Asterales

Last updated

Asterales
A sunflower.jpg
Sunflower, Helianthus annuus
Scientific classification OOjs UI icon edit-ltr.svg
Kingdom: Plantae
Clade: Tracheophytes
Clade: Angiosperms
Clade: Eudicots
Clade: Asterids
Clade: Campanulids
Order: Asterales
Link [1]
Families

Asterales ( /ˌæstəˈreɪliːz/ ASS-ter-RAY-leez) [2] is an order of dicotyledonous flowering plants that includes the large family Asteraceae (or Compositae) known for composite flowers made of florets, and ten families related to the Asteraceae. [3] While asterids in general are characterized by fused petals, composite flowers consisting of many florets create the false appearance of separate petals (as found in the rosids).

Contents

The order is cosmopolitan (plants found throughout most of the world including desert and frigid zones), and includes mostly herbaceous species, although a small number of trees (such as the Lobelia deckenii , the giant lobelia, and Dendrosenecio , giant groundsels) and shrubs are also present.

Asterales are organisms that seem to have evolved from one common ancestor. Asterales share characteristics on morphological and biochemical levels. Synapomorphies (a character that is shared by two or more groups through evolutionary development) include the presence in the plants of oligosaccharide inulin, a nutrient storage molecule used instead of starch; and unique stamen morphology. The stamens are usually found around the style, either aggregated densely or fused into a tube, probably an adaptation in association with the plunger (brush; or secondary) pollination that is common among the families of the order, wherein pollen is collected and stored on the length of the pistil.

Taxonomy

The name and order Asterales is botanically venerable, dating back to at least 1926 in the Hutchinson system of plant taxonomy when it contained only five families, of which only two are retained in the APG III classification. Under the Cronquist system of taxonomic classification of flowering plants, Asteraceae was the only family in the group, but newer systems (such as APG II and APG III) have expanded it to 11. In the classification system of Rolf Dahlgren the Asterales were in the superorder Asteriflorae (also called Asteranae).

The order Asterales currently includes 11 families, the largest of which are the Asteraceae, with about 25,000 species, and the Campanulaceae (bellflowers), with about 2,000 species. The remaining families count together for less than 1500 species. The two large families are cosmopolitan, with many of their species found in the Northern Hemisphere, and the smaller families are usually confined to Australia and the adjacent areas, or sometimes South America.

Only the Asteraceae have composite flower heads; the other families do not, but share other characteristics such as storage of inulin that define the 11 families as more closely related to each other than to other plant families or orders such as the rosids.

The phylogenetic tree according to APG III for the Campanulid clade is as below. [4]

Campanulid clade   (similar to Euasterids II in APG II)

Phylogeny

Although most extant species of Asteraceae are herbaceous, the examination of the basal members in the family suggests that the common ancestor of the family was an arborescent plant, a tree or shrub, perhaps adapted to dry conditions, radiating from South America. Less can be said about the Asterales themselves with certainty, although since several families in Asterales contain trees, the ancestral member is most likely to have been a tree or shrub.

Because all clades are represented in the Southern Hemisphere but many not in the Northern Hemisphere, it is natural to conjecture that there is a common southern origin to them. Asterales belong to angiosperms or flowering plants, a clade that appeared about 140 million years ago.[ citation needed ] The Asterales order probably originated in the Cretaceous (145 – 66 Mya) on the supercontinent Gondwana which broke up from 184 – 80 Mya, forming the area that is now Australia, South America, Africa, India and Antarctica.

Asterales contain about 14% of eudicot diversity. From an analysis of relationships and diversities within the Asterales and with their superorders, estimates of the age of the beginning of the Asterales have been made, which range from 116 Mya to 82Mya. [4] However few fossils have been found, of the Menyanthaceae-Asteraceae clade in the Oligocene, about 29 Mya.

Fossil evidence of the Asterales is rare and belongs to rather recent epochs, so the precise estimation of the order's age is quite difficult. An Oligocene (34 – 23 Mya) pollen is known for Asteraceae and Goodeniaceae, and seeds from Oligocene and Miocene (23 – 5.3 Mya) are known for Menyanthaceae and Campanulaceae respectively. [5] According to molecular clock calculations, the lineage that led to Asterales split from other plants about 112 million years ago [6] or 94 million years ago. [7]

Biogeography

The core Asterales are Stylidiaceae (six genera), APA clade (Alseuosmiaceae, Phellinaceae and Argophyllaceae, together seven genera), MGCA clade (Menyanthaceae, Goodeniaceae, Calyceraceae, in total twenty genera), and Asteraceae (about sixteen hundred genera). Other Asterales are Rousseaceae (four genera), Campanulaceae (eighty-four genera) and Pentaphragmataceae (one genus).

All Asterales families are represented in the Southern Hemisphere; however, Asteraceae and Campanulaceae are cosmopolitan and Menyanthaceae nearly so. [8]

Uses

The Asterales, by dint of being a super-set of the family Asteraceae, include some species grown for food, including the sunflower ( Helianthus annuus ), lettuce (Lactuca sativa) and chicory ( Cichorium ). [9] Many are also used as spices and traditional medicines.

Asterales are common plants and have many known uses. For example, pyrethrum (derived from Old World members of the genus Chrysanthemum ) is a natural insecticide with minimal environmental impact. [10] Wormwood, derived from a genus that includes the sagebrush, is used as a source of flavoring for absinthe, a bitter classical liquor of European origin. [11]

Related Research Articles

<span class="mw-page-title-main">Asteraceae</span> Large family of flowering plants

Asteraceae is a large family of flowering plants that consists of over 32,000 known species in over 1,900 genera within the order Asterales. The number of species in Asteraceae is rivaled only by the Orchidaceae, and which is the larger family is unclear as the quantity of extant species in each family is unknown. The Asteraceae were first described in the year 1740 and given the original name Compositae. The family is commonly known as the aster, daisy, composite, or sunflower family.

<span class="mw-page-title-main">Malpighiales</span> Eudicot order of flowering plants

The Malpighiales comprise one of the largest orders of flowering plants, containing about 36 families and more than 16,000 species, about 7.8% of the eudicots. The order is very diverse, containing plants as different as the willow, violet, poinsettia, manchineel, rafflesia and coca plant, and are hard to recognize except with molecular phylogenetic evidence. It is not part of any of the classification systems based only on plant morphology. Molecular clock calculations estimate the origin of stem group Malpighiales at around 100 million years ago (Mya) and the origin of crown group Malpighiales at about 90 Mya.

<span class="mw-page-title-main">Rosales</span> Order of flowering plants

Rosales is an order of flowering plants. It is sister to a clade consisting of Fagales and Cucurbitales. It contains about 7,700 species, distributed into about 260 genera. Rosales comprise nine families, the type family being the rose family, Rosaceae. The largest of these families are Rosaceae (91/4828) and Urticaceae (53/2625). The order Rosales is divided into three clades that have never been assigned a taxonomic rank. The basal clade consists of the family Rosaceae; another clade consists of four families, including Rhamnaceae; and the third clade consists of the four urticalean families.

<span class="mw-page-title-main">Solanales</span> Order of dicot flowering plants

The Solanales are an order of flowering plants, included in the asterid group of dicotyledons. Some older sources used the name Polemoniales for this order.

<span class="mw-page-title-main">Gentianales</span> Order of flowering plant

Gentianales is an order of flowering plant, included within the asterid clade of eudicots. It comprises more than 20,000 species in about 1,200 genera in 5 families. More than 80% of the species in this order belong to the family Rubiaceae.

<span class="mw-page-title-main">Campanulaceae</span> Family of flowering plants comprising bellflowers

The family Campanulaceae, of the order Asterales, contains nearly 2400 species in 84 genera of herbaceous plants, shrubs, and rarely small trees, often with milky sap. Among them are several familiar garden plants belonging to the genera Campanula (bellflower), Lobelia, and Platycodon (balloonflower). Campanula rapunculus and Codonopsis lanceolata are eaten as vegetables. Lobelia inflata, L. siphilitica and L. tupa and others have been used as medicinal plants. Campanula rapunculoides may be a troublesome weed, particularly in gardens, while Legousia spp. may occur in arable fields.

<span class="mw-page-title-main">Menyanthaceae</span> Family of flowering plants

Menyanthaceae is a family of aquatic and wetland plants in the order Asterales. There are approximately 60-70 species in six genera distributed worldwide. The simple or compound leaves arise alternately from a creeping rhizome. In the submersed aquatic genus Nymphoides, leaves are floating and support a lax, umbellate or racemose inflorescence. In other genera the inflorescence is erect and consists of one to many flowers. The sympetalous, insect-pollinated flowers are five-parted and either yellow or white. The petals are ciliate or adorned with lateral wings. Fruit type is a capsule.

<span class="mw-page-title-main">Burseraceae</span> Family of flowering plants

The Burseraceae are a moderate-sized family of 17-19 genera and about 540 species of woody flowering plants. The actual numbers given in taxonomic sources differ according to taxonomic revision at the time of writing. The Burseraceae are also known as the torchwood family, the frankincense and myrrh family, or simply the incense tree family. The family includes both trees and shrubs; its species are native to tropical regions of Africa, Asia, Australasia, and the Americas.

<span class="mw-page-title-main">Eudicots</span> Clade of flowering plants

The eudicots, Eudicotidae, or eudicotyledons are a clade of flowering plants (angiosperms) which are mainly characterized by having two seed leaves (cotyledons) upon germination. The term derives from dicotyledon. Historically, authors have used the terms tricolpates or non-magnoliid dicots. The current botanical terms were introduced in 1991, by evolutionary botanist James A. Doyle and paleobotanist Carol L. Hotton, to emphasize the later evolutionary divergence of tricolpate dicots from earlier, less specialized, dicots.

<span class="mw-page-title-main">Rosids</span> Large clade of flowering plants

The rosids are members of a large clade of flowering plants, containing about 70,000 species, more than a quarter of all angiosperms.

<span class="mw-page-title-main">Asterids</span> Clade of eudicot angiosperms

In the APG IV system (2016) for the classification of flowering plants, the name asterids denotes a clade. Asterids is the largest group of flowering plants, with more than 80,000 species, about a third of the total flowering plant species. Well-known plants in this clade include the common daisy, forget-me-nots, nightshades, the common sunflower, petunias, yacon, morning glory, lettuce, sweet potato, coffee, lavender, lilac, olive, jasmine, honeysuckle, ash tree, teak, snapdragon, sesame, psyllium, garden sage, blueberries, table herbs such as mint, basil, and rosemary, and rainforest trees such as Brazil nut.

The APG system of plant classification is the first version of a modern, mostly molecular-based, system of plant taxonomy. Published in 1998 by the Angiosperm Phylogeny Group, it was replaced by the improved APG II in 2003, APG III system in 2009 and APG IV system in 2016.

The APG II system of plant classification is the second, now obsolete, version of a modern, mostly molecular-based, system of plant taxonomy that was published in April 2003 by the Angiosperm Phylogeny Group. It was a revision of the first APG system, published in 1998, and was superseded in 2009 by a further revision, the APG III system.

<span class="mw-page-title-main">Goodeniaceae</span> Family of flowering plants

Goodeniaceae is a family of flowering plants in the order Asterales. It contains about 404 species in twelve genera. The family is distributed mostly in Australia, except for the genus Scaevola, which is pantropical. Its species are found across most of Australia, being especially common in arid and semi-arid climates.

<span class="mw-page-title-main">Paracryphiaceae</span> Family of shrubs

The Paracryphiaceae are a family of woody shrubs and trees native to Australia, southeast Asia, and New Caledonia. In the APG III system of 2009, the family is placed in its own order, Paracryphiales, in the campanulid clade of the asterids. In the earlier APG II system, the family was unplaced as to order and included only Paracryphia.

The APG III system of flowering plant classification is the third version of a modern, mostly molecular-based, system of plant taxonomy being developed by the Angiosperm Phylogeny Group (APG). Published in 2009, it was superseded in 2016 by a further revision, the APG IV system.

<span class="mw-page-title-main">Superrosids</span> Clade of flowering plants

The superrosids are members of a large clade of flowering plants, containing more than 88,000 species, and thus more than a quarter of all angiosperms.

<span class="mw-page-title-main">Pentapetalae</span> Group of eudicots known as core eudicots

In phylogenetic nomenclature, the Pentapetalae are a large group of eudicots that were informally referred to as the "core eudicots" in some papers on angiosperm phylogenetics. They comprise an extremely large and diverse group accounting for about 65% of the species richness of the angiosperms, with wide variability in habit, morphology, chemistry, geographic distribution, and other attributes. Classical systematics, based solely on morphological information, was not able to recognize this group. In fact, the circumscription of the Pentapetalae as a clade is based on strong evidence obtained from DNA molecular analysis data.

<span class="mw-page-title-main">Superasterids</span> Clade of flowering plants

The superasterids are members of a large clade of flowering plants, containing more than 122,000 species.

References

  1. ↑ Angiosperm Phylogeny Group (2009). "An update of the Angiosperm Phylogeny Group classification for the orders and families of flowering plants: APG III". Botanical Journal of the Linnean Society. 161 (2): 105–121. doi: 10.1111/j.1095-8339.2009.00996.x . hdl: 10654/18083 .
  2. ↑ Stearn, William Thomas (2004). Botanical Latin. Timber Press. ISBN   978-0-88192-627-9 . Retrieved 14 April 2020.
  3. ↑ Kubitzki, K. (1990). The Families and Genera of Vascular Plants: Flowering Plants, Eudicots: Asterales. Springer. Retrieved 14 April 2020.
  4. 1 2 "Angiosperm Phylogeny Website". Mobot.org. Retrieved 12 June 2012.
  5. ↑ Bremer, K.; Gustafsson, M. H. G. (1997). "East Gondwana ancestry of the sunflower alliance of families". Proceedings of the National Academy of Sciences of the United States of America. 94 (17): 9188–9190. Bibcode:1997PNAS...94.9188B. doi: 10.1073/pnas.94.17.9188 . PMC   23106 . PMID   9256457.
  6. ↑ Bremer, K.; Friis, E. M.; Bremer, B. (2004). "Molecular phylogenetic dating of asterid flowering plants shows early Cretaceous diversification". Systematic Biology. 53 (3): 496–505. doi: 10.1080/10635150490445913 . ISSN   1063-5157. PMID   15503676.
  7. ↑ Susana Magallón & Amanda Castillo (2009), "Angiosperm diversification through time", American Journal of Botany, 96 (1): 349–365, doi:10.3732/ajb.0800060, PMID   21628193
  8. ↑ Lundberg, Johannes (2009). Funk, Vicki A. (ed.). Systematics, Evolution, and Biogeography of Compositae (PDF). International Association for Plant Taxonomy. pp. 157–169. ISBN   978-3-9501754-3-1. Archived (PDF) from the original on 9 October 2022. Retrieved 14 April 2020.
  9. ↑ "A Brief Overview of the Compositae, Lettuce and Sunflower". 28 October 2015. Retrieved 14 April 2020.
  10. ↑ Wolff, Anita, ed. (2008). Britannica Concise Encyclopedia. Encyclopaedia Britannica, Inc. p. 403. ISBN   978-1-59339-492-9 . Retrieved 14 April 2020.
  11. ↑ Wondrich, David (5 August 2008). "The Five Best Bottles of Absinthe". Esquire .

Further reading

This page is based on this Wikipedia article
Text is available under the CC BY-SA 4.0 license; additional terms may apply.
Images, videos and audio are available under their respective licenses.