The Karpatian (Late Early Miocene) Flora of the Mecsek Area
Total Page:16
File Type:pdf, Size:1020Kb
Acta Palaeobotanica 60(1), 51–122, 2020 e-ISSN 2082-0259 https://doi.org/10.35535/acpa-2020-0003 ISSN 0001-6594 The Karpatian (late early Miocene) flora of the Mecsek area LILLA HABLY Botanical Department, Hungarian Natural History Museum, H-1431 Budapest, P.O. box 137, Hungary; e-mail: [email protected] Received 9 September 2019; accepted for publication 28 January 2020 In remembrance of the beautiful summers spent collecting with my family in the Mecsek Mountains ABSTRACT. A rich macroflora has been collected from Karpatian (late early Miocene) layers of the Mecsek Mts during recent decades. The bulk of the fossil assemblage consists of leaves and also fruits of angiosperms. Among the more than a hundred taxa, several endemic species were described: Leguminocarpum mecsekense Andreánszky, Ailanthus mecsekensis Hably, Nyssa gyoergyi sp. nov., Nyssa gergoei sp. nov., Nyssa sp. 1, Clematis csabae sp. nov., Gordonia sp. and Carpolithes gergoei Hably et Erdei sp. nov. Many taxa were last recorded in the Carpathian Basin, e.g. Cedrelospermum, Ziziphus. Other taxa appeared in this flora, e.g. Quercus kubinyii, Podocarpium podocarpum, Liquidambar europaea and Populus populina, and later became dominant in the middle Miocene (Sarmatian) floras or even in the late Miocene (Pannonian) floras. Four main vegetation types were determined. The most significant types are subxerophytic vegetation showing high diversity, swamp veg- etation, riparian vegetation, and a vegetation type growing in habitats with higher rainfall. Thermophilous flora elements are dominant in the assemblage, although “arctotertiary” species also appear. The floristic character of the flora supports the results of an earlier quantitative climate analysis of the Magyaregregy flora, accord- ing to which mean annual temperature was 15.6–16.6°C and coldest-month and warmest-month temperatures were 5–6.2°C and 24.7–27.9°C, respectively. Generally the assemblage presented in this paper extends those climatological findings to the late early Miocene. KEYWORDS: macroflora, late early Miocene, Karpatian, Mecsek Mts, Hungary INTRODUCTION Geological research in the Mecsek Mts dates (2010, 2011), Józsa and Szakmány (2011), back many decades. The extreme variability of Sebe et al. (2015a,b), Miklós (2018) and Kovács its geology, high diversity of rock formations, et al. (2018). and the potential scientific value of strata Palaeontological research on the Mecsek spanning geological ages have attracted many Mts has been very intensive, reflected in work geologists and palaeontologists to this area. published by Strausz (1950). Foraminifers It is beyond the scope of this work to cite and nannoplankton were studied by Korecz- all the relevant literature even in the field of Laky (1968), and Báldi-Beke (1963) respec- Cenozoic research. Only some are mentioned tively. Palynological studies were carried out here. Publications on the Cenozoic geology of by Nagy (1969). The first floristic study of the the Mecsek Mts include Strausz (1926, 1926– Miocene flora of the Mecsek Mts was published 28), Hámor (1964), Nagymarosy (1980, 1985), by Staub (1882), who collected relatively few Chikán (1991), Szakmány and Józsa (1994), specimens from several sites and mentioned Magyar et al. (1999), Sebe (2009), Józsa et. al. the localities Rákpatak-völgy near Ó-Falu, (2009), Barabás (2010, 2011), Konrád and Sebe Nádasd, Hidas, Magyar-Hidas, Német-Hidas, © 2020 W. Szafer Institute of Botany, Polish Academy of Sciences This is an Open Access article, distributed under the terms of the Creative Commons Attribution licence (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted re-use, distribution, and reproduction in any medium, provided the original work is properly cited 52 L. Hably / Acta Palaeobotanica 60(1), 51–122, 2020 Váralja, Puszta-Szobák, Komlóvölgy, Aba- be identified. To ground future research, the liget, Tekeres and Rákos, which all, except unidentified specimens are also discussed and for Váralja, represent marl with fish scales. figured. The extremely diverse assemblage is At Váralja, deposits preserving the plant used to reconstruct the flora and vegetation, remains were described as quartz-andesitic and to make a climatic analysis. tuff. The figures, which are drawings of the fossil specimens, help in recognition of some genera and species: Pinus, Daphnogene (given GEOLOGICAL SETTINGS as Cinnamomum by Staub), Ziziphus paradi siaca, Zelkova zelkovifolia (given as Planera The area of Mecsek is situated in the SW Ungeri by Staub), Ailanthus confucii, Myrica Pannonian Basin on the Tisza-Dacia megaunit, and Leguminosae gen. et sp. (given as Cas a tectonic block south of the Mid-Hungarian sia by Staub). The occurrence of these genera Shear Zone. The Neogene stratigraphy of and species in the small fossil assemblage sug- the eastern Mecsek area was summarized by gests that these taxa were frequent members Hámor (1970), whereas the western part was of the Miocene flora of the Mecsek Mts. Unfor- studied by Chikán (1991) and Barabás (2010). tunately, many of the drawings could not be Widespread Lower Miocene fluvial clastics, identified, and the often-invalid old names do including conglomerates to variegated clays not help in their taxonomic assignment. (Szászvár Formation), are overlain by the Later, Andreánszky (1955) and Pálfalvy Budafa Formation, traditionally regarded as (1953, 1961, 1964, 1967) published data for the of Karpatian (late Burdigalian) age (Gyalog, Miocene Mecsek flora, but they often merely 1996; Gyalog and Budai, 2004; Budai et al., gave lists of flora without providing figures 2015) and consisting of three members: the and descriptions. That work did not constitute Komló Claymarl Member, Pécsvárad Lime- a survey of the Mecsek flora. Over a period of stone Member, and the overlying Budafa more than two decades, I and my colleagues Sandstone Member. The succession is over- have made collections, studied a number of lain by the Badenian (Langhian), with normal taxa, and revised many of them (Hably, 1992b, marine Leitha limestones (Lajta Limestone 2001, 2002; Hably and Thiébaut, 2002). Col- Formation, Pécsszabolcs and Rákos Members) lections made by Krisztina Sebe have yielded in the littoral zone, and offshore sands and data essential to our knowledge of the Mio- silts (Tekeres and Szilágy Formations) in the cene flora of the Mecsek Mts. There are many basins, locally with coal-bearing swamp depos- sampling sites in the Mecsek Mts. Most of the its (Hidas Formation) along the shores. fossil specimens (~90%) were collected in the Most of the fossil plant remains were fos- surroundings of Magyaregregy, mostly from silized in the Komló Claymarl Member (“fish- the so-called fish-scale marl there, but some scale-bearing clay marl”). It is composed of dark also from volcanic deposits. Fossils have been grey, greenish grey, massive or laminated silty preserved in the so-called fish-scale marl in clay marl, calcareous silt and fine sands, with Magyaregregy, Vágyom-völgy; Kisbattyán; numerous fish scales and bones, and sometimes Magyaregregy, Leánykői-árok; Magyaregregy, with tuff interbeds. K/Ar dating measurements Kisréti-árok; Magyaregregy, Farkasordító- from tuff interbeds within the Komló Claymarl árok; Abaliget, Kiskő-hegy; and also Abaliget, showed an age of 16.82 ± 0.65 Ma, i.e. Karpatian Nyáras-völgy. Fossils originated from rhyolitic (late Burdigalian) (Sebe et al., 2019). tuff in Magyaregregy, Almás-patak; Kisbesz- The absence of marine forms in the Péc- terce and Hetvehely, Kán. The late Miocene svárad Limestone and in most of the Komló (Pannonian) flora of Mecsek is not discussed Claymarl indicates a lack of connection to here; details can be found in Hably (2013), normal-salinity seas; thus these rocks are Hably and Sebe (2016) and Hably et al. (2019). lacustrine deposits (Sebe et al., 2019). The The main part of the monograph deals with lake sediments and the fauna suggest that systematics, describing and discussing more instead of a system of smaller lakes, a con- than 100 taxa. The Mecsek flora is extremely tiguous waterbody called Lake Mecsek existed diverse. Beside the well-known common spe- in the area. Karpatian to early Badenian cies, many rare taxa occur in the assemblage, age of the lake is indicated by K/Ar age and and a high number of specimens could not biostratigraphic dating of the overlying marine L. Hably / Acta Palaeobotanica 60(1), 51–122, 2020 53 deposits described above (Sebe et al., 2019). D e s c r i p t i o n. Stem fragment with nodes, The Pécsvárad and Komló Members are both 6.0 cm long, 0.5 cm wide. The stem jointed at interpreted as lake deposits and differ very the nodes. Four strong ridges on stem surface. much from the Budafa Sandstone Member; D i s c u s s i o n. Heer (1855) described numer- therefore, Sebe et al. (2019) united the two ous specimens from the Tertiary flora of Swit- members as a separate formation, the Feked zerland. Andreánszky (1959) published the Formation. Consequently, the fish-scale-bear- species from the Sarmatian and Badenian flo- ing clay marl sediments preserving the plant ras of Hungary. There are several specimens fossils belong to the Feked Formation, Komló in the Miocene flora of Verőce (Hungary; Hably Claymarl Member, dated as Karpatian (late in progress). It occurs in several European Burdigalian) (Sebe et al., 2019). Tertiary floras as Equisetum sp. (Bohemian Massif; Akhmetiev et al., 2009). MATERIAL AND METHODS Pteridopsida The fossil specimens are predominantly leaf impressions, but fruits and seeds, mainly winged Polypodiales ones, also frequently occur. Impressions are generally well preserved in the fish-scale marl owing to the fine- Blechnaceae grained sediment; however, cuticles are not preserved or are too poorly preserved for cuticular analysis. In Woodwardia muensteriana some cases, twigs with some leaves or rarely with leaf (C. Presl in Sternberg) Kräusel and fruit remains are observed. A fossil flower is an exceptional remain, with the stamens, both the theca Pl. 1, fig. 2 and filaments, having been fossilized, but no pollen is Pecopteris münsteriana preserved.