Editing Beech (section)

== Taxonomy and systematics ==
The most recent classification system of the genus recognizes 14 species in two distinct subgenera, subgenus ''Englerianae'' and ''Fagus''.<ref name="Denk-2024" /> Beech species can be diagnosed by [[Phenotype|phenotypical]] and/or [[Genotype|genotypical]] traits. Species of subgenus ''Engleriana'' are found only in East Asia, and are notably distinct from species of subgenus ''Fagus'' in that these beeches are low-branching trees, often made up of several major trunks with yellowish bark and a substantially different [[Nuclear DNA|nucleome (nuclear DNA)]], especially in noncoding, highly variable gene regions such as the [[Spacer DNA|spacers]] of the nuclear-encoded [[Ribosomal DNA|ribosomal RNA genes (ribosomal DNA)]].<ref name="Cardoni-2021">{{Citation |last1=Cardoni |first1=Simone |title=5S-IGS rDNA in wind-pollinated trees (Fagus L.) encapsulates 55 million years of reticulate evolution and hybrid origins of modern species |date=2021-10-19 |url=https://www.biorxiv.org/content/10.1101/2021.02.26.433057v2 |access-date=2024-10-24 |language=en |doi=10.1111/tpj.15601|biorxiv=10.1101/2021.02.26.433057 |last2=Piredda |first2=Roberta |last3=Denk |first3=Thomas |last4=Grimm |first4=Guido W. |last5=Papageorgiou |first5=Aristotelis C. |last6=Schulze |first6=Ernst-Detlef |last7=Scoppola |first7=Anna |last8=Shanjani |first8=Parvin Salehi |last9=Suyama |first9=Yoshihisa|journal=The Plant Journal |volume=109 |issue=4 |pages=909–926 |pmid=34808015 |pmc=9299691 }}</ref><ref name="Denk-2005">{{Cite journal |last1=Denk |first1=Thomas |last2=Grimm |first2=Guido W. |last3=Hemleben |first3=Vera |date=June 2005 |title=Patterns of molecular and morphological differentiation in Fagus (Fagaceae): phylogenetic implications |url=https://bsapubs.onlinelibrary.wiley.com/doi/10.3732/ajb.92.6.1006 |journal=American Journal of Botany |language=en |volume=92 |issue=6 |pages=1006–1016 |doi=10.3732/ajb.92.6.1006 |pmid=21652485 |issn=0002-9122}}</ref> Further differentiating characteristics include the whitish bloom on the underside of the leaves, the visible tertiary leaf veins, and a long, smooth cupule-peduncle. Originally proposed but not formalized by botanist Chung-Fu Shen in 1992, this group comprised two Japanese species, ''[[Fagus japonica|F.&nbsp;japonica]]'' and ''[[Fagus okamotoi|F.&nbsp;okamotoi]],'' and one Chinese species, ''[[Fagus engleriana|F.&nbsp;engleriana]]''.<ref name="Shen-1992" /> While the status of ''F. okamotoi'' remains uncertain, the most recent systematic treatment based on morphological and genetic data confirmed a third species, ''F. multinervis,'' endemic to [[Ulleungdo]], a South Korean island in the [[Sea of Japan]].<ref name="Denk-2024" /> The beeches of Ulleungdo have been traditionally treated as a subspecies of ''F. engleriana,'' to which they are phenotypically identical,<ref name="Shen-1992" /><ref name="Denk-2003">{{Cite journal |last=Denk |first=T. |date=2003-09-01 |title=Phylogeny of Fagus L. (Fagaceae) based on morphological data |url=https://link.springer.com/article/10.1007/s00606-003-0018-x |journal=Plant Systematics and Evolution |language=en |volume=240 |issue=1 |pages=55–81 |doi=10.1007/s00606-003-0018-x |bibcode=2003PSyEv.240...55D |issn=1615-6110|url-access=subscription }}</ref> or as a variety of ''F. japonica.''<ref>{{Cite journal |last1=Oh |first1=Sang-Hun |last2=Youm |first2=Jung-Won |last3=Kim |first3=Yong-In |last4=Kim |first4=Young-Dong |date=2016-09-01 |title=Phylogeny and Evolution of Endemic Species on Ulleungdo Island, Korea: The Case of Fagus multinervis (Fagaceae) |url=http://openurl.ingenta.com/content/xref?genre=article&issn=0363-6445&volume=41&issue=3&spage=617 |journal=Systematic Botany |language=en |volume=41 |issue=3 |pages=617–625 |doi=10.1600/036364416X692271|url-access=subscription }}</ref> The differ from their siblings by their unique [[Nuclear DNA|nuclear]] and [[Chloroplast DNA|plastid]] genotypes.<ref name="Denk-2024" /><ref name="Jiang-2022">{{Cite journal |last1=Jiang |first1=Lu |last2=Bao |first2=Qin |last3=He |first3=Wei |last4=Fan |first4=Deng-Mei |last5=Cheng |first5=Shan-Mei |last6=López-Pujol |first6=Jordi |last7=Chung |first7=Myong Gi |last8=Sakaguchi |first8=Shota |last9=Sánchez-González |first9=Arturo |last10=Gedik |first10=Aysun |last11=Li |first11=De-Zhu |last12=Kou |first12=Yi-Xuan |last13=Zhang |first13=Zhi-Yong |date=July 2022 |title=Phylogeny and biogeography of Fagus (Fagaceae) based on 28 nuclear single/low-copy loci |url=https://onlinelibrary.wiley.com/doi/10.1111/jse.12695 |journal=Journal of Systematics and Evolution |language=en |volume=60 |issue=4 |pages=759–772 |doi=10.1111/jse.12695 |issn=1674-4918|url-access=subscription }}</ref><ref name="Cardoni-2021" />

The better known subgenus ''Fagus'' beeches are high-branching with tall, stout trunks and smooth silver-gray bark. This group includes five extant species in continental and insular East Asia (''[[Fagus crenata|F. crenata]], [[Fagus longipetiolata|F. longipetiolata]], [[Fagus lucida|F. lucida]]'', and the [[Cryptic speciation|cryptic]] sister species ''[[Fagus hayatae|F. hayatae]]'' and ''[[Fagus pashanica|F. pashanica]]'')'','' two pseudo-cryptic species in [[eastern North America]] ([[Fagus grandifolia|''F.&nbsp;grandifolia'']]'', [[Fagus mexicana|F. mexicana]]''), and a [[species complex]] of at least four species (''[[Fagus caspica|F. caspica]], [[Fagus hohenackeriana|F. hohenackeriana]], [[Fagus orientalis|F. orientalis]], [[Fagus sylvatica|F. sylvatica]]'') in [[Western Eurasia]]. Their genetics are highly complex and include both species-unique [[allele]]s as well as alleles and ribosomal DNA spacers that are shared between two or more species.<ref name="Denk-2024" /> The western Eurasian species are characterized by morphological and genetical gradients.

Research suggests that the first representatives of the modern-day genus were already present in the [[Paleocene]] of [[Arctic]] North America (western [[Greenland]]<ref name="Grímsson-2016">{{Cite journal |last1=Grímsson |first1=Friðgeir |last2=Grimm |first2=Guido W. |last3=Zetter |first3=Reinhard |last4=Denk |first4=Thomas |date=2016-12-01 |title=Cretaceous and Paleogene Fagaceae from North America and Greenland: evidence for a Late Cretaceous split between Fagus and the remaining Fagaceae |url=https://acpa.botany.pl/Cretaceous-and-Paleogene-Fagaceae-nfrom-North-America-and-Greenland-evidence-nfor,118915,0,2.html |journal=Acta Palaeobotanica |volume=56 |issue=2 |pages=247–305 |doi=10.1515/acpa-2016-0016 |issn=2082-0259|doi-access=free }}</ref>) and quickly radiated across the high latitudes of the [[Northern Hemisphere]], with a first [[Biodiversity|diversity]] peak in the [[Miocene]] of northeastern Asia.<ref>{{Cite journal |last1=Denk |first1=Thomas |last2=Grimm |first2=Guido W. |date=2009 |title=The biogeographic history of beech trees |url=https://linkinghub.elsevier.com/retrieve/pii/S0034666709001353 |journal=Review of Palaeobotany and Palynology |language=en |volume=158 |issue=1–2 |pages=83–100 |doi=10.1016/j.revpalbo.2009.08.007|bibcode=2009RPaPa.158...83D |url-access=subscription }}</ref><ref>{{Cite journal |last1=Renner |first1=S. S. |last2=Grimm |first2=Guido W. |last3=Kapli |first3=Paschalia |last4=Denk |first4=Thomas |date=2016-07-19 |title=Species relationships and divergence times in beeches: new insights from the inclusion of 53 young and old fossils in a birth–death clock model |journal=Philosophical Transactions of the Royal Society B: Biological Sciences |language=en |volume=371 |issue=1699 |pages=20150135 |doi=10.1098/rstb.2015.0135 |issn=0962-8436 |pmc=4920336 |pmid=27325832}}</ref> The contemporary species are the product of past, repeated [[Reticulate evolution|reticulate evolutionary processes]] ([[Outcrossing|outbreeding]], [[introgression]], [[Hybrid (biology)|hybridization]]).<ref name="Cardoni-2021" /> As far as studied, heterozygosity and intragenomic variation are common in beech species,<ref name="Cardoni-2021" /><ref name="Denk-2005" /><ref name="Jiang-2022" /> and their chloroplast genomes are nonspecific with the exception of the Western Eurasian and North American species.<ref name="Denk-2024" />

''Fagus'' is the first [[Divergent evolution|diverging]] lineage in the evolution of the [[Fagaceae]] family,<ref name="Grímsson-2016" /><ref>{{Cite journal |last1=Zhou |first1=Biao-Feng |last2=Yuan |first2=Shuai |last3=Crowl |first3=Andrew A. |last4=Liang |first4=Yi-Ye |last5=Shi |first5=Yong |last6=Chen |first6=Xue-Yan |last7=An |first7=Qing-Qing |last8=Kang |first8=Ming |last9=Manos |first9=Paul S. |last10=Wang |first10=Baosheng |date=2022-03-14 |title=Phylogenomic analyses highlight innovation and introgression in the continental radiations of Fagaceae across the Northern Hemisphere |journal=Nature Communications |language=en |volume=13 |issue=1 |pages=1320 |doi=10.1038/s41467-022-28917-1 |issn=2041-1723 |pmc=8921187 |pmid=35288565|bibcode=2022NatCo..13.1320Z }}</ref> which also includes [[oak]]s and [[chestnut]]s.<ref>{{cite journal |last1=Manos |first1=Paul S. |first2=Kelly P. |last2=Steele |title=Phylogenetic analysis of "Higher" Hamamelididae based on Plasid Sequence Data |journal=American Journal of Botany |volume=84 |issue=10 |pages=1407–19 |date=1997 |doi=10.2307/2446139 |jstor=2446139 |pmid=21708548 |url=|doi-access=free }}</ref> The oldest fossils that can be assigned to the beech lineage are 81–82 million years old [[pollen]] from the [[Late Cretaceous]] of [[Wyoming]], United States.<ref name="Grímsson-2016" /> The '''southern beeches''' (genus ''[[Nothofagus]]'') historically thought closely related to beeches, are treated as members of a separate family, the [[Nothofagaceae]] (which remains a member of the order [[Fagales]]). They are found throughout the [[Southern Hemisphere]] in Australia, New Zealand, [[New Guinea]], [[New Caledonia]], as well as [[Argentina]] and Chile (principally [[Patagonia]] and [[Tierra del Fuego]]).

===Species===
Species treated in Denk et al. (2024) and listed in [[Plants of the World Online|Plants of the World Online (POWO)]]:<ref name="Denk-2024" />
{| class="wikitable collapsible"
|-
! Image !! Name 
!Subgenus
!Status, systematic affinity!! Distribution 
!Accepted as species in POWO as of April 2023<ref name="POWO-2022">{{cite web |date=2022-05-07 |title=Fagus L. - Plants of the World Online |url=http://powo.science.kew.org/taxon/urn:lsid:ipni.org:names:30048723-2 |access-date=2023-04-24 |website=Plants of the World Online}}</ref>
|-
|
|''[[Fagus caspica]]'' {{Small|Denk & G.W.Grimm}} – Caspian beech
|''Fagus''
|New species described in 2024;<ref name="Denk-2024" /> first-diverging lineage within the Western Eurasian group
|[[Talysh Mountains|Talysch]] and [[Alborz|Elburz Mountains]], southeastern [[Azerbaijan]] and northern [[Iran]]
|Populations included in ''F. sylvatica'' subsp. ''orientalis''
|-
| ||''[[Fagus chienii]]'' {{small|[[Wan Chun Cheng|W.C.Cheng]]}}
|''Fagus''
|Possibly conspecific with ''F. lucida''<ref name="Denk-2003" />|| Probably extinct, described from a single location in China (Sichuan). Individuals recently collected at the type locality were morphologically and genetically indistinguishable from ''F. pashanica''.<ref>{{Cite journal |last1=Li |first1=Dan-Qi |last2=Jiang |first2=Lu |last3=Liang |first3=Hua |last4=Zhu |first4=Da-Hai |last5=Fan |first5=Deng-Mei |last6=Kou |first6=Yi-Xuan |last7=Yang |first7=Yi |last8=Zhang |first8=Zhi-Yong |date=2023-09-01 |title=Resolving a nearly 90-year-old enigma: The rare Fagus chienii is conspecific with F. hayatae based on molecular and morphological evidence |journal=Plant Diversity |volume=45 |issue=5 |pages=544–551 |doi=10.1016/j.pld.2023.01.003 |issn=2468-2659 |pmc=10625896 |pmid=37936819|bibcode=2023PlDiv..45..544L }}</ref>
|Yes
|-
|[[File:Fagus crenata leave in Mount Mominuka.jpg|120px]]||''[[Fagus crenata]]'' {{small|[[Carl Ludwig Blume|Blume]]}} – Siebold's beech or Japanese beech
|''Fagus''
|Widespread species; complex history connecting it to both the Western Eurasian group and the other East Asian species of subgenus ''Fagus''<ref name="Cardoni-2021" />||Japan; in the mountains of [[Kyushu]], [[Shikoku]] and [[Honshu]], down to sea-level in southern [[Hokkaido]].
|Yes
|-
|[[File:Fagus engleriana - Morris Arboretum - DSC00475.JPG|120px]]||''[[Fagus engleriana]]'' {{small|[[Karl Otto von Seemen|Seemen]] ex Diels}} – Chinese beech
|''Englerianae''
|Widespread species; continental sister species of ''F. japonica''<ref name="Denk-2005" /><ref name="Jiang-2022" /><ref name="Cardoni-2021" />||China; south of the [[Yellow River]]
|Yes
|-
|[[File:Fagus grandifolia JPG1Ms.jpg|120px]]||''[[Fagus grandifolia]]'' {{small|[[Ehrh.]]}} – American beech
|''Fagus''
|Widespread species; sister species of ''F. mexicana''<ref name="Jiang-2022" /><ref name="Cardoni-2021" />||Eastern North America; from E. Texas and N. Florida, United States, to the [[St. Lawrence River]], Canada at low to mid altitudes
|Yes, including Mexican beeches, ''F. mexicana''
|-
|[[File:Fagus hayatae 98412.jpg|120px]]||''[[Fagus hayatae]]'' {{small|Palib. ex Hayata}}
|''Fagus''
|Narrow [[Endemism|endemic]] species; forming a cryptic sister species pair with ''F. pashanica''<ref name="Cardoni-2021" /><ref name="Denk-2024" />||[[Taiwan]]; restricted to the mountains of northern Taiwan
|Yes
|-
|
|''Fagus hohenackeriana'' {{Small|Palib.}} – [[Rudolph Friedrich Hohenacker|Hohenacker]]'s or Caucasian beech
|''Fagus''
|Dominant tree species of the Pontic and [[Caucasus]] Mountains; intermediate between ''F. caspica'' and ''F. orientalis.''<ref name="Gömöry-2010">{{Cite journal |last1=Gömöry |first1=Dušan |last2=Paule |first2=Ladislav |date=2010-07-01 |title=Reticulate evolution patterns in western-Eurasian beeches |url=https://link.springer.com/article/10.1007/s00035-010-0068-y |journal=Botanica Helvetica |language=en |volume=120 |issue=1 |pages=63–74 |doi=10.1007/s00035-010-0068-y |bibcode=2010BotHe.120...63G |issn=1420-9063|url-access=subscription }}</ref><ref name="Gömöry-2018">{{Cite journal |last1=Gömöry |first1=Dušan |last2=Paule |first2=Ladislav |last3=Mačejovský |first3=Vladimír |date=2018-06-29 |title=Phylogeny of beech in western Eurasia as inferred by approximate Bayesian computation |url=https://pbsociety.org.pl/journals/index.php/asbp/article/view/asbp.3582 |journal=Acta Societatis Botanicorum Poloniae |language=en |volume=87 |issue=2 |page=3582 |doi=10.5586/asbp.3582 |bibcode=2018AcSBP..87.3582G |issn=2083-9480}}</ref><ref name="Kurz-2023">{{Cite journal |last1=Kurz |first1=Mirjam |last2=Kölz |first2=Adrian |last3=Gorges |first3=Jonas |last4=Pablo Carmona |first4=Beatriz |last5=Brang |first5=Peter |last6=Vitasse |first6=Yann |last7=Kohler |first7=Martin |last8=Rezzonico |first8=Fabio |last9=Smits |first9=Theo H. M. |last10=Bauhus |first10=Jürgen |last11=Rudow |first11=Andreas |last12=Kim Hansen |first12=Ole |last13=Vatanparast |first13=Mohammad |last14=Sevik |first14=Hakan |last15=Zhelev |first15=Petar |date=2023-03-01 |title=Tracing the origin of Oriental beech stands across Western Europe and reporting hybridization with European beech – Implications for assisted gene flow |url=https://linkinghub.elsevier.com/retrieve/pii/S0378112723000348 |journal=Forest Ecology and Management |volume=531 |pages=120801 |doi=10.1016/j.foreco.2023.120801 |bibcode=2023ForEM.53120801K |issn=0378-1127|hdl=20.500.11850/597076 |hdl-access=free }}</ref> Its genetic heterogeneity<ref name="Denk-2024" /><ref>{{Cite journal |last1=Sękiewicz |first1=Katarzyna |last2=Danelia |first2=Irina |last3=Farzaliyev |first3=Vahid |last4=Gholizadeh |first4=Hamid |last5=Iszkuło |first5=Grzegorz |last6=Naqinezhad |first6=Alireza |last7=Ramezani |first7=Elias |last8=Thomas |first8=Peter A. |last9=Tomaszewski |first9=Dominik |last10=Walas |first10=Łukasz |last11=Dering |first11=Monika |date=2022 |title=Past climatic refugia and landscape resistance explain spatial genetic structure in Oriental beech in the South Caucasus |journal=Ecology and Evolution |language=en |volume=12 |issue=9 |pages=e9320 |doi=10.1002/ece3.9320 |issn=2045-7758 |pmc=9490144 |pmid=36188519|bibcode=2022EcoEv..12E9320S }}</ref> may be indicative for ongoing speciation processes.
|Northeastern Anatolia ([[Pontic Mountains]], [[Kaçkar Mountains]]) and Caucasus region ([[Lesser Caucasus|Lesser]] and [[Greater Caucasus]], Georgia, [[Armenia]], [[North Caucasus|Ciscaucasia]]; down to sea-level in southwestern Georgia)
|No, populations included in ''F. sylvatica'' subsp. ''orientalis''
|-
|[[File:Forest in Tanzawa 08.jpg|120px]]||''[[Fagus japonica]]'' {{small|[[Maxim.]]}}
|''Englerianae''
|Widespread species; insular sister species of ''F. engleriana''<ref name="Cardoni-2021" />''<ref name="Denk-2005" /><ref name="Jiang-2022" />''||Japan; Kyushu, Shikoku and Honshu from sea-level up to c. 1500 m [[Height above mean sea level|a.s.l.]]
|Yes
|-
|
|[[Fagus longipetiolata]] {{Small|Seemen}}
|''Fagus''
|[[Sympatry|Sym-]] to [[Parapatry|parapatric]] with ''F. lucida'' and ''F. pashanica'', and sharing alleles with both species in addition to alleles indicating a sister relationship with the Japanese ''F. crenata''.<ref name="Cardoni-2021" /><ref name="Jiang-2022" />
|China, south of the Yellow River, into N. [[Vietnam]]; in montane areas up to 2400 m a.s.l.<ref>{{Cite web |title=Fagus longipetiolata in Flora of China @ efloras.org |url=http://www.efloras.org/florataxon.aspx?flora_id=2&taxon_id=200006255 |access-date=2024-10-24 |website=www.efloras.org}}</ref>
|Replaced by ''F. sinensis''
|-
|[[File:Fagus lucida Buk 2020-07-18 01.jpg|120px]]||''[[Fagus lucida]]'' {{small|Rehder & [[E.H.Wilson]]}}
|''Fagus''
|Rare species; closest relatives are ''F. crenata''<ref name="Cardoni-2021" /><ref name="Denk-2005" /><ref name="Denk-2003" /> and ''F. longipetiolata''<ref name="Cardoni-2021" /><ref name="Jiang-2022" />||China; south of the Yellow River in montane areas between 800 and 2000 m a.s.l.<ref>{{Cite web |title=Fagus lucida in Flora of China @ efloras.org |url=http://www.efloras.org/florataxon.aspx?flora_id=2&taxon_id=200006256 |access-date=2024-10-24 |website=www.efloras.org}}</ref>
|Yes
|-
|
|''Fagus mexicana'' {{Small|Martínez}}
|''Fagus''
|Narrow endemic sister species of ''F. grandifolia. F. mexicana'' differs from ''F. grandifolia'' by its slender leaves and less-evolved but more polymorphic set of alleles (higher level of [[Zygosity|heterozygosity]])<ref name="Cardoni-2021" /><ref name="Jiang-2022" />
|[[Hidalgo (state)|Hidalgo]], Mexico; at 1400–2000 m a.s.l. as an element of the subtropical montane mesophilic forest"([https://www.gob.mx/conabio/prensa/bosques-mesofilos-de-montana-de-mexico?idiom=es bosque mesófilo de montaña]) superimposing the tropical lowland rainforests.
|No, populations included in ''F. grandifolia''
|-
| ||''[[Fagus multinervis]]'' {{small|Nakai}}
|''Englerianae''
|Narrow endemic species, first diverging lineage within subgenus ''Englerianae''<ref name="Cardoni-2021" /><ref name="Jiang-2022" />|| South Korea ([[Ulleungdo]])
|Yes
|-
|[[File:Fagus orientalis near Fioletovo village, Armenia S-N 04.jpg|120px]] ||''[[Fagus orientalis]]'' {{small|[[Vladimir Ippolitovich Lipsky|Lipsky]]}} – Oriental beech (in a narrow sense)
|''Fagus''
|Sister species of ''F. sylvatica''<ref name="Gömöry-2018" /><ref name="Kurz-2023" />||Southeastern Europe (SE [[Bulgaria]], NE [[Greece]], [[East Thrace|European Turkey]]) and adjacent northwestern Asia (NW and N [[Anatolia]]) 
|No, treated as subspecies of ''F. sylvatica''
|-
| ||''[[Fagus pashanica]]'' {{small|C.C.Yang}} 
|''Fagus''
|Continental sister species of ''F. hayatae'', with a set of alleles that puts it closer to ''F. longipetiolata'' and ''F. crenata'' than its insular sister.|| China (Hubei, Hunan, Shaanxi, Sichuan, Zhejiang), at 1300–2300 m a.s.l.(eFlora of China, as ''F. hayatae''<ref>{{Cite web |title=Fagus hayatae in Flora of China @ efloras.org |url=http://www.efloras.org/florataxon.aspx?flora_id=2&taxon_id=200006254 |access-date=2024-10-24 |website=www.efloras.org}}</ref>) 
|Yes
|-
| ||''[[Fagus sinensis]]'' {{small|Oliv.}} 
|''Fagus''
|Invalid; the original material included material from two much different species: ''F. engleriana'' and ''F. longipetiolata''<ref name="Denk-2024" /><ref name="Denk-2003" />|| China (Hubei), Vietnam
|Yes, erroneously used as older synonym of ''F. longipetiolata''
|-
|[[File:Fagus sylvatica 019.jpg|120px]] ||''[[Fagus sylvatica]]'' {{small|[[L.]]}} – European beech
|''Fagus''
|Sister species of and closely related to ''F. orientalis''<ref name="Gömöry-2018" /><ref name="Kurz-2023" />|| Europe
|Yes
|-
|}

===Natural and potential hybrids===
{| class="wikitable collapsible"
|-
! Image !! Name !! Parentage 
!Status!!Distribution 
|-
|
|[[Fagus × moesiaca|''Fagus'' (''×'') ''moesiaca'']] {{Small|(K. Malý) Czeczott}}
|''F. sylvatica'' × ''F. orientalis''
|No evidence so far for hybrid origin. All individuals addressed as ''F. moesiaca'' included in genetic studies fell within the variation of ''F. sylvatica.''<ref name="Denk-2005" /><ref>{{Cite journal |last1=Ulaszewski |first1=Bartosz |last2=Meger |first2=Joanna |last3=Mishra |first3=Bagdevi |last4=Thines |first4=Marco |last5=Burczyk |first5=Jarosław |date=2021 |title=Complete Chloroplast Genomes of Fagus sylvatica L. Reveal Sequence Conservation in the Inverted Repeat and the Presence of Allelic Variation in NUPTs |journal=Genes |language=en |volume=12 |issue=9 |pages=1357 |doi=10.3390/genes12091357 |doi-access=free |issn=2073-4425 |pmc=8468245 |pmid=34573338}}</ref> They may represent a lowland ecotype of ''F. sylvatica.''<ref name="Denk-2024" /><ref>{{Cite journal |last=Denk |first=Th. |date=January 1999 |title=The taxonomy of Fagus in western Eurasia. 2: Fagus sylvatica subsp. sylvatica |url=https://onlinelibrary.wiley.com/doi/10.1002/fedr.19991100510 |journal=Feddes Repertorium |language=en |volume=110 |issue=5–6 |pages=381–412 |doi=10.1002/fedr.19991100510 |issn=0014-8962|url-access=subscription }}</ref>
Erroneously synonymized by some authors (e.g. POWO) with the Crimean ''F. × taurica,'' from which it differs morphologically and genetically.
|Southeastern [[Balkans]]
|-
|
|''Fagus okamotoi'' {{Small|Shen}}
|''F. crenata'' × ''F. japonica'' ?
|Unique phenotype, described from an area in which ''F. crenata'' and ''F. japonica'' are sympatric. So far, there is no genetic evidence for ongoing gene flow between the two Japanese species, which belong to different subgeneric lineages.
|[[Kantō region|Kanto]], eastern Honshu
|-
|[[File:Bukva 2.jpg|120px]] ||''[[Fagus × taurica]]'' {{small|[[Popl.]]}} – Crimean beech|| ''F. sylvatica'' × ''F. orientalis'' s.l.
|Hybrid status not yet tested by genetic data; according to [[Isozyme|isoenzyme]] profiles a less-evolved, relict population of ''F. sylvatica'' or intermediate between ''F. sylvatica'' and the species complex historically addressed as Oriental beech (''F. orientalis'' in a broad sense)<ref name="Gömöry-2010" />||Crimean peninsula
|-
|}

===Phylogeny===

A cladogram of 11 beech species is shown below.<ref>{{cite journal |author1=Jiang, Lu |display-authors=etal |title=Phylogeny and biogeography of Fagus (Fagaceae) based on 28 nuclear single/low-copy loci |journal=Journal of Systematics and Evolution |date=10 October 2020 |volume=60 |issue=4 |pages=759–772 |doi=10.1111/jse.12695 |url=https://onlinelibrary.wiley.com/doi/abs/10.1111/jse.12695|url-access=subscription }}</ref>

{{clade
|label1='''''Fagus'''''
|1={{clade
   |label1=subg. ''Engleriana''
   |1={{clade
      |1=''F. multinervis''
      |2={{clade
         |1=''F. engleriana''
         |2=''F. japonica''
         }}
      }}
   |label2=subg. ''Fagus''
   |2={{clade
      |label1=sect. ''Grandifolia''
      |1={{clade
         |1=''F. grandifolia''
         |2=''F. mexicana''
         }}
      |2={{clade
         |label1=sect. ''Fagus''
         |1={{clade
            |1=''F. orientalis''
            |2=''F. sylvatica''
            }}
         |label2=sect. ''Lucida''
         |2={{clade
            |1=''F. hayatae''
            |2={{clade
               |1=''F. crenata''
               |2={{clade
                  |1=''F. longipetiolata''
                  |2=''F. lucida''
                  }}
               }}
            }}
         }}
      }}
   }}
}}

===Fossil species===
Numerous species have been named globally from the fossil record spanning from the [[Cretaceous]] to the [[Pleistocene]].<ref name="IFPNI-2023">{{cite web |url=http://ifpni.org/genus.htm?id=3EE9EA96-C4DC-4621-B6EB-697227CF797B |website=The International Fossil Plant Names Index |title=''Fagus'' |accessdate=6 Feb 2023}}</ref> 
{{div col}}
*†''[[Fagus aburatoensis]]'' {{small|Tanai, 1951}}<ref name="Tanai-1952">{{cite journal |last1=Tanai |first1=T. |title=Des fossiles végétaux dans le bassin houiller de Nishitagawa, Préfecture de Yamagata, Japon |journal=Japanese Journal of Geology and Geography |volume=22 |pages=119–135}}</ref> 
*†''[[Fagus alnitifolia]]'' {{small|[[Arthur Hollick|Hollick]]}}<ref name="Brown-1937">{{cite report |last1=Brown |first1=R. W. |year=1937 |title=Additions to some fossil floras of the Western United States |series=Professional Paper |publisher=United States Geological Survey |volume=186 |pages=163–206 |doi=10.3133/pp186J |url=https://pubs.usgs.gov/pp/0186j/report.pdf}}</ref>
*†''[[Fagus altaensis]]'' {{small|Kornilova & Rajushkina, 1979}}
*†''[[Fagus ambigua]]'' {{small|(Massalongo) Massalongo, 1853}}
*†''[[Fagus angusta]]'' {{small|Andreánszky, 1959}}
*†''[[Fagus antipofii]]'' {{small|Heer, 1858}}
*†''[[Fagus aperta]]'' {{small|Andreánszky, 1959}}
*†''[[Fagus arduinorum]]'' {{small|Massalongo, 1858}}
*†''[[Fagus aspera (Berry) Brown|Fagus aspera]]'' {{small|(Berry) Brown, 1944}}
*†''[[Fagus aspera (Chelebaeva)|Fagus aspera]]'' {{small|Chelebaeva, 2005}} (jr homonym)
*†''[[Fagus atlantica]]'' {{small|Unger, 1847}}
*†''[[Fagus attenuata]]'' {{small|Göppert, 1855}}
*†''[[Fagus aurelianii]]'' {{small|Marion & Laurent, 1895}}
*†''[[Fagus australis]]'' {{small|Oliver, 1936}}
*†''[[Fagus betulifolia]]'' {{small|Massalongo, 1858}}
*†''[[Fagus bonnevillensis]]'' {{small|Chaney, 1920}}
*†''[[Fagus castaneifolia]]'' {{small|Unger, 1847}}
*†''[[Fagus celastrifolia]]'' {{small|Ettingshausen, 1887}}
*†''[[Fagus ceretana]]'' {{small|(Rérolle) Saporta, 1892}}
*†''[[Fagus chamaephegos]]'' {{small|Unger, 1861}}
*†''[[Fagus chankaica]]'' {{small|Alexeenko, 1977}}
*†''[[Fagus chiericii]]'' {{small|Massalongo, 1858}}
*†''[[Fagus chinensis]]'' {{small|Li, 1978}}
*†''[[Fagus coalita]]'' {{small|Rylova, 1996}}
*†''[[Fagus cordifolia]]'' {{small|Heer, 1883}}
*†''[[Fagus cretacea]]'' {{small|Newberry, 1868}}
*†''[[Fagus decurrens]]'' {{small|Reid & Reid, 1915}}
*†''[[Fagus dentata]]'' {{small|Göppert, 1855}}
*†''[[Fagus deucalionis]]'' {{small|Unger, 1847}}
*†''[[Fagus dubia (Mirb)|Fagus dubia]]'' {{small|Mirb, 1822}}
*†''[[Fagus dubia (Watelet)|Fagus dubia]]'' {{small|Watelet, 1866}} (jr homonym)
*†''[[Fagus echinata]]'' {{small|Chelebaeva, 2005}}
*†''[[Fagus eocenica]]'' {{small|Watelet, 1866}}
*†''[[Fagus etheridgei]]'' {{small|Ettingshausen, 1891}}
*†''[[Fagus ettingshausenii]]'' {{small|Velenovský, 1881}}
*†''[[Fagus europaea]]'' {{small|Schwarewa, 1960}}
*†''[[Fagus evenensis]]'' {{small|Chelebaeva, 1980}}
*†''[[Fagus faujasii]]'' {{small|Unger, 1850}}
*†''[[Fagus feroniae]]'' {{small|Unger, 1845}}
*†''[[Fagus florinii]]'' {{small|Huzioka & Takahashi, 1973}}
*†''[[Fagus forumlivii]]'' {{small|Massalongo, 1853}}
*†''[[Fagus friedrichii]]'' {{small|Grímsson & Denk, 2005}}
*†''[[Fagus gortanii]]'' {{small|Fiori, 1940}}
*†''[[Fagus grandifoliiformis]]'' {{small|Panova, 1966}}
*†''[[Fagus gussonii]]'' {{small|Massalongo, 1858}}
*†''[[Fagus haidingeri]]'' {{small|Kováts, 1856}}
*†''[[Fagus herthae]]'' {{small|(Unger) Iljinskaja, 1964}}
*†''[[Fagus hitchcockii]]'' {{small|Lesquereux, 1861}}
*†''[[Fagus hondoensis]]'' {{small|(Watari) Watari, 1952}}
*†''[[Fagus hookeri]]'' {{small|Ettingshausen, 1887}}
*†''[[Fagus horrida]]'' {{small|Ludwig, 1858}}
*†''[[Fagus humata]]'' {{small|Menge & Göppert, 1886}}
*†''[[Fagus idahoensis]]'' {{small|Chaney & Axelrod, 1959}}
*†''[[Fagus inaequalis]]'' {{small|Göppert, 1855}}
*†''[[Fagus incerta]]'' {{small|(Massalongo) Massalongo, 1858}}
*†''[[Fagus integrifolia]]'' {{small|Dusén, 1899}}
*†''[[Fagus intermedia]]'' {{small|Nathorst, 1888}}
*†''[[Fagus irvajamensis]]'' {{small|Chelebaeva, 1980}}
*†''[[Fagus japoniciformis]]'' {{small|Ananova, 1974}}
*†''[[Fagus japonicoides]]'' {{small|Miki, 1963}}
*†''[[Fagus jobanensis]]'' {{small|Suzuki, 1961}}
*†''[[Fagus jonesii]]'' {{small|Johnston, 1892}}
*†''[[Fagus juliae]]'' {{small|Jakubovskaya, 1975}}
*†''[[Fagus kitamiensis]]'' {{small|Tanai, 1995}}
*†''[[Fagus koraica]]'' {{small|Huzioka, 1951}}
*†''[[Fagus kraeuselii]]'' {{small|Kvaček & Walther, 1991}}
*†''[[Fagus kuprianoviae]]'' {{small|Rylova, 1996}}
*†''[[Fagus lancifolia]]'' {{small|Heer, 1868}} (nomen nudum)
*†''[[Fagus langevinii]]'' {{small|Manchester & Dillhoff, 2004}}<ref name="Manchester-2004">{{cite journal |last1=Manchester |first1=S. R. |last2=Dillhoff |first2=R. M. |title=''Fagus'' (Fagaceae) fruits, foliage, and pollen from the Middle Eocene of Pacific Northwestern North America |journal=Canadian Journal of Botany |volume=82 |issue=10 |pages=1509–1517 |doi=10.1139/b04-112|year=2004 |bibcode=2004CaJB...82.1509M }}</ref>
*†''[[Fagus laptoneura]]'' {{small|Ettingshausen, 1895}}
*†''[[Fagus latissima]]'' {{small|Andreánszky, 1959}}
*†''[[Fagus leptoneuron]]'' {{small|Ettingshausen, 1893}}
*†''[[Fagus macrophylla]]'' {{small|Unger, 1854}}
*†''[[Fagus maorica]]'' {{small|Oliver, 1936}}
*†''[[Fagus marsillii]]'' {{small|Massalongo, 1858}}
*†''[[Fagus menzelii]]'' {{small|Kvaček & Walther, 1991}}
*†''[[Fagus microcarpa]]'' {{small|Miki, 1933}}
*†''[[Fagus miocenica]]'' {{small|Ananova, 1974}}
*†''[[Fagus napanensis]]'' {{small|Iljinskaja, 1982}}
*†''[[Fagus nelsonica]]'' {{small|Ettingshausen, 1887}}
*†''[[Fagus oblonga (Suzuki)|Fagus oblonga]]'' {{small|Suzuki, 1959}}
*†''[[Fagus oblonga (Andreánszky)|Fagus oblonga]]'' {{small|Andreánszky, 1959}}
*†''[[Fagus obscura]]'' {{small|Dusén, 1908}}
*†''[[Fagus olejnikovii]]'' {{small|Pavlyutkin, 2015}}
*†''[[Fagus orbiculatum]]'' {{small|Lesquereux, 1892}}
*†''[[Fagus orientaliformis]]'' {{small|Kul'kova}}
*†[[Fagus orientalis|''Fagus orientalis'' var ''fossilis'']] {{small|Kryshtofovich & Baikovskaja, 1951}}
*†[[Fagus orientalis|''Fagus orientalis'' var ''palibinii'']] {{small|Iljinskaja, 1982}}
*†''[[Fagus pacifica]]'' {{small|Chaney, 1927}}
*†''[[Fagus palaeococcus]]'' {{small|Unger, 1847}}
*†''[[Fagus palaeocrenata]]'' {{small|Okutsu, 1955}}
*†''[[Fagus palaeograndifolia]]'' {{small|Pavlyutkin, 2002}}
*†''[[Fagus palaeojaponica]]'' {{small|Tanai & Onoe, 1961}}
*†''[[Fagus pittmanii]]'' {{small|Deane, 1902}}
*†''[[Fagus pliocaenica]]'' {{small|Geyler & Kinkelin, 1887}} (jr homonym)
*†''[[Fagus pliocenica]]'' {{small|Saporta, 1882}}
*†''[[Fagus polycladus]]'' {{small|Lesquereux, 1868}}
*†''[[Fagus praelucida]]'' {{small|Li, 1982}}
*†''[[Fagus praeninnisiana]]'' {{small|Ettingshausen, 1893}}
*†''[[Fagus praeulmifolia]]'' {{small|Ettingshausen, 1893}}
*†''[[Fagus prisca]]'' {{small|Ettingshausen, 1867}}
*†''[[Fagus pristina]]'' {{small|Saporta, 1867}}
*†''[[Fagus producta]]'' {{small|Ettingshausen, 1887}}
*†''[[Fagus protojaponica]]'' {{small|Suzuki, 1959}}
*†''[[Fagus protolongipetiolata]]'' {{small|Huzioka, 1951}}
*†''[[Fagus protonucifera]]'' {{small|Dawson, 1884}}
*†''[[Fagus pseudoferruginea]]'' {{small|Lesquereux, 1878}}
*†''[[Fagus pygmaea]]'' {{small|Unger, 1861}}
*†''[[Fagus pyrrhae]]'' {{small|Unger, 1854}}
*†''[[Fagus salnikovii]]'' {{small|Fotjanova, 1988}}
*†''[[Fagus sanctieugeniensis]]'' {{small|Hollick, 1927}}
*†''[[Fagus saxonica]]'' {{small|Kvaček & Walther, 1991}}
*†''[[Fagus schofieldii]]'' {{small|Mindell, Stockey, & Beard, 2009}}
*†''[[Fagus septembris]]'' {{small|Chelebaeva, 1991}}
*†''[[Fagus shagiana]]'' {{small|Ettingshausen, 1891}}
*†''[[Fagus stuxbergii]]'' {{small|Tanai, 1976}}
*†''[[Fagus subferruginea]]'' {{small|Wilf ''et al.'', 2005}}<ref name="Wilf-2005">{{cite journal |last1=Wilf |first1=P. |last2=Johnson |first2=K.R. |last3=Cúneo |first3=N.R. |last4=Smith |first4=M.E. |last5=Singer |first5=B.S. |last6=Gandolfo |first6=M.A. |year=2005 |title=Eocene Plant Diversity at Laguna del Hunco and Río Pichileufú, Patagonia, Argentina |url=https://www.researchgate.net/publication/312253100 |journal=[[The American Naturalist]] |volume=165 |issue=6 |pages=634–650 |access-date=2019-02-22|doi=10.1086/430055 |pmid=15937744 |bibcode=2005ANat..165..634W |s2cid=3209281 }}</ref>
*†''[[Fagus succinea]]'' {{small|Göppert & Menge, 1853}}
*†[[Fagus sylvatica|''Fagus sylvatica'' var ''diluviana'']] {{small|Saporta, 1892}}
*†[[Fagus sylvatica|''Fagus sylvatica'' var ''pliocenica'']] {{small|Saporta, 1873}}
*†''[[Fagus tenella]]'' {{small|Panova, 1966}}
*†''[[Fagus uemurae]]'' {{small|Tanai, 1995}}
*†''[[Fagus uotanii]]'' {{small|Huzioka, 1951}}
*†''[[Fagus vivianii]]'' {{small|Unger, 1850}}
*†''[[Fagus washoensis]]'' {{small|LaMotte, 1936}}
{{div col end}}
Fossil species formerly placed in ''Fagus'' include:<ref name="IFPNI-2023"/>
{{div col}}
*†''[[Alnus paucinervis]]'' {{small|(Borsuk) Iljinskaja}}
*†''[[Castanea abnormalis]]'' {{small|(Fotjanova) Iljinskaja}}
*†''[[Fagopsis longifolia]]'' {{small|(Lesquereux) Hollick}}
*†''[[Fagopsis undulata]]'' {{small|(Knowlton) Wolfe & Wehr}}
*†''[[Fagoxylon grandiporosum]]'' {{small|(Beyer) Süss}}
*†''[[Fagus-pollenites parvifossilis]]'' {{small|(Traverse) Potonié}}
*†''[[Juglans ginannii]]'' {{small|Massalongo}} (new name for ''F. ginannii'')
*†''[[Nothofagaphyllites novae-zealandiae]]'' {{small|(Oliver) Campbell}}
*†''[[Nothofagus benthamii]]'' {{small|(Ettingshausen) Paterson}}
*†''[[Nothofagus dicksonii]]'' {{small|(Dusén) Tanai}}
*†''[[Nothofagus lendenfeldii]]'' {{small|(Ettingshausen) Oliver}}
*†''[[Nothofagus luehmannii]]'' {{small|(Deane) Paterson}}
*†''[[Nothofagus magelhaenica]]'' {{small|(Ettingshausen) Dusén}}
*†''[[Nothofagus maidenii]]'' {{small|(Deane) Chapman}}
*†''[[Nothofagus muelleri]]'' {{small|(Ettingshausen) Paterson}}
*†''[[Nothofagus ninnisiana]]'' {{small|(Unger) Oliver}}
*†''[[Nothofagus risdoniana]]'' {{small|(Ettingshausen) Paterson}}
*†''[[Nothofagus ulmifolia]]'' {{small|(Ettingshausen) Oliver}}
*†''[[Nothofagus wilkinsonii]]'' {{small|(Ettingshausen) Paterson}}
*†''[[Trigonobalanus minima]]'' {{small|(M. Chandler) Mai}}
{{div col end}}

=== Etymology ===
The name of the tree in Latin, ''fagus'' (from whence the [[generic epithet]]), is cognate with English "beech" and of [[Indo-European language|Indo-European]] origin, and played an important role in early debates on the geographical origins of the [[Proto-Indo-Europeans|Indo-European people]], the [[beech argument]]. [[Greek language|Greek]] φηγός (figós) is from the same root, but the word was transferred to the oak tree (e.g. Iliad 16.767) as a result of the absence of beech trees in southern [[Greece]].<ref>Robert Beekes, Etymological Dictionary of Greek, Leiden and Boston 2010, pp. 1565–6</ref>