The eudicots, Eudicotidae, or eudicotyledons are a
clade of
flowering plants mainly characterized by having two
seed leaves
A cotyledon (; ; ; , gen. (), ) is a significant part of the embryo within the seed of a plant, and is defined as "the embryonic leaf in seed-bearing plants, one or more of which are the first to appear from a germinating seed." The nu ...
upon germination. The term derives from
Dicotyledon
The dicotyledons, also known as dicots (or, more rarely, dicotyls), are one of the two groups into which all the flowering plants (angiosperms) were formerly divided. The name refers to one of the typical characteristics of the group: namely, t ...
s.
Traditionally they were called tricolpates or non-
magnoliid
Magnoliids (or Magnoliidae or Magnolianae) are a clade of flowering plants. With more than 10,000 species, including magnolias, nutmeg, bay laurel, cinnamon, avocado, black pepper, tulip tree and many others, it is the third-largest group of a ...
dicots by previous authors. The 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.
Numerous familiar plants are eudicots, including many common food plants, trees, and ornamentals. Some common and familiar eudicots include
sunflower
The common sunflower (''Helianthus annuus'') is a large annual forb of the genus ''Helianthus'' grown as a crop for its edible oily seeds. Apart from cooking oil production, it is also used as livestock forage (as a meal or a silage plant), as ...
,
dandelion
''Taraxacum'' () is a large genus of flowering plants in the family Asteraceae, which consists of species commonly known as dandelions. The scientific and hobby study of the genus is known as taraxacology. The genus is native to Eurasia and Nor ...
,
forget-me-not
''Myosotis'' ( ) is a genus of flowering plants in the family Boraginaceae. The name comes from the Ancient Greek "mouse's ear", which the foliage is thought to resemble. In the northern hemisphere they are colloquially known as forget-me-nots ...
,
cabbage
Cabbage, comprising several cultivars of ''Brassica oleracea'', is a leafy green, red (purple), or white (pale green) biennial plant grown as an annual vegetable crop for its dense-leaved heads. It is descended from the wild cabbage ( ''B.&nbs ...
,
apple,
buttercup
''Ranunculus'' is a large genus of about almost 1700 to more than 1800 species of flowering plants in the family Ranunculaceae. Members of the genus are known as buttercups, spearworts and water crowfoots.
The genus is distributed in Europe, ...
,
maple
''Acer'' () is a genus of trees and shrubs commonly known as maples. The genus is placed in the family Sapindaceae.Stevens, P. F. (2001 onwards). Angiosperm Phylogeny Website. Version 9, June 2008 nd more or less continuously updated since http ...
, and
macadamia
''Macadamia'' is a genus of four species of trees in the flowering plant family Proteaceae. They are indigenous to Australia, native to northeastern New South Wales and central and southeastern Queensland specifically. Two species of the genus ...
. Most leafy trees of midlatitudes also belong to eudicots, with notable exceptions being magnolias and tulip trees which belong to
magnoliids
Magnoliids (or Magnoliidae or Magnolianae) are a clade of flowering plants. With more than 10,000 species, including magnolias, nutmeg, bay laurel, cinnamon, avocado, black pepper, tulip tree and many others, it is the third-largest group of a ...
, and ''
Ginkgo biloba'', which is not an
angiosperm
Flowering plants are plants that bear flowers and fruits, and form the clade Angiospermae (), commonly called angiosperms. The term "angiosperm" is derived from the Greek words ('container, vessel') and ('seed'), and refers to those plants th ...
.
Description
The close relationships among flowering plants with
tricolpate pollen grains was initially seen in morphological studies of
shared derived characters. These plants have a distinct trait in their pollen grains of exhibiting three colpi or grooves paralleling the polar axis.
Later
molecular evidence confirmed the genetic basis for the evolutionary relationships among flowering plants with tricolpate pollen grains and dicotyledonous traits. The term means "true dicotyledons", as it contains the majority of plants that have been considered dicots and have
characteristics of the dicots. One of the genetic traits which defines the eudicots is the
duplication of
DELLA proteināencoding genes in their
most recent common ancestor. The term "eudicots" has subsequently been widely adopted in
botany
Botany, also called , plant biology or phytology, is the science of plant life and a branch of biology. A botanist, plant scientist or phytologist is a scientist who specialises in this field. The term "botany" comes from the Ancient Greek w ...
to refer to one of the two largest clades of
angiosperm
Flowering plants are plants that bear flowers and fruits, and form the clade Angiospermae (), commonly called angiosperms. The term "angiosperm" is derived from the Greek words ('container, vessel') and ('seed'), and refers to those plants th ...
s (constituting over 70% of the angiosperm species),
monocots
Monocotyledons (), commonly referred to as monocots, ( Lilianae ''sensu'' Chase & Reveal) are grass and grass-like flowering plants (angiosperms), the seeds of which typically contain only one embryonic leaf, or cotyledon. They constitute one of ...
being the other. The remaining angiosperms include
magnoliids
Magnoliids (or Magnoliidae or Magnolianae) are a clade of flowering plants. With more than 10,000 species, including magnolias, nutmeg, bay laurel, cinnamon, avocado, black pepper, tulip tree and many others, it is the third-largest group of a ...
and what are sometimes referred to as
basal angiosperms
The basal angiosperms are the flowering plants which diverged from the lineage leading to most flowering plants. In particular, the most basal angiosperms were called the ANITA grade, which is made up of ''Amborella'' (a single species of shrub f ...
or paleodicots, but these terms have not been widely or consistently adopted, as they do not refer to a
monophyletic group.
Taxonomy
The earlier name for the eudicots is tricolpates, a name which refers to the grooved structure of the
pollen. Members of the group have tricolpate pollen, or forms derived from it. These pollens have three or more pores set in furrows called colpi. In contrast, most of the other
seed plants
A spermatophyte (; ), also known as phanerogam (taxon Phanerogamae) or phaenogam (taxon Phaenogamae), is any plant that produces seeds, hence the alternative name seed plant. Spermatophytes are a subset of the embryophytes or land plants. They inc ...
(that is the
gymnosperms, the monocots and the paleodicots) produce monosulcate pollen, with a single pore set in a differently oriented groove called the sulcus. The name "tricolpates" is preferred by some botanists to avoid confusion with the dicots, a nonmonophyletic group.
The name "eudicots" (plural) is used in the
APG systems (from
APG system
The APG system (Angiosperm Phylogeny Group 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 ...
, of 1998, to
APG IV system
The APG IV system of flowering plant classification is the fourth version of a modern, mostly molecular-based, system of plant taxonomy for flowering plants (angiosperms) being developed by the Angiosperm Phylogeny Group (APG). It was published ...
, of 2016) for classification of angiosperms. It is applied to a
clade, a monophyletic group, which includes most of the (former) dicots.
"Tricolpate" is a synonym for the "
Eudicot
The eudicots, Eudicotidae, or eudicotyledons are a clade of flowering plants mainly characterized by having two seed leaves upon germination. The term derives from Dicotyledons.
Traditionally they were called tricolpates or non-magnoliid dicots ...
"
monophyletic group, the "true
dicotyledons
The dicotyledons, also known as dicots (or, more rarely, dicotyls), are one of the two groups into which all the flowering plants (angiosperms) were formerly divided. The name refers to one of the typical characteristics of the group: namely, ...
" (which are distinguished from all other flowering plants by their tricolpate
pollen structure). The number of
pollen grain
Pollen is a powdery substance produced by seed plants. It consists of pollen grains (highly reduced microgametophytes), which produce male gametes (sperm cells). Pollen grains have a hard coat made of sporopollenin that protects the gametoph ...
''furrows'' or ''pores'' helps classify the
flowering plants, with eudicots having three
colpi (tricolpate), and other groups having one
sulcus.
[
Pollen ]aperture
In optics, an aperture is a hole or an opening through which light travels. More specifically, the aperture and focal length of an optical system determine the cone angle of a bundle of rays that come to a focus in the image plane.
An opti ...
s are any modification of the wall of the pollen grain. These modifications include thinning, ridges and pores, they serve as an exit for the pollen contents and allow shrinking and swelling of the grain caused by changes in moisture content. The elongated apertures/ furrows in the pollen grain are called ''colpi'' (singular ''colpus''), which, along with pores, are a chief criterion for identifying the pollen classes.
Subdivisions
The eudicots can be divided into two groups: the basal eudicots and the core eudicots. Basal eudicot is an informal name for a paraphyletic group. The core eudicots are a monophyletic group.[
] A 2010 study suggested the core eudicots can be divided into two clades, Gunnerales
The Gunnerales are an order of flowering plants. In the APG III system (2009) and APG IV system (2016) it contains two genera: ''Gunnera'' (in family Gunneraceae) and '' Myrothamnus'' (in family Myrothamnaceae). In the Cronquist system (1981), ...
and a clade called Pentapetalae, comprising all the remaining core eudicots.[
The Pentapetalae can be then divided into three clades:
* ]Dilleniales
The Dilleniales are an order of flowering plants, potentially containing one family, Dilleniaceae. The APG III system of 2009, like the earlier APG II system of 2003, left the Dilleniaceae unplaced as to order, while noting that the name Dillen ...
* superrosids consisting of Saxifragales
The Saxifragales (saxifrages) are an order of flowering plants (Angiosperms). They are an extremely diverse group of plants which include trees, shrubs, perennial herbs, succulent and aquatic plants. The degree of diversity in terms of vege ...
and rosids (the APG IV system
The APG IV system of flowering plant classification is the fourth version of a modern, mostly molecular-based, system of plant taxonomy for flowering plants (angiosperms) being developed by the Angiosperm Phylogeny Group (APG). It was published ...
includes the Vitales in the rosids)
* superasterids consisting of Santalales
The Santalales are an order of flowering plants with a cosmopolitan distribution, but heavily concentrated in tropical and subtropical regions. It derives its name from its type genus '' Santalum'' (sandalwood). Mistletoe is the common name for ...
, Berberidopsidales
Berberidopsidales is an order of Southern Hemisphere woody flowering plants. The name is newly accepted in the APG III system of plant taxonomy. APG II system, of 2003, mentions the possibility of recognizing the order, as comprising the familie ...
, Caryophyllales
Caryophyllales ( ) is a diverse and heterogeneous order of flowering plants that includes the cacti, carnations, amaranths, ice plants, beets, and many carnivorous plants. Many members are succulent, having fleshy stems or leaves. The betala ...
and asterids
In the APG IV system (2016) for the classification of flowering plants, the name asterids denotes a clade (a monophyletic group). Asterids is the largest group of flowering plants, with more than 80,000 species, about a third of the total fl ...
This division of the eudicots is shown in the following cladogram:[Based on:]
----
The following is a more detailed breakdown according to APG IV
The APG IV system of flowering plant classification is the fourth version of a modern, mostly molecular-based, system of plant taxonomy for flowering plants (angiosperms) being developed by the Angiosperm Phylogeny Group (APG). It was publish ...
, showing within each clade and orders:
* clade Eudicots
*: order Ranunculales
*: order Proteales
*: order Trochodendrales
*: order Buxales
*: clade Core eudicots
*:: order Gunnerales
The Gunnerales are an order of flowering plants. In the APG III system (2009) and APG IV system (2016) it contains two genera: ''Gunnera'' (in family Gunneraceae) and '' Myrothamnus'' (in family Myrothamnaceae). In the Cronquist system (1981), ...
*:: order Dilleniales
The Dilleniales are an order of flowering plants, potentially containing one family, Dilleniaceae. The APG III system of 2009, like the earlier APG II system of 2003, left the Dilleniaceae unplaced as to order, while noting that the name Dillen ...
*:: clade Superrosids
The superrosids are members of a large clade (monophyletic group) of flowering plants, containing more than 88,000 species, and thus more than a quarter of all angiosperms.
The clade is divided into 18 orders as defined in APG IV system. These ...
*::: order Saxifragales
The Saxifragales (saxifrages) are an order of flowering plants (Angiosperms). They are an extremely diverse group of plants which include trees, shrubs, perennial herbs, succulent and aquatic plants. The degree of diversity in terms of vege ...
*::: clade Rosids
*:::: order Vitales
The Vitaceae are a family of flowering plants, with 14 genera and around 910 known species, including common plants such as grapevines (''Vitis'' spp.) and Virginia creeper (''Parthenocissus quinquefolia''). The family name is derived from the g ...
*:::: clade Fabids
The rosids are members of a large clade (monophyletic group) of flowering plants, containing about 70,000 species, more than a quarter of all angiosperms.
The clade is divided into 16 to 20 orders, depending upon circumscription and classificati ...
*::::: order Fabales
The Fabales are an order of flowering plants included in the rosid group of the eudicots in the Angiosperm Phylogeny Group II classification system. In the APG II circumscription, this order includes the families Fabaceae or legumes (including ...
*::::: order Rosales
*::::: order Fagales
*::::: order Cucurbitales
The Cucurbitales are an order of flowering plants, included in the rosid group of dicotyledons. This order mostly belongs to tropical areas, with limited presence in subtropical and temperate regions. The order includes shrubs and trees, together ...
*::::: order Oxalidales
Oxalidales is an order of flowering plants, included within the rosid subgroup of eudicots. Compound leaves are common in Oxalidales and the majority of the species in this order have five or six sepals and petals. The following families are ty ...
*::::: order Malpighiales
The Malpighiales comprise one of the largest orders of flowering plants, containing about 36 families and more than species, about 7.8% of the eudicots. The order is very diverse, containing plants as different as the willow, violet, poinset ...
*::::: order Celastrales
The Celastrales are an order of flowering plants found throughout the tropics and subtropics, with only a few species extending far into the temperate regions. The 1200"Lepidobotryaceae", "Parnassiaceae", and "Celastraceae" In: Klaus Kubitzki (ed ...
*::::: order Zygophyllales
The Zygophyllales are an order of dicotyledonous plants, comprising the following two families:
* Family Zygophyllaceae
* Family Krameriaceae
According to the Angiosperm Phylogeny Group (APG II) both families are unplaced to order, but never ...
*:::: clade Malvids
*::::: order Geraniales
Geraniales is a small order of flowering plants, included within the rosid subclade of eudicots. The largest family in the order is Geraniaceae with over 800 species. In addition, the order includes the smaller Francoaceae with about 40 speci ...
*::::: order Myrtales
The Myrtales are an order of flowering plants placed as a sister to the eurosids II clade as of the publishing of the ''Eucalyptus grandis'' genome in June 2014.
The APG III system of classification for angiosperms still places it within the eu ...
*::::: order Crossosomatales
The Crossosomatales are an order, first recognized as such by APG II. They are flowering plants included within the Rosid eudicots.
Description
Species assigned to the Crossosomatales have in common flowers that are positioned solitarily, wit ...
*::::: order Picramniales
Picramniaceae is a small, mainly neotropical family of four genera '' Aenigmanu'', '' Alvaradoa'', '' Nothotalisia'' and '' Picramnia''. The family is the only member of the order Picramniales. Members of the family were formerly placed in the f ...
*::::: order Malvales
*::::: order Brassicales
The Brassicales (or Cruciales) are an order of flowering plants, belonging to the eurosids II group of dicotyledons under the APG II system. One character common to many members of the order is the production of glucosinolate (mustard oil) compo ...
*::::: order Huerteales
Huerteales is the botanical name for an order of flowering plants.Peter F. Stevens (2001 onwards). "Huerteales". In: Angiosperm Phylogeny Website. In: Missouri Botanical Garden Website. (see ''External links'' below) It is one of the 17 orders t ...
*::::: order Sapindales
*:: clade Superasterids
The superasterids are members of a large clade ( monophyletic group) of flowering plants, containing more than 122,000 species.
The clade is divided into 20 orders as defined in APG IV system. These orders, in turn, together comprise about 14 ...
*::: order Berberidopsidales
Berberidopsidales is an order of Southern Hemisphere woody flowering plants. The name is newly accepted in the APG III system of plant taxonomy. APG II system, of 2003, mentions the possibility of recognizing the order, as comprising the familie ...
*::: order Santalales
The Santalales are an order of flowering plants with a cosmopolitan distribution, but heavily concentrated in tropical and subtropical regions. It derives its name from its type genus '' Santalum'' (sandalwood). Mistletoe is the common name for ...
*::: order Caryophyllales
Caryophyllales ( ) is a diverse and heterogeneous order of flowering plants that includes the cacti, carnations, amaranths, ice plants, beets, and many carnivorous plants. Many members are succulent, having fleshy stems or leaves. The betala ...
*::: clade Asterids
In the APG IV system (2016) for the classification of flowering plants, the name asterids denotes a clade (a monophyletic group). Asterids is the largest group of flowering plants, with more than 80,000 species, about a third of the total fl ...
*:::: order Cornales
The Cornales are an order of flowering plants, early diverging among the asterids, containing about 600 species. Plants within the Cornales usually have four-parted flowers, drupaceous fruits, and inferior to half-inferior gynoecia topped with d ...
*:::: order Ericales
*:::: clade Campanulids
In the APG IV system (2016) for the classification of flowering plants, the name asterids denotes a clade (a monophyletic group). Asterids is the largest group of flowering plants, with more than 80,000 species, about a third of the total floweri ...
*::::: order Aquifoliales
The Aquifoliales are an order of flowering plants, including the Aquifoliaceae (holly) family, and also the Helwingiaceae (2-5 species of temperate Asian shrubs) and the Phyllonomaceae (4 species of Central American trees and shrubs). In 2 ...
*::::: order Asterales
Asterales () 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. While asterids in general are char ...
*::::: order Escalloniales
Escalloniaceae is a family of flowering plants consisting of about 130 species in seven genera. In the APG II system it is one of eight families in the euasterids II clade (campanulids) that are unplaced as to order. More recent research has prov ...
*::::: order Bruniales
Bruniales is a valid botanic name at the rank of order. Until recently it was not in use, but a 2008 study suggested that Bruniaceae and Columelliaceae are sister clades. The latest revision of the APG system, APG III, places both families as t ...
*::::: order Apiales
The Apiales are an order of flowering plants. The families are those recognized in the APG III system. This is typical of the newer classifications, though there is some slight variation and in particular, the Torriceliaceae may also be divi ...
*::::: order Dipsacales
The Dipsacales are an order of flowering plants, included within the asterid group of dicotyledons. In the APG III system of 2009, the order includes only two families, Adoxaceae and a broadly defined Caprifoliaceae. Some well-known members of ...
*::::: order Paracryphiales
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 ...
*:::: clade Lamiids
In the APG IV system (2016) for the classification of flowering plants, the name asterids denotes a clade (a monophyletic group). Asterids is the largest group of flowering plants, with more than 80,000 species, about a third of the total floweri ...
*::::: order Solanales
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.
Taxonomy
Under the older Cronquist system, the latter three families were placed elsew ...
*::::: order Lamiales
*::::: order Vahliales
:''The later homonym Vahlia Dahl is now known as Dombeya.''
''Vahlia'' is a genus of herbs and subshrubs that grow in Africa and the Indian subcontinent. There are at least five species.
The genus is placed alone in family ''Vahliaceae''. This ...
*::::: order Gentianales
Gentianales is an order of flowering plants, 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.
M ...
*::::: order Boraginales
Boraginales is an order of flowering plants in the asterid clade. It includes the Boraginaceae and a number of other families, with a total of about 125 genera and 2,700 species. Its herbs, shrubs, trees and lianas (vines) have a worldwide dis ...
*::::: order Garryales
*::::: order Metteniusales
Metteniusaceae are a family of flowering plants, the only family in the order Metteniusales. It consists of about 10 genera and 50 species of trees, shrubs, and lianas, primarily of the tropics. The family was formerly restricted to just ''Metten ...
*::::: order Icacinales
Icacinales is an order of Angiosperms.
The order did not exist in the 2009 APG III system, and was added in the 2016 APG IV system, including two families, Icacinaceae and Oncothecaceae
''Oncotheca'' is a genus of tree endemic to New Caledon ...
References
Bibliography
*
*
Eudicots
in Stevens, P. F. (2001 onwards)
Angiosperm Phylogeny Website
Version 7, May 2006.
External links
*
*
Eudicots
', Tree of Life Web Project
Dicots
Plant Life Forms
{{Taxonbar, from=Q165468
Plant unranked clades
Early Cretaceous plants
Extant Early Cretaceous first appearances