the second largest family in the Division [[Flowering plant|Magnoliophyta]], with about 1,100 genera and over 20,000 species. Only the orchid family ([[Orchidaceae]]) is larger, with about 25,000 described species <ref>[http://www.flmnh.ufl.edu/orchidatol/ Introduction to assembling the  Tree of Life: Orchidaceae]</ref>.
 {{Inc|
 Compositae (name having reference to the aggregation of the flowers into heads or false flowers, i.e., composite flowers). Composite Family. Herbs, shrubs, or rarely trees, sometimes twining, often with milky juice: leaves alternate, opposite or whorled, very diverse in shape, size and texture : flowers bisexual or unisexual, regular or irregular, epigynous; subtended by a bract called chaff; aggregated into 1- to many- flowered involucrate heads; calyx (pappus) reduced to hairs, scales, awns, or a border, or wanting; corolla gamopetalous, normally regular, 4—5-lobed; the lobes valvate; in one tribe bilabiate; often enlarged and split down one side, and flattened out (ligulate or ray flowers); stamens usually 4-5, epipetalous, syngenesious, alternating with the corolla lobes; carpels 2; ovary 1-celled, 1-ovuled, inferior; style 1; stigmas 2, rarely 1: fruit an achene, often crowned by the persistent pappus; seed exalbuminous.
-This is the largest family of flowering plants, consisting of more than 800 genera and 10,000 to 12,000 species, distributed over all parts of the earth, each tribe usually having a definite center of distribution. The largest genera are: Senecio, 1,200 species; Centaurea, 470; Vernonia, 450; Hieracium, 400; Helichrysum, 300; Baccharis, 275; Cousinia, 210; Artemisia, 200; Crepis, 170; Erigeron, 150; Chrysanthemum, 140; Saussurea, 125; Gnaphalium, 120; Circium, 120; Scorzonera, 100; Anthemis, 100. The Compositae, taken in the broad sense, is a well-defined family not closely related to any other large families. Its affinities are with the Campanulaceae, Dipsacaceae, and Valerianaceae. In general, the involucrate heads, epigynous gamopetalous flowers, syngenesious stamens, 1-seeded dry fruits and exalbuminous seeds are distinctive. In some genera the heads have no ray flowers (discoid), in others they have a marginal row, and in still others all the flowers are ligulate. Except in the last case, the ray flowers are without stamens, and frequently without a pistil (neutral). The style-branches are very diverse, and are important in the characterization of tribes. They are often provided with sweeping hairs which push the pollen from the introrse anthers up out of the anther tube as the style elongates. The anthers are caudate in two tribes, and in some genera the filaments contract abruptly when stimulated by touch. In Ambrosia and Xanthium, the anthers are separate, and the bracts of the 1-2-flowered pistillate involucre are fused, woody, indehiscent, and covered with spines or hooks.
+This is one of the largest families of flowering plants, distributed over all parts of the earth, each tribe usually having a definite center of distribution. The largest genera are: Senecio, 1,200 species; Centaurea, 470; Vernonia, 450; Hieracium, 400; Helichrysum, 300; Baccharis, 275; Cousinia, 210; Artemisia, 200; Crepis, 170; Erigeron, 150; Chrysanthemum, 140; Saussurea, 125; Gnaphalium, 120; Circium, 120; Scorzonera, 100; Anthemis, 100. The Compositae, taken in the broad sense, is a well-defined family not closely related to any other large families. Its affinities are with the Campanulaceae, Dipsacaceae, and Valerianaceae. In general, the involucrate heads, epigynous gamopetalous flowers, syngenesious stamens, 1-seeded dry fruits and exalbuminous seeds are distinctive. In some genera the heads have no ray flowers (discoid), in others they have a marginal row, and in still others all the flowers are ligulate. Except in the last case, the ray flowers are without stamens, and frequently without a pistil (neutral). The style-branches are very diverse, and are important in the characterization of tribes. They are often provided with sweeping hairs which push the pollen from the introrse anthers up out of the anther tube as the style elongates. The anthers are caudate in two tribes, and in some genera the filaments contract abruptly when stimulated by touch. In Ambrosia and Xanthium, the anthers are separate, and the bracts of the 1-2-flowered pistillate involucre are fused, woody, indehiscent, and covered with spines or hooks.
 The family is divided by Hoffman into 13 tribes, several of which are by some authors considered separate families.
@@ Line 35: / Line 35: @@
 Many Compositae are ornamental. The species of Helichrysum, Anaphalis, and related genera, have papery involucres, and furnish well-known everlastings.
-More than one hundred and fifty genera are in cultivation in N. America, or are important weeds. Many of our most important and most showy ornamental plants belong to the Compositae. Among these genera are: Achillea (Milfoil, Yarrow, Sneezewort); Ageratum; Anaphalis (Everlasting, Moonshine): Antennaria (Everlasting, Cat's-ear, Pussy's Toes, Ladies' Tobacco); Anthemis (Chamomile, Mayweed, Golden Marguerite); Arctium (Burdock); Arnica (Mountain Tobacco, Mountain Snuff); Artemisia (Wormwood, Tarragon, Estragon, Southernwood, Roman Wormwood, Old Man and Old Woman, Sage Brush); Aster (Aster, Starwort, Michaelmas Daisy); Bidens (Bur Marigold, Beggar's Ticks, Pitchfork Bur); Boltonia (False Chamomile); Brachycome (Swan River Daisy); Brickellia (Tassel Flower); Buphthalmum; Calendula (Marigold); Callistephus (China Aster); Cnicus or Carbenia (Blessed Thistle); Carthamus (Safflower, False Saffron); Centaurea (Centaury, Dusty Miller, Bachelor's Button, Cornflower, Knapweed, Bluebottle, Bluet, Ragged Sailor, Sweet Sultan, Basket Flower, Hardheads); Chaenactis; Chrysanthemum (Feverfew, Golden Feather, Turfing Daisy, Marguerite, Paris Daisy, Costmary, Mint Geranium, Giant Daisy, Ox-eye Daisy, White- weed); Cichorium (Chicory, Succory); Cineraria; Circium or Cnicus (Common Thistles); Coreopsis (Tick- seed, Golden Wave); Cosmos; Cynara (Artichoke, Cardoon) ; Dahlia; Doronicum (Leopard's-Bane); Echinacea or Brauneria (Purple Coneflower); Echinops (Globe Thistle); Emilia (Tassel Flower); Erigeron (Flea- bane, Poor Robin's Plantain); Eupatorium (Boneset, Joe-Pye Weed, Thoroughwort, White Snakeroot); Felicia (Blue Daisy, Blue Marguerite): Gaillardia; Gazania (Peacock Gazania); Grindelia (Gum Plant); Gynura (Velvet Plant); Helenium (Sneezeweed); Helianthus (Sunflower, Indian Potato, Jerusalem Artichoke); Helichrysum; Heliopsis; Helipterum; Hidalgoa (Treasure Vine); Hieracium (Hawkweed, Rattlesnake Weed, Devil's Paint-brush); Inula (Elecampane); Krigia (Dwarf Dandelion); Lactuca (Lettuce); Leontopodium (Edelweiss); Leptosyne; Liatris (Blazing Star, Button Snakeroot); Lonas (African Daisy); Madia (Tarweed); Matricaria; Mikania (Climbing Hempweed, Climbing Boneset); Onopordon (Scotch Thistle); Parthenium (American Feverfew, Prairie Dock); Pentachaeta; Petasites (Winter Heliotrope, Sweet Coltsfoot); Piqueria; Podolepis; Polymnia (Leaf-cup); Prenanthes (Rattle snake Root); Rudbeckia (Black-eyed Susan, Yellow Daisy, Coneflower, Golden Glow); Santolina (Lavender Cotton); Scolymus (Golden Thistle, Spanish Oyster
+More than 150 genera are in cultivation, or are important weeds. Many of our most important and most showy ornamental plants belong to the Compositae. Among these genera are: Achillea (Milfoil, Yarrow, Sneezewort); Ageratum; Anaphalis (Everlasting, Moonshine): Antennaria (Everlasting, Cat's-ear, Pussy's Toes, Ladies' Tobacco); Anthemis (Chamomile, Mayweed, Golden Marguerite); Arctium (Burdock); Arnica (Mountain Tobacco, Mountain Snuff); Artemisia (Wormwood, Tarragon, Estragon, Southernwood, Roman Wormwood, Old Man and Old Woman, Sage Brush); Aster (Aster, Starwort, Michaelmas Daisy); Bidens (Bur Marigold, Beggar's Ticks, Pitchfork Bur); Boltonia (False Chamomile); Brachycome (Swan River Daisy); Brickellia (Tassel Flower); Buphthalmum; Calendula (Marigold); Callistephus (China Aster); Cnicus or Carbenia (Blessed Thistle); Carthamus (Safflower, False Saffron); Centaurea (Centaury, Dusty Miller, Bachelor's Button, Cornflower, Knapweed, Bluebottle, Bluet, Ragged Sailor, Sweet Sultan, Basket Flower, Hardheads); Chaenactis; Chrysanthemum (Feverfew, Golden Feather, Turfing Daisy, Marguerite, Paris Daisy, Costmary, Mint Geranium, Giant Daisy, Ox-eye Daisy, White-weed); Cichorium (Chicory); Cineraria; Cirsium (common thistles); Coreopsis (Tick-seed, Golden Wave); Cosmos; Cynara (Artichoke, Cardoon); Dahlia; Doronicum (Leopard's-Bane); Echinacea or Brauneria (Purple Coneflower); Echinops (Globe Thistle); Emilia (Tassel Flower); Erigeron (Flea- bane, Poor Robin's Plantain); Eupatorium (Boneset, Joe-Pye Weed, Thoroughwort, White Snakeroot); Felicia (Blue Daisy, Blue Marguerite): Gaillardia; Gazania (Peacock Gazania); Grindelia (Gum Plant); Gynura (Velvet Plant); Helenium (Sneezeweed); Helianthus (Sunflower, Indian Potato, Jerusalem Artichoke); Helichrysum; Heliopsis; Helipterum; Hidalgoa (Treasure Vine); Hieracium (Hawkweed, Rattlesnake Weed, Devil's Paint-brush); Inula (Elecampane); Krigia (Dwarf Dandelion); Lactuca (Lettuce); Leontopodium (Edelweiss); Leptosyne; Liatris (Blazing Star, Button Snakeroot); Lonas (African Daisy); Madia (Tarweed); Matricaria; Mikania (Climbing Hempweed, Climbing Boneset); Onopordon (Cotton Thistle); Parthenium (American Feverfew, Prairie Dock); Pentachaeta; Petasites (Winter Heliotrope, Sweet Coltsfoot); Piqueria; Podolepis; Polymnia (Leaf-cup); Prenanthes (Rattle snake Root); Rudbeckia (Black-eyed Susan, Yellow Daisy, Coneflower, Golden Glow); Santolina (Lavender Cotton); Scolymus (Golden Thistle); Scorzonera (Black Salsify); Senecio (Groundsel, Canada Plant, Ragwort, German Ivy, Leopard Plant, Dusty Miller); Silphium (Rosin-Weed, Compass Plant, Prairie Dock, Cup Plant); Solidago (Goldenrod); Spilanthes(Para Cress); Stokesia (Stoke's Aster); Tagetes (French Marigold, African Marigold); Tanacetum (Tansy); Taraxacum (Dandelion) ; Thelysperma; Townsendia; Tragopogon (Salsify, Goat's Beard); Trilisa; Tussilago (Coltsfoot); Verbesina (Crownbeard); Vernonia (Ironweed); Zinnia (Zinnia).
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