Crimean beech

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Crimean beech
Systematics
Rosids
Eurosiden I
Order : Beech-like (Fagales)
Family : Beech family (Fagaceae)
Genre : Beech ( Fagus )
Type : Crimean beech
Scientific name
Fagus taurica
Popl.

The Crimean beech is a family of plants of unclear taxonomic classification from the beech genus ( Fagus ), which is between the common beech ( Fagus sylvatica ) and the oriental beech ( Fagus orientalis ) in terms of its characteristics . It was described as Fagus taurica in the species class , but is often considered a hybrid species ( Nothospecies Fagus × taurica ). It is named after Tauris , the (presumed) ancient name of Crimea. It is the only naturally occurring beech taxon on the Crimean peninsula in the north of the Black Sea.

description

Vegetative characteristics

The Crimean beech resembles the common red beech and the oriental beech and is not different from them in most of the morphological characteristics. It is variable in the characteristics that are used to differentiate, mostly in the characteristic expression between these and cannot be clearly assigned to either of the two. The leaves are, with great variability, on average larger than those of Fagus sylvatica , the number of lateral nerves is (5-) 8 to 10 (-12) ( Fagus orientalis : 8–13, Fagus sylvatica s. Str .: mostly 5-9).

Generative characteristics

The flowers sheath ( Perigon ) of the male flowers is as Fagus orientalis rather bell-shaped with shorter lobes. The shape of the scales of the fruit cup (cupula) is very variable, whereby tree specimens with narrow, pointed and wide, lanceolate scales occur next to each other on the cupula.

Ecology and diffusion

The Crimean beech only grows in the mountains in the south of the Crimea, at an altitude of 500 to 1300 meters, mostly on north or north-west exposed slopes, it reaches a height of 25 meters and has trunk diameters of over 40 centimeters. At lower altitudes, it is limited to damp, shady valleys. In the higher, subalpine altitudes above 1200 meters it forms crooked, bush forest-like stands up to a maximum of 12 meters in height. The Crimean beech is the dominant forest tree species in Crimea at the corresponding altitude.

The beech forests of the Crimea are in vegetation an association Dentario quinquefoliae-Fagion , named after the character species Dentaria quinquefolia (according to another taxonomic view: Cardamine quinquefolia ). In the EUNIS classification, the beech forests of the Crimea form type G1.6G - Crimean Fagus forests.

Systematics

The systematic position of the Crimean beech is still unclear and controversial. While many of the older florists and botanists were of the opinion that common red beech and oriental beech would occur side by side in the Crimea, so that the emergence of numerous primary hybrids could be expected, the Russian botanist Henrietta Poplavskaja then pointed out that the variability of the Trees are too small for such a hybrid swarm. After more detailed morphological investigations, she described the Crimean beech in 1928 as Fagus taurica Popl., Pointing to the position intermediate between the two species. In his 1999 revision, Thomas Denk came to the conclusion that the characteristics of the trees were more similar to the oriental beeches of the Caucasus, but left the question open because of the lack of access to material. Earlier editors such as Hanna Czeczott had assigned them to Fagus orientalis . The problem was exacerbated by the fact that in 1933 Czeczott described beeches from the southern Balkan peninsula , which also show intermediate characteristics, as a separate species Fagus moesiaca . In addition, the botanists were already divided on the status of the oriental beech, which numerous botanists perceived as a subspecies of the red beech instead of a species of its own. Since Fagus moesiaca is also vague in the definition of characteristics, some botanists began to equate both clans and also to refer to the intermediate beeches of the Balkans as Fagus taurica , the concept of a synonymy is also followed in the Kew Plant List.

More recent phylogenomic results, in which the relationship is determined by comparing homologous DNA sequences, then confirmed the hybridogenic origin of the Crimean beech, from the common red beech and the oriental beech of the Caucasus and the Colchis , during the Saale Ice Age or, more likely , in 2018 , the Eem warm period . The Crimean beech is now separated from the beech deposits of the Balkans and those of the Caucasus by a distribution gap, but these could have come into contact here under different climatic conditions. In the same study it was shown that the beeches of the Balkans described as Fagus moesiaca are probably not of hybridogenic origin, but rather tribes of origin that were primarily formed during the emergence of the common European beech Fagus sylvatica during immigration from the east. Very similar results had already been achieved in 2007 and 2010 in investigations based on allozymes .

If one follows this view, the Crimean beech is a hybridogenic plant family. So it would not be a primary hybrid that would emerge again and again from the recent crossing of the two parent species. Whether it is a (small) species, a subspecies, a variety or an ecotype depends on the taxonomic conception of Fagus sylvatica s. l. dependent. This is still treated differently in different plants, so that the status is currently unclear.

Individual evidence

  1. ^ A b H. Poplawska (1928): The beech in the Crimea and its variability. In: Austrian Botanical Journal 77 (1): 23-42.
  2. ↑ Wolfgang Willner, Borja Jiménez ‐ Alfaro, Emiliano Agrillo, Idoia Biurrun, Juan Antonio Campos, Andraž Čarni, Laura Casella, János Csiky, Renata Ćušterevska (2017): Classification of European beech forests: a Gordian Knot? In: Applied Vegetation Science 20 (3): 494-512. doi: 10.1111 / avsc.12299
  3. ^ Crimean Fagus forests. EUNIS fact sheet - European Environment Agency .
  4. ^ A b Thomas Denk (1999): The taxonomy of Fagus in western Eurasia. 2: Fagus sylvatica subsp. sylvatica. In: Feddes Repertorium 110 (5/6): 381-412.
  5. ^ Hanna Czeczott (1932): Distribution of Fagus orientalis Lipsky. In: Publications of the Geobotanical Institute Rübel in Zurich 8: 362-387.
  6. ↑ Fagus × taurica Popl .. The Plant List, a working list for all plant species , Version 2, as of 2013
  7. ↑ Dušan Gömöry, Ladislav Paule, Vladimír Mačejovský (2018): Phylogeny of beech in western Eurasia as inferred by approximate Bayesian computation. In: Acta Societatis Botanicorum Poloniae 87 (2): 3582. doi: 10.5586 / asbp.3582 .
  8. ↑ Dušan Gömöry, Ladislav Paule, Jozef Vyšny (2007): Patterns of allozyme variation in western Eurasian Fagus. In: Botanical Journal of the Linnean Society 154 (2): 165-174. doi: 10.1111 / j.1095-8339.2007.00666.x (open access)
  9. ↑ Dušan Gömöry, Ladislav Paule (2010): Reticulate evolution patterns in western-Eurasian beeches. In: Botanica Helvetica 120 (1): 63-74.

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