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The early Burdigalian (MN3) plant assemblage of the Güvem area (northwestern Central Anatolia) is preserved in lacustrine sediments of the Dereköy pyroclastics. Its age is well constrained by radiometric dates of basaltic rocks bracketing the pyroclastics, making the Güvem flora one of the extremely few precisely dated early Miocene floras in the Mediterranean region. The rich assemblage of impression fossils comprises ferns and fern allies (2 species), gymnosperms (12 spp.) and angiosperms (129 spp.). Ilex miodipyrena sp. nov. is described as a new fossil-species. The most diverse families in the assemblage are the Fagaceae with 12 taxa and the Fabaceae with 12 leaf morphotypes and one fruit taxon. Aquatic plants are represented by seven taxa, riparian (including palms) and swamp forest elements by >35 taxa, and lianas by three taxa (Smilax spp., Chaneya). The relatively large number of aquatic and riparian/swamp elements is congruent with the rich fish, amphibian and reptile record of the Güvem area. Another characteristic feature of the plant assemblage is the presence of various lobed leaves which show similarities with modern species of different families (e.g. Alangium, various Malvales). Trees and shrubs growing on well-drained soils and forming closed-canopy and open-canopy forests are the most diversified group (>70 taxa). In terms of number of specimens in the collection and based on field observations, by far the most abundant leaf fossils belong to evergreen oaks of Quercus drymeja and Q. mediterranea and to various types of foliage that cannot be assigned to a particular extant or extinct genus of Fagaceae. These sclerophyllous trees must have covered vast areas surrounding the wetlands that developed during the early Miocene in the Güvem Basin. Based on a recent reassessment of the ecology and taxonomic affinity of these trees, they are considered to reflect humid temperate climatic conditions but with a brief drier season during the winter months. These forests are more similar to the laurel forests of the southeastern United States and those stretching in a narrow belt south of the Himalayas to eastern central China. The large number of Fabaceae may indicate the presence of warm subtropical environments but this is difficult to assess, as they are known for having wide ecological ranges today and in the past. All in all, a larger part of the plant taxa point to forested vegetation. This is in agreement with previous palynological studies which detected only small amounts of herbaceous and grass pollen. Open patches of vegetation may have been restricted to river banks and to rocky areas in a volcanic landscape. The biogeographic patterns detected for the early Miocene of the Güvem assemblage are manifold; most taxa are widespread Northern Hemispheric elements. A substantial part of the species migrated from Asia into Europe during the (late) Paleogene and reached Anatolia during the early Miocene (Fagus, Paliurus, Chaneya, Ailanthus, Quercus kubinyii, Davallia haidingeri, Acer angustilobum, A. palaeosaccharinum). Fewer taxa may have been in Anatolia before they migrated to Europe (e.g. Nerium, Smilax miohavanensis, Quercus sosnowskyi). Finally, very few taxa are Anatolian endemics (e.g. Ilex miodipyrena). [ABSTRACT FROM AUTHOR]

Abstract: The genus Mahonia has a disjunct modern distribution with the New World Group Occidentales in northwestern North America and Central America and the mostly Old World Group Orientales in Central and Southeast Asia. Group Orientales has one species in North America. Morphologically, the two groups can be distinguished by two main patterns of leaf venation. Leaflets in the Group Orientales have a palmate-festooned brochidodromous venation and those of Group Occidentales usually have a pinnate-brochidodromous to (semi)craspedodromous venation, with some intermediate forms. In North America both Orientales and Occidentales can be traced from Eocene to Miocene strata. No unequivocal records of Mahonia are known from East Asia. A few Oligocene to Pleistocene fossils from Europe can be assigned to Group Orientales and to the section Horridae Fedde of Group Occidentales. Here we report two new species of Mahonia from the Miocene of Turkey, which clearly fall within the morphological range of the Group Orientales. One species, also found in the Oligocene–Miocene of western North America, is quite similar to Himalayan and East and Southeast Asian modern species. The other resembles the single modern North American member of Group Orientales. The high diversity of Mahonia in Europe and Asia Minor from the Oligocene onwards includes members of at least four lineages. The close relationships of these fossils with contemporary North American species suggest that the genus had reached western Eurasia from North America via the North Atlantic during or prior to the Oligocene. Colonization of Central and East Asia may have occurred from western Eurasia or North America, or from both directions. [Copyright &y& Elsevier]

Sclerophyllous oaks (genus Quercus ) play important roles in Neogene ecosystems of south-western Eurasia. Modern analogues (‘nearest living relatives’) for these oaks have been sought among five of six infrageneric lineages of Quercus , distributed across the entire Northern Hemisphere. A revision of leaf fossils from lower Miocene to Pliocene deposits suggests that morphotypes of the Quercus drymeja complex are very similar to a number of extant Himalayan, East Asian, and Southeast Asian species of Quercus Group Ilex and may indicate subtropical, relatively humid conditions. Quercus mediterranea comprises leaf morphotypes that are encountered in modern Mediterranean species of Quercus Group Ilex, but also in Himalayan and East Asian members of this group indicating fully humid or summer-wet conditions. The fossil taxa Quercus drymeja and Q. mediterranea should be treated as morphotype complexes, which possibly comprised different biological species at different times. Quercus mediterranea , although readily recognizable as a distinct morphotype in early to late Miocene plant assemblages, may in fact represent small leaves of the same plants that constitute the Quercus drymeja complex. Based on the available evidence, the species forming the Q. drymeja complex and Q. mediterranea thrived in fully humid or summer-wet climates. The onset of the modern vegetational context of Mediterranean sclerophyllous oaks is difficult to trace, but may have been during the latest Pliocene/early Pleistocene. [ABSTRACT FROM AUTHOR]

Ecosystems are defined by the community of living organisms and how they interact together and with their environment. Insects and plants are key taxa in terrestrial ecosystems and their network determines the trophic structure of the environment. However, what drives the interactions between plants and insects in modern and fossil ecosystems is not well understood. In this study, we analyzed insect damage richness and frequency in 5000 fossil leaves deposited during the early Miocene at 20–17 Ma along a latitudinal gradient from Europe (two localities in Czech Republic) to Turkey (one locality) in a temperate climate setting. Damage frequency was mainly linked with abiotic factors (temperature, precipitation seasonality) whereas damage richness was mainly linked with biotic factors (plant richness, biome). Univariate analysis of insect damage types consistently suggested closer trophic similarity between the Mediterranean and either the one or the other Central European plant assemblage. In contrast, multivariate analysis of all insect damage types indicated closer similarity between the two Central European sites highlighting the importance of biogeographic legacy and geographic closeness to the plant-insect interaction patterns. Our results underscore the high complexity of the herbivory network and call for careful interpretations of plant-insect interaction patterns in palaeoecological studies. Finally, comparing the trophic similarity between different localities using total evidence plots as done in this work might be a promising complementary method in comparative studies of plant-insect interactions. • We compared insect damage types in Miocene leaf floras of Turkey and Czech Republic • DT richness was higher in subhumid laurel (TR) than mixed-mesophytic forest (CZ) • Damage frequency was linked to abiotic factors (t°, precipitation seasonality) • Damage richness was linked to biotic factors (species richness, biome) • A multivariate analysis of all DT richness recorded a strong geographic signal [ABSTRACT FROM AUTHOR]