Eudicots#Subdivisions

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.{{Cite journal |last1=Furness |first1=Carol A. |last2=Rudall |first2=Paula J. |date=March 2004 |title=Pollen aperture evolution – a crucial factor for eudicot success? |url=https://linkinghub.elsevier.com/retrieve/pii/S1360138504000196 |journal=Trends in Plant Science |language=en |volume=9 |issue=3 |pages=154–158 |doi=10.1016/j.tplants.2004.01.001 |pmid=15003239|url-access=subscription }}

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 protein-encoding genes in their most recent common ancestor.{{Cite journal |last1=Phokas |first1=A. |last2=Coates |first2=J. C. |year=2021 |title=Evolution of DELLA function and signaling in land plants |journal=Evolution & Development |volume=23 |issue=3 |pages=137–154 |doi=10.1111/ede.12365 |pmc=9285615 |pmid=33428269}} The term "eudicots" has subsequently been widely adopted in botany to refer to one of the two largest clades of angiosperms (constituting over 70% of the angiosperm species), monocots being the other. The remaining angiosperms include magnoliids and what are sometimes referred to as basal angiosperms or paleodicots, but these terms have not been widely or consistently adopted, as they do not refer to a monophyletic group.{{cn|date=June 2024}}

According to molecular clock calculations, the lineage that led to eudicots split from other plants about 134 million years ago{{cite journal |last1= Magallon |first1= S |last2= Gomez-Acevedo |first2= S |last3= Sanchez-Reyes |first3= LL |last4= Tania Hernandez-Hernandez |first4= T |title = A metacalibrated time-tree documents the early rise of flowering plant phylogenetic diversity |journal= New Phytologist |date= 2015 | volume = 207 |issue= 2 |pages= 437–453 | doi = 10.1111/nph.13264|pmid= 25615647 |bibcode= 2015NewPh.207..437M }} or 155–160 million years ago.{{cite journal|last1=Zeng|first1=Liping|last2=Zhang|first2=Qiang|last3=Sun|first3=Renran|last4=Kong|first4=Hongzhi|last5=Zhang|first5=Ning|last6=Ma|first6=Hong|title=Resolution of deep angiosperm phylogeny using conserved nuclear genes and estimates of early divergence times|journal=Nature Communications|date=24 September 2014|volume=5|issue=4956|pages=4956|doi=10.1038/ncomms5956|pmid=25249442|ref={{harvid|Zeng et al|2014}}|pmc=4200517|bibcode=2014NatCo...5.4956Z}} Fossil records suggested that basal eudicots were already diverse around 121 million years ago {{Cite journal |last1=Sun |first1=Ge |last2=Dilcher |first2=David L. |last3=Wang |first3=Hongshan |last4=Chen |first4=Zhiduan |date=2011-03-30 |title=A eudicot from the Early Cretaceous of China |url=https://www.nature.com/articles/nature09811 |journal=Nature |language=en |volume=471 |issue=7340 |pages=625–628 |doi=10.1038/nature09811 |pmid=21455178 |bibcode=2011Natur.471..625S |issn=0028-0836}}.

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 (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.{{harvnb|Judd|Olmstead|2004}}

The name "eudicots" (plural) is used in the APG systems (from APG system, of 1998, to APG IV system, of 2016) for classification of angiosperms. It is applied to a clade, a monophyletic group, which includes most of the (former) dicots.{{cn|date=June 2024}}

"Tricolpate" is a synonym for the "Eudicot" monophyletic group, the "true dicotyledons" (which are distinguished from all other flowering plants by their tricolpate pollen structure). The number of pollen grain furrows or pores helps classify the flowering plants, with eudicots having three colpi (tricolpate), and other groups having one sulcus.{{Cite journal |last=Sporne |first=Kenneth R. |year=1972 |title=Some Observations on the Evolution of Pollen Types in Dicotyledons |journal=New Phytologist |volume=71 |issue=1 |pages=181–5 |doi=10.1111/j.1469-8137.1972.tb04826.x |doi-access=free|bibcode=1972NewPh..71..181S }}

Pollen apertures 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.{{Cite web |last=Davis |first=Owen |date=1999 |title=Pollen Aperture Definitions |url=http://www.geo.arizona.edu/palynology/ppapertr.html |url-status=dead |archive-url=https://web.archive.org/web/20090203035127/http://www.geo.arizona.edu/palynology/ppapertr.html |archive-date=2009-02-03 |access-date=2009-02-16 |website=University of Arizona - Geosciences}}

The eudicots can be divided into two groups: the basal eudicots and the core eudicots.{{Cite journal |last1=Worberg |first1=A |last2=Quandt |first2=D |last3=Barniske |first3=A-M |last4=Löhne |first4=C |last5=Hilu |first5=KW |last6=Borsch |first6=T |year=2007 |title=Phylogeny of basal eudicots: insights from non-coding and rapidly evolving DNA |journal=Organisms Diversity & Evolution |volume=7 |issue=1 |pages=55–77 |doi=10.1016/j.ode.2006.08.001 |doi-access=free|bibcode=2007ODivE...7...55W }} Basal eudicot is an informal name for a paraphyletic group. The core eudicots are a monophyletic group.{{Cite book |last1=Soltis |first1=Douglas E. |author-link1=Douglas E. Soltis |title=Phylogeny and Evolution of Angiosperms |last2=Soltis |first2=Pamela S. |author-link2=Pamela S. Soltis |last3=Endress |first3=Peter K. |last4=Chase |first4=Mark W. |author-link4=Mark Wayne Chase |publisher=Sinauer Associates |year=2005 |isbn=9780878938179 |location=Sunderland, MA}} A 2010 study suggested the core eudicots can be divided into two clades, Gunnerales and a clade called Pentapetalae, comprising all the remaining core eudicots.

The Pentapetalae can be then divided into three clades:{{cn|date=June 2024}}

• Dilleniales
• superrosids consisting of Saxifragales and rosids (the APG IV system includes the Vitales in the rosids)
• superasterids consisting of Santalales, Berberidopsidales, Caryophyllales and asterids

This division of the eudicots is shown in the following cladogram:Based on:
{{Cite web |last=Stevens |first=P.F. |date=2001–2014 |title=Trees |url=http://www.mobot.org/MOBOT/research/APweb/treeapweb2map.html |access-date=2014-11-17 |website=Angiosperm Phylogeny Website}}
{{Cite web |last=Stevens |first=P.F. |date=2001–2016 |title=Eudicots |url=http://www.mobot.org/MOBOT/research/APweb/orders/ranunculalesweb.htm#Eudicots |access-date=2014-11-17 |website=Angiosperm Phylogeny Website}}

{{clade |style=line-height:1em;

|label1=eudicots

|1={{cladex

|label1=basal eudicots

|1=(paraphyletic group: Ranunculales, Proteales, Trochodendrales, Buxales)|state1=double

|label2=core eudicots

|2={{clade

|1=Gunnerales

|label2=Pentapetalae

|2={{clade

|1=Dilleniales

|2={{clade

|label1=superrosids

|1={{clade

|1=Saxifragales

|label2=rosids

|2={{clade

|1=Vitales

|label2=eurosids

|2={{clade

|1=fabids (8 orders)

|2=malvids (8 orders)

}}

}}

}}

|label2=superasterids

|2={{clade

|1=Santalales

|2={{clade

|1=Berberidopsidales

|2={{clade

|1=Caryophyllales

|label2=asterids

|2={{clade

|1=Cornales

|2={{clade

|1=Ericales

|label2=euasterids

|2={{clade

|1=campanulids (7 orders)

|2=lamiids (8 orders)

}}

}}

}}

}}

}}

}}

}}

}}

}}

}}

}}

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The following is a more detailed breakdown according to APG IV, showing within each clade and orders:{{Cite journal |last=Angiosperm Phylogeny Group |year=2016 |title=An update of the Angiosperm Phylogeny Group classification for the orders and families of flowering plants: APG IV |journal=Botanical Journal of the Linnean Society |volume=181 |issue=1 |pages=1–20 |doi=10.1111/boj.12385 |doi-access=free}}

• clade Eudicots
• : order Ranunculales
• : order Proteales
• : order Trochodendrales
• : order Buxales
• : clade Core eudicots
• :: order Gunnerales
• :: order Dilleniales
• :: clade Superrosids
• ::: order Saxifragales
• ::: clade Rosids
• :::: order Vitales
• :::: clade Fabids
• ::::: order Fabales
• ::::: order Rosales
• ::::: order Fagales
• ::::: order Cucurbitales
• ::::: order Oxalidales
• ::::: order Malpighiales
• ::::: order Celastrales
• ::::: order Zygophyllales
• :::: clade Malvids
• ::::: order Geraniales
• ::::: order Myrtales
• ::::: order Crossosomatales
• ::::: order Picramniales
• ::::: order Malvales
• ::::: order Brassicales
• ::::: order Huerteales
• ::::: order Sapindales
• :: clade Superasterids
• ::: order Berberidopsidales
• ::: order Santalales
• ::: order Caryophyllales
• ::: clade Asterids
• :::: order Cornales
• :::: order Ericales
• :::: clade Campanulids
• ::::: order Aquifoliales
• ::::: order Asterales
• ::::: order Escalloniales
• ::::: order Bruniales
• ::::: order Apiales
• ::::: order Dipsacales
• ::::: order Paracryphiales
• :::: clade Lamiids
• ::::: order Solanales
• ::::: order Lamiales
• ::::: order Vahliales
• ::::: order Gentianales
• ::::: order Boraginales
• ::::: order Garryales
• ::::: order Metteniusales
• ::::: order Icacinales

{{Reflist|30em|refs=

{{Cite journal |last1=Moore |first1=Michael J. |last2=Soltis |first2=Pamela S. |last3=Bell |first3=Charles D. |last4=Burleigh |first4=J. Gordon |last5=Soltis |first5=Douglas E. |name-list-style=amp |year=2010 |title=Phylogenetic analysis of 83 plastid genes further resolves the early diversification of eudicots |journal=Proceedings of the National Academy of Sciences |volume=107 |issue=10 |pages=4623–8 |bibcode=2010PNAS..107.4623M |doi=10.1073/pnas.0907801107 |pmc=2842043 |pmid=20176954 |doi-access=free}}

}}

{{Refbegin}}

• {{Cite book |last1=Doyle |first1=J.A. |title=Pollen and Spores. Patterns of Diversification |last2=Hotton |first2=C.L. |publisher=Clarendon Press |year=1991 |isbn=9780198577461 |editor-last=Blackmore |editor-first=S. |series=Systematics Association Publications |volume=44 |pages=169–195 |chapter=Diversification of early angiosperm pollen in a cladistic context |editor-last2=Barnes |editor-first2=S.H.}}
• {{cite journal |first1= Walter S. |last1=Judd |first2=Richard G. |last2=Olmstead |year = 2004 |title = A survey of tricolpate (eudicot) phylogenetic relationships |journal = American Journal of Botany| volume = 91|pages = 1627–44|doi = 10.3732/ajb.91.10.1627|issue = 10|pmid = 21652313 |doi-access = free }}
• [http://www.mobot.org/MOBOT/Research/APweb/orders/ranunculalesweb.htm#Eudicots Eudicots] in Stevens, P. F. (2001 onwards). [http://www.mobot.org/MOBOT/research/APweb Angiosperm Phylogeny Website]. Version 7, May 2006.

{{Refend}}

{{Commons category|Eudicots}}

• {{EOL|283}}
• [http://www.tolweb.org/eudicots Eudicots], Tree of Life Web Project
• {{usurped|1=[https://web.archive.org/web/20150224112718/http://plantlifeforms.com/Classes186/Dicots_Dicotyledoneae_503903_186.aspx Dicots]}} Plant Life Forms

{{Angiosperm orders}}

{{Taxonbar|from=Q165468}}

Category:Plant unranked clades

Category:Early Cretaceous plants

Category:Extant Early Cretaceous first appearances