identifier	taxonID	type	CVterm	format	language	title	description	additionalInformationURL	UsageTerms	rights	Owner	contributor	creator	bibliographicCitation
B10687A8FFDEEB06FF74FD08FBA9FB12.text	B10687A8FFDEEB06FF74FD08FBA9FB12.taxon	http://purl.org/dc/dcmitype/Text	http://rs.tdwg.org/ontology/voc/SPMInfoItems#GeneralDescription	text/html	en	Fagus	<div><p>Fagus L. subg. Fagus – Type (designated by Green 1929: 189): Fagus sylvatica L., Sp. Pl. 2: 998. 1753.</p><p>Molecular diagnosis — The subgenus differs consistently from all species of Fagus subg. Englerianae in any sufficiently divergent nuclear marker sequenced so far (Denk &amp; al. 2002, 2005; Renner &amp; al. 2016; Cardoni &amp; al. 2022). Its ITS variants belong to Lineages II–IV as defined in Denk &amp; al. (2005); the sequenced part of the Crabs Claw (CRC) gene (~1650 bps) and the 2 nd intron of the Leafy gene (LFY, up to ~1300 bps) include 14 subgenus-sorted SNPs (CRC pos. 212 [C vs T in F. subg. Englerianae], 714 [C↔T], 904 [C↔A], 1148 [A↔T/Y] and 1329 [T↔G]; LFY pos. 241 [A↔C], 398, 402, 465 [all G↔A], 507 [T↔A], 529 [C↔T], 1031 [T↔G], 1206 [A↔G] and 1246 [T↔A]; according reference matrices are included in the SDA, file RefMatrixCRCLFYSpCons.nex). Additional subgenus-diagnostic SNPs can be found in 21 of the 28 nuclear loci sequenced by Jiang &amp; al. (2022; cf. supplement to Cardoni &amp; al. 2022). Plastomes are divergent but geographically sorted and reflect two independent origins: Lineage I in North America; sibling lineages Lineage IV in East Asia and Lineage V in western Eurasia; see Fig. 1) The exception are populations of the Japanese species F. crenata comprising individuals that may carry near-private haplotypes of Lineage II (supplementary content, file Genotypification.xlsx, sheet PlstmDissim; including information from upcoming complete plastome data; Worth &amp; al. 2021, work in progress).</p><p>Morphological diagnosis — Trees; buds sessile; leaves thick-chartaceous, abaxial leaf surface commonly smooth or papillate ( Fagus longipetiolata), wax ornamentation on abaxial leaf surface missing or present ( F. longipetiolata), size of stomata usually large, small in F. hayatae Palib., F. pashanica C. C. Yang, and F. grandifolia, subsidiary cells of stomata usually actinocytic to cyclocytic, anomocytic in F. grandifolia, leaf margin smooth or serrate; cupule peduncle short to long; pollen usually large, intermediate in F. hayatae, colpi usually short with more or less acute apex, or long and narrow with rectangular apex in F. grandifolia and occasionally in F. longipetiolata .</p><p>Species — Twelve: Fagus sylvatica, F. orientalis, F. hohenackeriana, F. caspica sp. nov. in western Eurasia (west to east); F. chienii W. C. Cheng (†?), F. crenata, F. hayatae, F. longipetiolata, F. pashanica, F. lucida in East Asia; F. grandifolia, F. mexicana MartÍnez in North America.</p><p>Remarks — Members of Fagus subg. Fagus can be traced in the fossil record based on their pollen and leaf-anatomical similarities with one or several modern-day species (Denk &amp; Grimm 2009; Renner &amp; al. 2016; Worth &amp; al., work in progress). The oldest fossils representing this modern subgeneric lineage are cupules and leaves from the Eocene-Oligocene boundary, Northeast Asia (Pavlyutkin &amp; al. 2014; see also Denk &amp; Grimm 2009). Any molecular-phylogenetic tree analysis (e.g. Denk &amp; al. 2005; Jiang &amp; al. 2022) relying on sufficiently variable nuclear data will produce a prominent split with high (BS ≥ 70, PP ≥ 0.9) to unambiguous (BS = 100, PP = 1.0) support between the subgenera irrespective of the optimality criterion used for tree-inference. Newly sequenced individuals can be easily placed in either subgenus using e.g. the evolutionary placement algorithm implemented in RAxML 8 and its successor RAxML-ng. In contrast, any plastome data requires in-depth analysis and, in some cases, may fail to elucidate the subgeneric affinity.</p></div>	https://treatment.plazi.org/id/B10687A8FFDEEB06FF74FD08FBA9FB12	Public Domain	No known copyright restrictions apply. See Agosti, D., Egloff, W., 2009. Taxonomic information exchange and copyright: the Plazi approach. BMC Research Notes 2009, 2:53 for further explanation.		Plazi	Denk, Thomas;Grimm, Guido W.;Cardoni, Simone;Csilléry, Katalin;Schulze, Mirjam Kurz Ernst-Detlef;Simeone, Marco Cosimo;Worth, James R. P.	Denk, Thomas, Grimm, Guido W., Cardoni, Simone, Csilléry, Katalin, Schulze, Mirjam Kurz Ernst-Detlef, Simeone, Marco Cosimo, Worth, James R. P. (2024): A subgeneric classification of Fagus (Fagaceae) and revised taxonomy of western Eurasian beeches. Willdenowia 54: 151-181, DOI: 10.3372/wi.54.54301, URL: https://doi.org/10.3372/wi.54.54301
B10687A8FFDEEB00FC89FB08FDFDFB02.text	B10687A8FFDEEB00FC89FB08FDFDFB02.taxon	http://purl.org/dc/dcmitype/Text	http://rs.tdwg.org/ontology/voc/SPMInfoItems#GeneralDescription	text/html	en	Fagus (Englerianae) Denk	<div><p>Fagus subg. Englerianae Denk &amp; G. W. Grimm, subg. nov.</p><p>Type: Fagus engleriana Seemen ex Diels in Bot. Jahrb. Syst. 29: 285. 1900.</p><p>Molecular diagnosis — The subgenus differs consistently from all species of Fagus subg. Fagus in any sufficiently divergent nuclear marker sequenced so far (Denk &amp; al. 2002, 2005; Renner &amp; al. 2016; Cardoni &amp; al. 2022). Its polymorphic and notably divergent ITS variants belong to Lineage I as defined in Denk &amp; al. (2005); the sequenced part of the Crabs Claw (CRC) gene and the 2 nd intron of the Leafy gene (LFY) include 14 subgenus-sorted SNPs (see above) in addition to several subgenus-restricted length-polymorphic patterns (see supplementary content, file Genotypification.xlsx, sheets CRC LP-patterns, LFY LP-patterns): an AC tetramer at pos. 1634ff in the CRC reference alignment; a 7 nt-long duplication at pos. 199ff, 45 nt-long deletion at pos. 573ff, and diagnostic oligonucleotide motives at pos. 671–696 and 737–764. Additional subgenus-diagnostic SNPs can be found in 19 of the 28 nuclear loci sequenced by Jiang &amp; al. (2022; cf. supplement to Cardoni &amp; al. 2022, data S5): in P4 at reference alignment (SDA, file RefMatrixJiangEtAlNcLoci.nex) positions 296, 321, 361, 504; P12—pos. 50, 230, 290, 590, 695; P14—pos. 106, 159, 195, 492; P21—pos. 420, 746, 793; P28—pos. 53/54: TC dinucleotide ↔ AT, AC, GC in F. subg. Fagus, pos. 135; P37—pos. 7; P42—pos. 96, 239, 274, 308, 409, 453, 649, 665; P48—pos. 145, 241, 262, 287; P52—71, 86, 90, 165, 243, 272, 407, 455; P54—pos. 82, 313, 616, 683, 703; P69—pos. 85, 130, 204, 251, 267, 406, 475, 542, 656, 737; P72—pos. 40, 91, 222, 306, 334, 387, 412, 415f (TT dinucleotide ↔ CA in F. subg. Fagus), 593; P97—pos. 236, 305, 394, 427, 467, 684 (C↔T/G); P98—pos. 461, 509; F128—pos. 272, 297, 406, 448, 522, 637, 661; F159—pos. 42, 252; F253—pos. 47, 72, 133, 140, 177; F286—pos. 58, 70, 133, 281; F289—pos. 106, 159, 195, 492; subgenus-diagnostic indels and oligonucleotide motives (including subgenus-restricted allelic variation) can be found in P42—GTCTA at pos. 619ff ↔ AG in F. subg. Fagus); P48—pos. 544–546: CGT/TGT vs CTG/CGG; P52—pos. 43–54: CAG-tetramer in F. subg. Englerianae, dimer F. subg. Fagus; P69—TATA at pos. 704–709 vs TAYAAA; F253—GGA at pos. 90ff ↔ GGGA in F. subg. Fagus .</p><p>Morphological diagnosis — Multi-stemmed or lowbranching trees; buds stipitate; leaves thin-chartaceous, abaxial leaf surface papillate, abaxial leaf surface with conspicuous wax ornamentation, size of stomata small, subsidiary cells of stomata anomocytic, leaf margin usually without teeth; cupule peduncle medium-long to long; pollen small, colpi long and narrow with rectangular apex.</p><p>Species — Three: Fagus engleriana, F. japonica, F. multinervis Makai; all of which are restricted to East Asia.</p><p>Remarks — The name Fagus subg. Englerianae was proposed by the doctoral thesis of Shen (1992) but has not been effectively published. The pollen of modern-day species of F. subg. Englerianae has to be treated as (sym) plesiomorphic (cf. Denk 2003) while leaf anatomical features allow to trace this subgeneric lineage back to the late Eocene, western Japan (Uemura 2002; see also Denk &amp; Grimm 2009).</p><p>Revision of Fagus in western Eurasia</p></div>	https://treatment.plazi.org/id/B10687A8FFDEEB00FC89FB08FDFDFB02	Public Domain	No known copyright restrictions apply. See Agosti, D., Egloff, W., 2009. Taxonomic information exchange and copyright: the Plazi approach. BMC Research Notes 2009, 2:53 for further explanation.		Plazi	Denk, Thomas;Grimm, Guido W.;Cardoni, Simone;Csilléry, Katalin;Schulze, Mirjam Kurz Ernst-Detlef;Simeone, Marco Cosimo;Worth, James R. P.	Denk, Thomas, Grimm, Guido W., Cardoni, Simone, Csilléry, Katalin, Schulze, Mirjam Kurz Ernst-Detlef, Simeone, Marco Cosimo, Worth, James R. P. (2024): A subgeneric classification of Fagus (Fagaceae) and revised taxonomy of western Eurasian beeches. Willdenowia 54: 151-181, DOI: 10.3372/wi.54.54301, URL: https://doi.org/10.3372/wi.54.54301
B10687A8FFD8EB1DFF74FA6BFB8CFAB2.text	B10687A8FFD8EB1DFF74FA6BFB8CFAB2.taxon	http://purl.org/dc/dcmitype/Text	http://rs.tdwg.org/ontology/voc/SPMInfoItems#GeneralDescription	text/html	en	Fagus sylvatica fm. moesiaca K. Maly	<div><p>= Fagus sylvatica f. moesiaca K. Malý in Ascherson &amp;</p><p>Graebner, Syn. Mitteleur. Fl. 4: 438. 1911 ≡ Fagus moesiaca (K. Malý) Czeczott in Roczn. Polsk. Towarz. Dendrol. 5: 52. 1933. – Lectotype (designated here): Bulgaria, supra pagum Tvierdica [=Твърдица,</p><p>Tvrditsa] (inter Sliven et Elena), in monte Cumerna,</p><p>c. 950 m, fruct., 1927, K. Michoff, det. H. Czeczott</p><p>(WA [WA00000166143 Fig. 10]); isolectotype: WA</p><p>[WA00000166142]). See POWO (2023) for other heterotypic synonyms.</p><p>Molecular diagnosis — Lineage IV ITS variants, unspecific. The majority of 5S-IGS variants are specific; B Lineage variants largely surpass A Lineage variants in absolute abundance and number of unique sequence variants (Fig. 4; Cardoni &amp; al. 2022). Within Lineage B, European B types (Western B2 variants) outnumber Original B types (exclusively comprising shared types); relatively rare Lineage A variants (probably more common in Pleistocene relict populations, Cardoni &amp; al. 2022, unpublished data) with a preference for Western A type (a lineage shared exclusively with Fagus orientalis) over Shared A type (Fig. 6, 7). Potentially specific SNPs rare but present in CRC, LFY, and Jiang &amp; al.’s (2022) loci P14, P34, P38, P50, F128, F286 and F289 (see F. orientalis); P38 shows a 7 nt-long deletion not detected in any other Fagus sample; P14 characterized by a notably distinct sister genotype of the F. grandifolia genotype: both types differ by six C↔T transitions from the basic type of F. subg. Fagus (Table 3). Distinct isoenzyme Gömöry &amp; Paule (2010) and nuclear SSR profiles (Kurz &amp; al. 2023 marker set at k&gt;2; Fig. 2, 3; see also Budde &amp; al. 2023). Lineage Vb plastomes (species-level plastid type V-Sy; J. Worth &amp; al., work in progress).</p><p>Morphological description — Lamina shape rounded to ovate to elliptic to obovate, usually asymmetric, (20–)40–80(–120) mm long in western populations, (40–)60–120(–145) mm in eastern populations, leaf index [length of leaf/width of leaf) × 100] 150 in western populations, 170 in eastern populations; leaf petiole (2–)5–12(–16) mm long, peaks at values 5, 6 and 10; most frequent base/apex pairs obtuse base and acute apex and acute base and acute apex, in addition, cordate base with acuminate apex and cuneate base with acute apex occur; basal leaf margin entire, wavy (to dentate), apical margin (entire to) wavy to inconspicuously dentate or conspicuously dentate in shade leaves; number of secondary veins (5–)6–10(–12); secondary venation pseudocraspedodromous, semicraspedodromous to craspedodromous in shade leaves, brochidodromous to semicraspedodromous and pseudocraspedodromous in sun leaves; length of stomata (16–)19–29(–32) µm, mean 22.5 µm, subsidiary cells incomplete cyclocytic to cyclocytic or actinocytic, dispersed or in groups; cupule peduncle 4–26(–40) mm, mean value 12 mm, length of cupule 12–26(–29) mm, mean value 20 mm in western populations, (12–)16–28(–32) mm, mean value 22.4 mm in eastern populations, basal cupule appendages reddishbrown, narrow (bud scale homologous) and long woody spines with slender apex, apical appendages long woody spines, often twisted.</p><p>Distribution — Europe (Albania, Austria, Belgium, Bosnia and Herzegovina, Bulgaria, Central European Russia [Kaliningrad Oblast], Croatia, Czech Republic, Denmark, France, Germany, Greece, Hungary, Italy, Liechtenstein, Luxembourg, Moldova, Montenegro, Netherlands, North Macedonia, SE Norway [Vest-/ Ostføld], Poland, Romania, Serbia, Slovakia, Slovenia, N Spain, S Sweden, Switzerland, W Ukraine, S United Kingdom).</p><p>Evolutionary significance — The European beeches represent the sister species of Fagus orientalis (as defined below), the divergence between the sister species has been dated to the late Early Pleistocene by Gömöry &amp; al. (2018), but may have deeper roots (Renner &amp; al. 2016). It is noteworthy that the palaeobotanical record also points to an Early Pleistocene origin of F. sylvatica (Denk &amp; al. 2022). Fagus sylvatica is probably the most recently evolved species within the western Eurasian beech lineage. The currently available molecular data fit with a budding-speciation type process, i.e. the first common ancestor(s) of F. sylvatica evolved from a F. orientalis population that got isolated from the main gene pool and underwent a substantial bottleneck before re-radiating into its modern-day range. Fagus sylvatica plastomes are nearly identical across the entire range of the species stretching from Spain, north and south of the Alps into eastern Europe and the Balkans. Increased genetic variation appears to be restricted to the Apennines (Central Italy; Cardoni &amp; al. 2022) and northwestern Greece and the Rhodopes (Hatziskakis &amp; al. 2009), where it may be para- or sympatric with F. orientalis .</p><p>Remarks on nomenclature — Velenovský (1898, 1902) described a new variety of Fagus sylvatica from the surroundings of the village Kozludža (today Suvorovo, Суворово) in northeastern Bulgaria and from Sliven, eastern Bulgaria, as F. sylvatica var. macrophylla . The name macrophylla had earlier been used by Candolle (1868) and hence cannot be used for this taxon. Based on Velenovský’s concept of F. sylvatica var. macrophylla, Maly in Ascherson &amp; Graebner (1911) established the form F. sylvatica forma moesiaca . Later, Czeczott (1933) erected the new species F. moesiaca (Maly) Czeczott and in the protologue cited a number of herbarium vouchers. We could not find these vouchers in any herbarium collection until 2024, when Dr Maja Graniszewska, curator of the herbarium of the University of Warsaw, was able to locate most of the herbarium sheets in Hanna Czeczott’s archive material at the University of Warsaw, did some cleaning and repairing to them, and provided us with high-resolution scans.</p><p>Among the syntypes, one collection is from the vicinity of Sliven (K. Michoff s.n. WA00000166143, WA00000166142), and a lectotype and isolectotype were chosen from this collection .</p><p>Further remarks — From the surroundings of Tran (Трън), Pernik Province, western Bulgaria, populations with large cupules (30–35 mm) were reported and ascribed to Fagus moesiaca var. borzae Domin (Jordanov &amp; Kuzmanov 1966) . All currently available molecular and morphological data suggest that the eastern European entity F. moesiaca should be included within F. sylvatica (Gömöry &amp; al. 2018). In contrast, POWO (2023) treats F. moesiaca as a synonym of F. ×taurica Popl. ( F. orientalis × F. sylvatica), a name that was originally used only for the Crimean beeches. There is so far little data on the Crimean populations. According to the isoenzyme data of Gömöry &amp; Paule (2010), the Crimean F. ×taurica falls genetically within the overall variation of F. sylvatica as well. More recently, Gömöry &amp; al. (2018) found F. ×taurica to have originated from relatively recent Middle Pleistocene contact between Caucasian beech populations and F. sylvatica s.str. Therefore, F. moesiaca should not be synonymized with F. ×taurica .</p><p>Representative specimens — E. Bourgeau 692 (P [P06857192, P06857207, P06858360]); J.-B. Mougeot s.n. (P [P01035946]); P. Jovet s.n. (P [P00504675]); H. Bouby 493 (P [P06850962]); C. Hering s.n. (P [P06858357]); K. Domin 284c (PRC [PRC 454888 type of Fagus moesiaca (Maly) Domin var. borzae Domin]); J. Madalski 42 (P [P06853549]). — Syntypes of F. moesiaca: P. Černjavski s.n. (WA [WA00000166146, WA00000166147]); H. Czeczott s.n. (WA [WA00000166149]); H. Czeczott s.n. (WA [WA00000166150, WA00000166151]); E. Reimesch (WA [WA00000166152, WA00000166153]). — See Shen (1992) for more representative records.</p><p>Fagus orientalis Lipsky in Trudy Imp. S. - Peterburgsk. Bot. Sada 14: 300. 1898 ≡ Fagus sylvatica subsp. orientalis (Lipsky) Greuter &amp; Burdet in Willdenowia 11: 279. 1981. – Lectotype (designated by Yaltırık 1982: 658): Turkey, Iter orientale, Paphlagonia, Vilayet Kastambuli [Kastamonu province], Kure-Nahas [<a href="https://tb.plazi.org/GgServer/search?materialsCitation.longitude=33.71027&amp;materialsCitation.latitude=41.80598" title="Search Plazi for locations around (long 33.71027/lat 41.80598)">Küre district</a>], in sylvis ad Topschi-Chan, 41°48'21.528''N, 33°42'36.972''E, 9 Sep 1892, P. Sintenis 5113 (LE [LE00011314]; isolectotypes: A [A00033880], G [G00358034-36] [Fig. 11], P [P06812072, P06812074], US [NMNH-00409670 = old no. US 2501956]).</p><p>– Fagus sylvatica var. asiatica A. DC. in Candolle, Prodr. 16(2): 119. 1864, pro parte.</p><p>Molecular diagnosis — Lineage IV ITS variants, may include specific variants (cf. Denk &amp; al. 2002) but better sampled data would be needed. Lineage B variants more abundant than Lineage A variants, the latter more frequent and more diverse than in Fagus sylvatica; Lineage A variants either shared exclusively or highly similar to F. sylvatica variants (dominant Western A type), or representing types ancestral within the western Eurasian lineage (Cardoni &amp; al. 2022; Shared A in Fig. 6, 7); Lineage B variants of the European B lineage subdominant and either related to, or occasionally shared with F. sylvatica (Western B 2 type); Original B lineage much more diverse than in F. sylvatica comprising sequentially distinct types: Shared B1 and related types found across all western Eurasian beeches, Western B 1 types exclusively shared with F. hohenackeriana p.p., other evolved (sequentially distinct) Caucasian types (Hohenackeriana B1a, B1b, B3) rare to very rare but present while absent in F. sylvatica (Fig. 6, 7; Cardoni &amp; al. 2022). Currently no CRC data, and a single LFY accession, differing by a unique T-dominated length-polymorphic sequence motif at pos. 737–764 (supplementary content, file Genotypification.xlsx, sheet LFY LP-patterns). The individual included in Jiang &amp; al. (2022) differs consistently by 26 point mutations from the F. sylvatica samples in the nuclear loci P14 (13), P34 (1), P38 (4), P50 (1), P97 (1), F202 (1) and F289 (5). Distinct isoenzyme (Gömöry &amp; Paule 2010) and nuclear SSR profiles (Kurz &amp; al. 2023, at k =3), the latter involving a west-east gradient (k =2–6, Fig. 3). Lineage V plastomes, subtype yet to be determined.</p><p>Morphological description — Lamina shape elliptic to obovate, usually symmetric, (30–)50–120(–170) mm long, leaf index 196; leaf petiole (2–)3–10(–15) mm long; most frequent base/apex pairs “obtuse base and acute or acuminate apex” and “acute base and acuminate apex”, sun leaves with acute base and apex; leaf margin entire or with blunt triangular or sharp teeth (shade leaves); number of secondary veins (5–)7–12(–15); secondary venation pseudocraspedodromous, semicraspedodromous to craspedodromous; length of stomata (13–)18– 25(–33) µm, mean 22.5 µm, subsidiary cells incomplete cyclocytic to cyclocytic or actinocytic, dispersed or in groups; cupule peduncle (5–)12–14(–75) mm, mean value 25 mm, length of cupule (10–)18–28(–45) mm, mean value 22.5 mm, basal cupule appendages leaf-like, wintergreen (not turning brown in autumn) or summergreen (turning brown during cupule development), spathulate or petiolate, oblong to elliptic in shape, venation dichotomous (in spathulate leaflets) or brochidodromous, area of leaflets decreasing at higher altitudes, apical appendages woody, spine-like.</p><p>Distribution — NE Greece (Thrace), SE Bulgaria, W and N Turkey, S Turkey (Kahramanmaraş, Hatay, Osmanye,? Adana, Mersin).</p><p>Evolutionary significance — Sister species of Fagus sylvatica (see above), geographically and genetically (Kurz &amp; al. 2023, supplement fig. 4) forming the bridge between the eastern species and the beeches of Europe. Morphologically, individuals in lowlands and at mid-elevations are characterized by conspicuous, green, spathulate, leaf-like appendages on the lower parts of the cupule and long cupule peduncles (Fig. 12A, B; Table 4). Similar appendages are also found in the Japanese species F. crenata (F. subg. Fagus) and in the East Asian (China, S Korea) species F. engleriana and F. multinervis (F. subg. Englerianae). From the current still limited data, it can be expected that F. orientalis is genetically richer than its western sister species despite its much smaller overall range and population size. Furthermore, the species appears to be generally closer to the common ancestor of F. sylvatica - orientalis, demonstrated by a higher amount of shared genetic types and stronger morphological affinities to fossil members of its lineage ( F. castaneifolia, F. haidingeri) but also, in contrast to F. sylvatica, to the fossil-species F. gussonii (Denk &amp; al. 2002). Fagus gussonii is a Miocene fossil-species of ambiguous phylogenetic affinities and hypothetical vector for past trans-Atlantic gene flow (Cardoni &amp; al. 2022; Schulze &amp; Grimm 2022). The SSR data clustering results of Kurz &amp; al. 2023 (k ≥3) indicate that the former range of this species may have been much larger, potentially including the disjunct Nur Mountains populations in the Hatay province, southeastern Turkey (Fig. 2). Both the isoenzyme and SSR clustering patterns are possibly affected by (sub)recent gene flow with the Caucasian beech, F. hohenackeriana (in agreement with occasionally found eastern 5S-IGS variants), between their respective ancestors, or incomplete lineage sorting within the ancestor(s) of F. orientalis (- sylvatica) and F. hohenackeriana . Potential hybrid or contact zones include or have included the Nur Mountains and, more importantly, the Parhar Mountains (western extension of the Pontic Mountains) in the hinterland of the Turkish Black Sea coast east of Zonguldak and into southwestern Georgia (Kurz &amp; al. 2023). More in-depth population-level studies are needed to discern to which degree the higher genetic affinity of F. orientalis with its eastern cousin, F. hohenackeriana, than found in its western sister F. sylvatica, is due to (ongoing) gene flow or a generally lower genetic drift (e.g. because of fewer Pleistocene bottleneck events).</p><p>Further remarks — This species is genetically severely understudied in its core range, with most research having focussed on the Bulgarian-Romanian Fagus moesiaca as a putative hybrid or intermediate form between F. sylvatica and F. orientalis . Morphologically, the green, stalked leaflets persisting on the cupule (Table 4) appear to be a most conserved trait, never seen in suggested hybrids outside the known range of the species as shown in Fig. 2. Ongoing research on the Greek side of the eastern Rhodopes has nonetheless revealed mixed stands (individuals lacking or showing green cupule leaflets) of F. sylvatica and F. orientalis that show private 5S-IGS variants in addition to those shared with F. sylvatica or F. orientalis and may be transitional between the sister species (A. Papageorgiou &amp; al., work in progress).</p><p>Representative specimens — BULGARIA: P. Frost-Olsen 1151 (P [P06812193, P06853547]). — TURKEY: J. Bornmüller &amp; F. Bornmüller (E [E00401534]); G. D. Sag 887A (P [P00043490]); P. H. Davis, M. Coode &amp; F. Yaltırık D. 37622 (E [E00401528]); P. H. Davis 18492 (E [E00401511]); B. Balansa 1141 (P [P06812090], US [NMNH-03400246]); J. Manissadjian 369b (P [P06812088 two specimens, one typical F. orientalis, another with transitional cupule appendages, see below]); Det. I. V. Palibin (P [P06812092]); Nur Mountains: P. H. Davis 16398 (E [E00401507]). — Transitional morphologies to Fagus hohenackeriana: Ordu: P. H. Davis &amp; O. Polunin 24935 (E [E00401509]); Amasya: J. Manissadjian 369b (P [P06812041]); Trabzon: A. Stainton 8408 (E [E00401551]); Nur Mountains: Fannie P. A. Shepard 10308853 (US [NMNH-03400252]). — GBIF entries with photographs verify transitional forms to F. hohenackeriana from the provinces of Ordu and Giresun; very rarely transitional forms occur further west (Bolu): C. Aedo 6175 (B [B 10 1167842], MA [MA688421], PRN [PRN2022-024]).</p></div>	https://treatment.plazi.org/id/B10687A8FFD8EB1DFF74FA6BFB8CFAB2	Public Domain	No known copyright restrictions apply. See Agosti, D., Egloff, W., 2009. Taxonomic information exchange and copyright: the Plazi approach. BMC Research Notes 2009, 2:53 for further explanation.		Plazi	Denk, Thomas;Grimm, Guido W.;Cardoni, Simone;Csilléry, Katalin;Schulze, Mirjam Kurz Ernst-Detlef;Simeone, Marco Cosimo;Worth, James R. P.	Denk, Thomas, Grimm, Guido W., Cardoni, Simone, Csilléry, Katalin, Schulze, Mirjam Kurz Ernst-Detlef, Simeone, Marco Cosimo, Worth, James R. P. (2024): A subgeneric classification of Fagus (Fagaceae) and revised taxonomy of western Eurasian beeches. Willdenowia 54: 151-181, DOI: 10.3372/wi.54.54301, URL: https://doi.org/10.3372/wi.54.54301
B10687A8FFC5EB14FCD3FA68FD60F9B2.text	B10687A8FFC5EB14FCD3FA68FD60F9B2.taxon	http://purl.org/dc/dcmitype/Text	http://rs.tdwg.org/ontology/voc/SPMInfoItems#GeneralDescription	text/html	en	Fagus hohenackeriana Palib.	<div><p>Fagus hohenackeriana Palib. in Bull. Herb. Boissier,</p><p>sér. 2, 8: 378. 1908, as “ hohenackerana ”. – Lectotype (designated here): Azerbaijan, Lesser Caucasus,</p><p>1838–1833, R. F. Hohenacker s.n. (G [G00358037_a]</p><p>[Fig. 13]; isolectotypes: E [E00326761], G [G00358037,</p><p>G00358037_b], US [NMNH-00409517-000001]).</p><p>– Fagus sylvatica var. macrophylla Hohen. in Bull. Soc. Imp. Naturalistes Moscou 1838: 259. 1838, pro parte, nom. nud.</p><p>– Fagus sylvatica var. macrophylla Hohen. ex A. DC. in Candolle, Prodr. 16(2): 118. 1864, pro parte.</p><p>– Fagus sylvatica subsp. hohenackeriana (Palib.) C. F. Shen, Monogr. Fagus: 60. 1992, pro parte, combination not effectively published (Art. 30.9).</p><p>Molecular diagnosis — ITS variants belonging to Lineage IV, preliminary data indicate Lineage IV ITS variants not shared with Fagus sylvatica and F. orientalis . Most diverse and heterogenous 5S-IGS pool of all species analysed so far (Fig. 5), A Lineage variants can be more abundant than B Lineage variants (Lesser Caucasus and eastern Georgian sample) or vice versa (Greater Caucasus sample, Fig. 7); no European B variants. A Lineage variants (co-)dominated either by private to this species European A types (Hohenackeriana A1, sister lineage of Western A type) and/or the unspecific variants of the Shared A type, additional rare A-lineage types shared with the eastern sibling F. caspica; B Lineage variants sequentially and type-wise diverse (Fig. 6), characteristically including shared (Shared B, Western B) and (near-) exclusive (Hohenackeriana B1a, B1b, B2 and B3) types with shifting abundances between samples, a genotypic feature not found in any of the other species. Distinct isoenzyme (Gömöry &amp; Paule 2010) and nuclear SSR profiles (Kurz &amp; al. 2023), separating F. hohenackeriana and F. caspica from F. sylvatica - orientalis at k =2 and k =3. Fagus hohenackeriana and F. caspica differentiated at higher k and in the densely sampled nuclear SSR data of Sękiewicz &amp; al. (2022; mapped in Fig. 3). [No other nuclear data available.] Lineage V plastomes, subtype not yet determined.</p><p>Morphological description — Lamina shape elliptic to obovate, usually symmetric, (60–)80–140(–200) mm, leaf index 187; leaf petiole (1–)2–9(–13) mm long; most frequent base/apex pairs “oblong very-base and blunt acute or blunt acuminate apex” and “slightly cordate or nearly oblong very-base and attenuate apex” chiefly on vegetative twigs, “acute base and apex” on fruiting twigs and sun leaves; leaf margin entire or with blunt triangular teeth (shade leaves); number of secondary veins (6–)7–12(–16); secondary venation pseudocraspedodromous, semicraspedodromous to craspedodromous in shade leaves; length of stomata (16–)20–26(–30) µm, mean 23.5 µm, subsidiary cells incomplete cyclocytic to cyclocytic or actinocytic, dispersed or in groups; cupule peduncle 5–38 mm, mean value 19 mm, length of cupule (6–)15–25(–38) mm, basal cupule appendages (1) parallelodromous, membranous brownish scales similar to bud scales, usually densely spaced (Fig. 12C), (2) small sessile leaflets initially green but soon turning brown, spathulate to lanceolate, with dichotomous venation or (3) woody spine-like appendages similar to apical ones, apical appendages woody, spine-like.</p><p>Distribution — NE Turkey, Lesser Caucasus (Georgia, Armenia, Azerbaijan), Transcaucasus (Georgia, Azerbaijan), North Caucasus (Russia).</p><p>Evolutionary significance — The isoenzyme data of Gömöry &amp; Paule (2010) and the SSR data clustering of Kurz &amp; al. (2023) indicate that the split between Fagus hohenackeriana (+ F. caspica) and F. orientalis predates the split between the latter and its European sister, F. sylvatica . This is corroborated by the 5S-IGS lineages and frequent or (very) rare types shared exclusively with either F. orientalis (sister types Hohenackeriana B1b and Western B1, both sequentially distinct derivates of the commonly shared Original B types), F. sylvatica (Hohenackeriana A1, sister type of Western A) or both (Western A). The available high-resolution genetic data also indicate that F. hohenackeriana has been less isolated from its western cousins than the easternmost F. caspica and differs from the latter by an increased intra-species genetic diversity. Sękiewicz &amp; al. (2022) found a genetic cline between the southern, western and central populations of F. hohenackeriana (eastern Pontic Mountains, Lesser Caucasus, western and central High Caucasus in Georgia) and the eastern High Caucasus populations in northeastern Azerbaijan. This finding correlates with the differential composition of the 5S-IGS pools of the three samples included here (Fig. 6) which sets the sample from the Greater Caucasus (Racha) apart from those of the Lesser Caucasus (Borjomi + Bakuriani) and eastern Georgia (Lagodekhi): in the Racha population, hohenackeriana -specific 5S-IGS B Lineage variants co-occur with variants of a lineage also found in the western F. orientalis but very rare in the other two populations of F. hohenackeriana . In contrast, the latter share some types with their eastern sibling, F. caspica, types not found in F. orientalis or the Racha population. At this point, the genetics would fit with two evolutionary hypotheses about the origin of F. hohenackeriana . It may represent the eastern sister species of F. sylvatica + F. orientalis, sharing a common ancestor with the precursor of F. orientalis (+ later evolved F. sylvatica), spreading across Asia Minor and the Caucasus before Anatolia and the entire eastern Mediterranean region dried out and became more continental. Or, it is the sister species of F. caspica and both species evolved from the Pontic-Hyrcanian populations of the fossil-species F. haidingeri in contrast to F. sylvatica - orientalis that evolved from the Euro-Mediterranean populations of F. haidingeri, with the fossil-species F. gussonii being the second donor. Under both scenarios, the notably high 5S-IGS heterogeneity of F. hohenackeriana could be explained by genetic legacy from further species/populations that thrived north/northeast of the modern F. hohenackeriana before the Pleistocene (north of the Paratethys and its remnant, the Caspian Sea) as well as ongoing speciation processes in the Caucasus and adjacent areas characterized by a strong topographic relief and geographic vicinity of strongly differing niches (cf. Denk &amp; al. 2001, for the ecology and biocenoses of beech forests in Georgia).</p><p>Remarks on nomenclature — There has been some nomenclatural confusion surrounding the Caucasian-Hyrcanian beeches. Based on the initial work by Hohenacker (1833, 1838) and the taxonomic treatments by Candolle (1868) and Palibin (1908), Shen (1992) correctly considered Fagus hohenackeriana Palib. ( F. sylvatica subsp. hohenackeriana sensu Shen; Caucasus-Hyrcanian region) different from F. sylvatica subsp. orientalis . Since no types had been cited in previous works, but both Candolle and Palibin had referred to material collected by Hohenacker, Shen chose a lectotype for F. hohenackeriana from herbarium G collected from “Azerbaijan-Talysh” Mountains (Shen 1992: p. 166). He further listed isolectotypes from G, LE, and US. In doing so, Shen (1992) confused different collections of F. hohenackeriana, namely material collected earlier from the Lesser Caucasus s.l. (Azerbaijan part of Karabakh Mountains; Hohenacker 1833; including the isotypes selected by Shen) and later from the Talysh Mountains of Azerbaijan (Hohenacker 1838). These collections represent geographically and genetically distinct populations and hence they cannot be lectotypes of a single species (cf. Sękiewicz &amp; al. 2022, fig. 3 AZ_01, Lesser Caucasus, versus HZ_01, HZ_02, Talysh).</p><p>Hohenacker, a Swiss missionary based in Şuşa (German: Schuscha) in Nagorno-Karabach, started collecting plant specimens for the Esslinger Reiseverein (“Esslinger Travel Society”) in the early 1830s (Wörz 2007). These plant specimens were sent to Germany and distributed among the members of the travel society. A first parcel of dried plant specimens, collected by Hohenacker between 1830 and 1833, contained plants from the environs of Şuşa and the mountains of Nagorno-Karabach (see Hohenacker 1833; Hochstetter &amp; Steudel 1834). These plants were accompanied by labels with the locality information “Caucasus” (isolectotypes of Fagus hohenackeriana at herbarium Genève, G00358037; Edinburgh, E00326761; Smithsonian, US 00409517).</p><p>During a subsequent collecting trip in the summer and autumn 1834, Hohenacker collected plants from the surroundings of Lankaran and explored the montane regions of Zuvand (“district Suwant”) and Dirig/Dırığ (“district Drych”). He collected Fagus from the environs of the villages Cayrud (“Tschaioru”) and Veri (“Weri”; Hohenacker 1838). In October 1835, Hohenacker collected Fagus in southern Talysh, close to the border of Iran. In the publication arising from his collection trip (Hohenacker 1838), he reported F. sylvatica var. macrophylla occurring “in sylvis montium Talysch prope Lenkoran, Drych, Suwant, Astara” (p. 259). The material collected during this expedition does not have “Caucasus” on the labels, but, for example “in forests in the surroundings of Lenkoran” (e.g. Hohenacker 2229 in herbarium Paris, barcode P06812042).</p><p>Hence, we here clarify the origin of the lectotype of Fagus hohenackeriana and refer Fagus populations occurring from northeastern Turkey to the Greater and Lesser Caucasus to this species. In contrast, we refer the populations originating from the Talysh Mountains and the Hyrcanian region as F. caspica (see below).</p><p>Further remarks — So far, only the spacers of the nuclear-encoded ribosomal DNA have been sequenced (Denk &amp; al. 2002, 2005; this study). The Caucasian populations are not covered in Jiang &amp; al. (2022) nor in the upcoming study of Worth and co-workers. Armenian and Georgian populations have been included in the study of Paffetti &amp; al. (2007) but their data had not the necessary quality or resolution to identify novel plastid haplotypes within the western Eurasian plastid lineage (Lineage V). Based on our experience with other Caucasian trees ( Acer, Quercus), we expect that in-depth nuclear-genetic analyses will reveal further diagnostic traits. Screening of the nuclear loci of Jiang &amp; al. (2022) comprising alleles reflecting the trans-Atlantic link (introgression: genes P14, P21, P54, and F289; cf. Cardoni &amp; al. 2022) may help to decide between the two hypotheses outlined above. By extending the sample of Sękiewicz &amp; al. (2022) to adjacent areas (Crimean, northeastern Turkish and additional Armenian and Iranian populations), it may be possible to further explore the nature of the genetic gradient found in Fagus hohenackeriana and, potentially, reveal ongoing speciation processes between the western (+ Pontic Mountains) and eastern Caucasus.</p><p>Representative specimens — TURKEY: P. H. Davis &amp; I. Hedge D32347 (E [E00401564]); M. Tong 504 (E [E00401561]); P. H. Davis &amp; J. Dodds 21380 (E [E00401562]); P. Sintenis 1609 (P [P06812039]); ENET 33 (E [E00318857]); [?] 828 (G [G00754880]). — LESSER CAUCASUS: T. Denk 977154 (US [NMNH-03400173]); J. C. Solomon 20783 (US [NMNH-03470668]); T. Denk 977229 (U [U0251466]). — TRANSCAUCASUS: T. Denk 896127 (BR [BR0000030519022]); V. Vašák s.n. (BR [BR0000030518865]); T. Denk 977011 (BR [BR0000030520585]); E. E. Gogina 47 (BR [BR0000030519084]); E. E. Gogina s.n. (E [E00401536]); S. Kuthatheladze &amp; I. Mandenova (E [E00401545]); J. Reveal 8715 (P [P06851162]); T. Denk 896179 (P [P06812068]); T. Denk 8965 (P [P06812069]); T. Denk 977057 (P [P06851975]); T. Denk 977 (P [P06851976]); T. Denk 977222 (P [P06851978]); E. Gabrielian 12766 (E [E00401548]); V. Manakyan s.n. (E [E00401555]); P. Smirnow 312 (MW [MW0660524]); M. Barkworth &amp; al. s.n. (NY [NY03476707]); L. N. Cilikina s.n. (MW [MW0660529]); L. N. Cilikina s.n. (MW [MW0660537]); T. Alexeenko 84b (DR [DR061665]). — NORTH CAUCASUS: B. Marcowicz s.n. (P [PI031307]); B. Marcowicz s.n. (E [E00401556]); B. Marcowicz s.n. (E [E00401557]).</p></div>	https://treatment.plazi.org/id/B10687A8FFC5EB14FCD3FA68FD60F9B2	Public Domain	No known copyright restrictions apply. See Agosti, D., Egloff, W., 2009. Taxonomic information exchange and copyright: the Plazi approach. BMC Research Notes 2009, 2:53 for further explanation.		Plazi	Denk, Thomas;Grimm, Guido W.;Cardoni, Simone;Csilléry, Katalin;Schulze, Mirjam Kurz Ernst-Detlef;Simeone, Marco Cosimo;Worth, James R. P.	Denk, Thomas, Grimm, Guido W., Cardoni, Simone, Csilléry, Katalin, Schulze, Mirjam Kurz Ernst-Detlef, Simeone, Marco Cosimo, Worth, James R. P. (2024): A subgeneric classification of Fagus (Fagaceae) and revised taxonomy of western Eurasian beeches. Willdenowia 54: 151-181, DOI: 10.3372/wi.54.54301, URL: https://doi.org/10.3372/wi.54.54301
B10687A8FFCCEB15FF74F968FD4DF932.text	B10687A8FFCCEB15FF74F968FD4DF932.taxon	http://purl.org/dc/dcmitype/Text	http://rs.tdwg.org/ontology/voc/SPMInfoItems#GeneralDescription	text/html	en	Fagus caspica Denk & Grimm & Cardoni & Csilléry & Schulze & Simeone & Worth 2024	<div><p>Fagus caspica Denk &amp; G. W. Grimm, sp. nov.</p><p>Holotype: Iran, Gilan province, Deylaman to <a href="https://tb.plazi.org/GgServer/search?materialsCitation.longitude=49.91028&amp;materialsCitation.latitude=37.04139" title="Search Plazi for locations around (long 49.91028/lat 37.04139)">Siahkal</a>, 37°02'29''N, 49°54'37''E, 1350 m a.s.l., 7 Jun 2011, J. Noroozi 2349 (W [W20180003068 Fig. 14 https://www.jacq.org/detail.php?ID=1383327]; isotype: W [W20180003067 https://www.jacq.org/detail.php?ID=1383326]).</p><p>– Fagus sylvatica var. macrophylla Hohen. in Bull. Soc. Imp. Naturalistes Moscou 1838: 259. 1838, pro parte, nom. nud.</p><p>–</p><p>–</p><p>– Fagus sylvatica var. macrophylla Hohen. ex A. DC. in Candolle, Prodr. 16(2): 118. 1864, pro parte.</p><p>Fagus hohenackeriana Palib. in Bull. Herb. Boissier, sér. 2, 8: 378. 1908, pro parte.</p><p>Fagus sylvatica subsp. hohenackeriana (Palib.) C. F. Shen, Monogr. Fagus: 60. 1992, pro parte, combination not effectively published (Art. 30.9).</p><p>Molecular diagnosis — ITS variants belonging to Lineage IV, possibly specific (based on limited individual-level and old sequence data). 5S-IGS variants predominately specific, typically not shared with any other western Eurasian species but least evolved, i.e. relatively close to the putative ancestral sequence variants; B lineage variants slightly more abundant or nearly as abundant as A lineage variants, and equally diverse (Fig. 5; Cardoni &amp; al. 2022), no European A and European B variants; A Lineage variants predominately of the Shared A type, types shared with Fagus hohenackeriana p.p. rare (Eastern A) to very rare (Hohenackeriana A2); B Lineage variants dominated by the (originally specific?), derived Caspica B 1 type, and the underived, cross-species shared Ancestral B1/Shared B 1 types (Fig. 6, 7), the high abundance of the latter is a genotypic characteristic of F. caspica and to a lesser degree, F. orientalis; no Western B1/Hohenackeriana B1b types. Very distinct isoenzyme (Gömöry &amp; Paule 2010) and homogenous nuclear SSR profiles (Kurz &amp; al. 2023), separating F. caspica from its putative sister species F. hohenackeriana at k =4 (see also Sękiewicz &amp; al. 2022, k =2 vs k =3; mapped in Fig. 3). Lineage Va plastomes (species-level plastid type V-EO). CRC distinct from Fagus sylvatica, differing in at least five alignment patterns, three species-consistent SNPs (pos. 800, 85, 1674 in reference alignment) and two to three other (cf. supplementary content, file Genotypification.xlsx, sheet CRC LP-patterns); A-dominated motif at position 830–859 in CRC near-exclusively composed of A (terminating on G, GG, TG in all other species). No LFY or low-copy nuclear loci data so far. Lineage Va plastomes, differing by 564–642 SNPs from the plastomes of their westernmost cousin, F. sylvatica (Lineage Vb plastomes), about the same level of difference as found in East Asian individuals carrying the same plastome lineage (Japanese Lineage II median: 637 SNPs; East Asian Lineage IV median: 462 SNPs) and about half of the maximum difference recorded so far (1198 SNPs between Lineage I plastome of F. grandifolia from Michigan and a Lineage IV F. crenata plastome; supplementary content, file Genotypification.xlsx, sheet PlstmDissim).</p><p>Morphological description — Lamina shape ovate to elliptic, usually asymmetric, (60–)80–120(–140) mm long, leaf index 188; leaf petiole (2–) 7–12 mm long; most frequent base/apex pairs “cordate asymmetric or symmetric base and attenuate apex”; basal leaf margin entire to wavy, sometimes with blunt teeth, apical margin commonly with prominent teeth; teeth (1) with long, convex, concave or straight basal side and short, steep apical side, or (2) small, pronounced teeth with slightly convex margin between two consecutive teeth; number of secondary veins (7–)8–14(–16); secondary venation brochidodromous to pseudocraspedodromous basally, semicraspedodromous to craspedodromous apically; length of stomata (16–)20– 26(–30) µm, mean 23 µm, subsidiary cells incomplete cyclocytic to actinocytic, with transitions to anomocytic; cupule peduncle (5–)9–25(–40) mm, mean value 17 mm, length of cupule 5–29 mm, mean value 17 mm, basal cupule appendages parallelodromous, membranous, reddish-brown, narrow, similar to bud scales or thread-like (Fig. 12:D), or narrow spathulate brownish leaflets with obtuse, forked or acute apex, apical appendages woody spine-like, sometimes forming clusters.</p><p>Distribution — SE Azerbaijan (Talysh), N Iran.</p><p>Evolutionary significance — Genetically, the Iranian populations are the leftover of the initial speciation processes within the precursor(s) of all western Eurasian beeches, as reflected by their many private 5S-IGS variants. The difference between their plastomes and those of Fagus sylvatica is double to triple as high as observed between East Asian species carrying Lineage IV plastomes, which includes the plastomes of all Chinese and Taiwanese beeches and the southeastern populations of the Japanese beeches (cf. Worth &amp; al. 2021). Morphologically, the numerous, densely spaced secondary veins, the usually distinctly serrate leaf margin, and the elongate leaf apex resemble fossils from Middle Miocene strata of Austria and Russia (Zetter 1984; Yakubovskaya 1975). Denk (1999a), furthermore, pointed out leaf morphological similarities with North American populations of F. grandifolia, a likely symplesiomorphic pattern.</p><p>Etymology — The species name refers to the distribution of the species along the southern shores of the Caspian Sea in Azerbaijan and northern Iran.</p><p>Representative specimens — R. Hohenacker 2229 (P [P06812042]); T. Alexeenko (MW [MW0660538]); A. Ghorbani &amp; A. Pirani 1196 (TMRC [TMRC0001196]); K. H. Rechinger 20006 (US [NMNH-03400239]); D. Lyskov &amp; T. Krutenko (MW [MW0754378]); A. A. von Bunge (G [G00754877]); J. Lamond 2966 (E [E00401560]); J. Lamond 5136 (E [E00401553]); P. M. R. Aucher-Eloy 5325 (P [P06812078]); D. Walton 242 (E [E00400275]); D. Walton 243 (E [E00401554]); H. de Hell (P [P06812075]); I. V. Palibin (K [K00832763]).</p></div>	https://treatment.plazi.org/id/B10687A8FFCCEB15FF74F968FD4DF932	Public Domain	No known copyright restrictions apply. See Agosti, D., Egloff, W., 2009. Taxonomic information exchange and copyright: the Plazi approach. BMC Research Notes 2009, 2:53 for further explanation.		Plazi	Denk, Thomas;Grimm, Guido W.;Cardoni, Simone;Csilléry, Katalin;Schulze, Mirjam Kurz Ernst-Detlef;Simeone, Marco Cosimo;Worth, James R. P.	Denk, Thomas, Grimm, Guido W., Cardoni, Simone, Csilléry, Katalin, Schulze, Mirjam Kurz Ernst-Detlef, Simeone, Marco Cosimo, Worth, James R. P. (2024): A subgeneric classification of Fagus (Fagaceae) and revised taxonomy of western Eurasian beeches. Willdenowia 54: 151-181, DOI: 10.3372/wi.54.54301, URL: https://doi.org/10.3372/wi.54.54301
