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Fragments of two skulls of young cetotheriid baleen whales were described from the Fortep'yanka 2 locality (Russia, Republic of Adygea, Maikop district, Fortep'yanka River valley, Upper Miocene, Upper Sarmatian, Blinovskaya Formation). The finds were attributed to Kurdalagonus maicopicus (Spasskii, 1951) based on the morphology of the posterior (mastoid) process of the petrosal bone, the structure of the posterior edge of the temporal fossa, and the S-like shape of the supraoccipital ridges. The skull proportions and the degree of suture closure made it possible to determine the individual age of the whales within a year. New finds significantly complement the data on the structure of the sutures of the lateral wall of the skull and age-related variability of cranial morphology in representatives of the genus Kurdalagonus.

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Even though the records of Tetraploa spores from Mesozoic and Cenozoic sedimentary strata along with spore-pollen assemblages are numerous and well documented, no foliicolus Tetraploa macroconidia have been reported to date. Here, we report the first occurrence of conidia assignable to modern Tetraploa Berk. & Broome (Tetraplosphaeriaceae: Pleosporales: Dothideomycetes) on cuticular fragments of compressed monocot leaf recovered from the middle Siwalik sediments (Late Miocene; 12-8 Ma) of Himachal Himalaya, India. We determine their taxonomic position based on detailed macromorphological comparison with similar modern and fossil taxa and discuss their palaeoecological significance in terms of the present-day ecological conditions of modern analogues. This finding also represents an essential data source for understanding Tetraploa's evolution and diversification in deep time.

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Porcupines, members of the Hystricidae family, represent a unique group of herbivorous mammals. This study details the identification of a newly discovered mandible fragment of Hystrix primigenia, along with a right cheek tooth series from the middle Turolian Kemiklitepe-A fossil locality. While Hystrix fossils are found in numerous localities, the materials are often limited to a few dental fragments or isolated teeth, posing challenges to systematic investigations. The examination of this lower tooth series prompted a comprehensive review of all H. primigenia findings across Eurasia, shedding light on its adaptive characteristics over time and space. Our paleobiogeographical analysis indicates the absence of H. depereti in Late Miocene Türkiye, while the dispersal range of H. primigenia is broader than that of H. depereti in Eurasia. Additionally, the study delves into the discussion of H. primigenia and H. depereti findings in Eurasia, ultimately refining the categorization of Late Miocene Hystrix discoveries in Türkiye to two species: H. primigenia and H. kayae. Our review suggests the possibility of an additional H. kayae finding from Samos, Greece.

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Enamel thickness and distribution provide dietary insights in hominoids. Yet, three-dimensional (3D) enamel analysis of the Late Miocene Lufengpithecus from southwest China is lacking. We digitally reconstructed 68 unworn or lightly worn Lufengpithecus (L.) lufengensis molars using micro-computed tomography (micro-CT). Comparisons with modern humans, Homo erectus, extant/fossil Pongo, Pan, and Gorilla reveal L. lufengensis has "intermediate/thick" enamel, thicker than Pongo and Gorilla, but thinner than modern humans and H. erectus. In enamel distribution, relatively thicker enamel lies on the lingual cusps of the maxillary molars. The hypoconid, hypoconulid, and entoconid exhibit relatively thicker enamel compared to the metaconid and protoconid of the mandibular molars. L. lufengensis also exhibits an uneven pattern on the lingual and buccal walls. With relatively intermediate/thick enamel and distinctive distribution pattern, L. lufengensis may be able to respond to dietary variation in seasonal habitats.

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We have recovered disease-symptomatic monocot leaves from the middle Siwalik (late Miocene; 12-8 Ma) sedimentary strata of Himachal Pradesh, western Himalaya, India. Information about disease symptoms linked to fossil monocot leaves, however, is lacking. The present study therefore aims to elucidate their identity through the analysis of morphological characteristics of the plant pathogenic fungi (causal agent) associated with these disease symptoms. Black mildew disease caused by foliicolous fungal fossil-genus Meliolinites Selkirk ex Janson. and Hills (fossil Meliolaceae) is detected on infected host Siwalik monocot leaves. In the study presented here, we provide formal descriptions and illustrations for the fossil-genus. The pathogen Meliolinites is recognized by the presence of appressoria, phialides, mycelial seta, black non-ostiolate ascomata, and four-septate, five-celled ascospores. This is the first report of melioloid fungus causing black mildew disease on fossil monocot leaves. Here, we also reconstruct a possible disease cycle of black mildew pathogen on Siwalik monocot leaves. The in-situ evidence of Meliolinites on the monocot leaf cuticles indicates the possible existence of a biotrophic relationship in Himachal sub-Himalaya's ancient warm and humid tropical forest during the time of deposition.

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The aim of constructing 3D computer models of outcrops of the Mount Messenger Formation using unmanned aerial vehicle (UAV) drone technology was to enable better visualization and potential for analysis of deep-water sedimentary systems in Taranaki Basin, New Zealand. The Late Miocene-aged strata crop out along the north Taranaki coast of western North Island, New Zealand. The Mount Messenger Formation sandstone and siltstone beds are outstanding examples of deep-water sedimentary strata. These strata can be observed in outcrop sections, as well as in offshore drillholes (wireline logs) and in seismic reflection data acquired immediately offshore of the north Taranaki coastal section. In previous research undertaken on the Mount Messenger Formation in North Taranaki Basin, geologists used photographs and coupled these with observations and descriptions of strata in the field. Modern UAV drone technology now enables 3D perspectives to be obtained of outcrop sections, which greatly improves geometrical analysis of the rocks. This type of analysis, coupled with mapping of seismic reflection data in the immediate offshore area has enabled us to better understand the nature of Mount Messenger Formation deep-water sedimentary strata and to interpret the associated paleogeography with implications for energy resource exploration and evaluation. Using UAV drone photogrammetry, we acquired ∼3000 images of the Mount Messenger Formation outcrop at four locations along the north Taranaki coast. Drone surveys were conducted using a real-time kinetic (RTK) global positioning system (GPS) for accurate geolocation. The surveys were conducted on a DJI Phantom 4 drone, with a focal length of 24 mm with a 20-megapixel resolution. Survey images overlapped by 80-90%. The drone work adhered to the rules and regulations of the Aviation Security Service and the University of Waikato, New Zealand. Images were captured using programmed flight paths where the drone faced the outcrops at distances ranging from ∼3-7 m. 3D computer models were constructed using Pix4Dmapper version 4.4.12 to generate dense 3D point clouds, digital surface models (DSMs), triangle meshes, and orthomosaic images of the outcrops (i.e., 3D models). Once the 3D computer models of the outcrops were constructed, they were exported out of Pix4Dmapper as ArcGIS Scene Layer Package format (.slpk) and loaded into ArcGIS Pro version 3.0.3 for further analysis. The 3D computer models comprise a rich and valuable scientific dataset that can enhance geological analysis of sedimentary strata beyond the capabilities of photographs and manual fieldwork. These models allow desktop analysis of the geology and "virtual fieldwork" by imaging areas that are commonly inaccessible on foot due to their high elevation above ground level, location in rugged and steep terrane, as well as periodic intertidal flooding. This electronic geological dataset is stored in commonly used spatial format and plain-text ASCII files, allowing the preservation of geological data in digital records, especially when the outcrops are prone to erosion and cover by vegetation. The drone model dataset can be reused by the scientific community for virtual geological fieldwork, as petroleum and water reservoir analogues, as well as for research on coastal, environmental and geotechnical topics.

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Equisetum (Equisetaceae) has long been a focus of attention for botanists and palaeontologists because, given its extensive and well-documented fossil record, it is considered the oldest extant vascular plant and a key element in understanding vascular plant evolution. However, to date, no authentic fossil evidence of Equisetum has been found from the Indian Cenozoic. Here, we describe a new fossil species, namely, E. siwalikum sp. nov., recovered from the middle Siwalik (Late Miocene) sediments of Himachal Pradesh, western Himalaya. We identified fossil specimens based on morphological and epidermal characters. In addition, X-Ray diffraction (XRD) analysis was used to determine the mineral composition of compressed stems of Equisetum. The close affinity of our recovered Siwalik fossils to Equisetum is supported by the presence of both macromorphological and epidermal characters. Because Equisetum generally grows in wet conditions around water reservoirs, our findings indicate that the fossil locality was humid and surrounded by swamp and lowland regions during deposition. Ample fossil evidence indicates that this sphenopsid once existed in the western Himalaya during the Siwalik period. However, at present Equisetum is confined to a particular area of our fossil locality, probably a consequence of severe environmental changes coupled with competition from opportunistic angiosperms. Our discovery of Equisetum fossils in appreciable numbers from the Siwalik sediments of the Himachal Himalayas is unique and constitutes the first reliable recognition of Equisetum from the Indian Cenozoic.

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Coprolites of the seal Pachyphoca volkodavi from the Upper Miocene deposits (Kherson) of the Fortepyanka locality (Republic of Adygea) were studied. Two out of five seal coprolites contained a structure resembling fish muscle tissue and included objects with morphology of trematode metacercariae. Obviously, the larvae of the parasite got into the digestive tract of seals from the fish they ate. Microscopic analysis of the coprolites did not reveal helminth eggs, which indicates possible absence of infection.

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We describe two large predators from the hominoid-bearing Khorat sand pits, Nakhon Ratchasima Province, northeastern Thailand: a new genus of pantherine, Pachypanthera n. gen., represented by partial mandible and maxilla and an indeterminate sabre-toothed cat, represented by a fragment of upper canine. The morphological characters of Pachypanthera n. gen., notably the large and powerful canine, the great robustness of the mandibular body, the very deep fossa for the m. masseter, the zigzag HSB enamel pattern, indicate bone-cracking capacities. The genus is unique among Felidae as it has one of the most powerful and robust mandibles ever found. Moreover, it may be the oldest known pantherine, as other Asian pantherines are dated back to the early Pliocene. The taxa we report here are the only carnivorans known from the late Miocene of Thailand. Although the material is rather scarce, it brings new insights to the evolutionary history of Neogene mammals of Southeast Asia, in a geographic place which is partly "terra incognita."

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The Çorakyerler fossil locality in Anatolia reveals unique faunal elements. This study introduces Hystrix kayae sp. nov., a new Late Miocene porcupine initially classified as Hystrix sp. Yavuz et al., 2018. This finding expands our knowledge of Late Miocene Anatolian porcupines, bringing the total number of known species to three. H. kayae sp. nov. is larger than Hystrix aryanensis and exhibits greater upper cheek tooth crown height. Its cheek tooth morphology differs from Hystrix depereti, and it possesses distinctive U-shaped choanae unlike Hystrix primigenia. The Çorakyerler locality may predate sites with H. aryanensis and H. primigenia but aligns temporally with Hystrix parvae localities. This study enhances our understanding of Late Miocene porcupine diversity in Anatolia, emphasizing the importance of Çorakyerler in unraveling the evolutionary history of these fascinating mammals.

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Dihoplus is a rhinoceros distributed across East Asia and Europe from the Late Miocene to Pliocene. This study describes a new skull from the Qin Basin in Shanxi Province, China, referred to as Dihoplus ringstroemi, which has long been debated in taxonomic identity. This skull confirms that D. ringstroemi is an independent species and reveals the presence of the upper incisor and variations in the degree of constriction of the two lingual cusps of upper cheek teeth. In addition, the new skull indicates that the Qin Basin has a late Neogene sediment and fauna comparable to that of the Yushe Basin.

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In parallel with pronounced cooling in the oceans, vast areas of the continents experienced enhanced aridification and restructuring of vegetation and animal communities during the Late Miocene. Debate continues over whether pCO2-induced global cooling was the primary driver of this climate and ecosystem upheaval on land. Here we present an 8 to 5 Ma land surface temperatures (LST) record from East Asia derived from paleosol carbonate clumped isotopes and integrated with climate model simulations. The LST cooled by ~7 °C between 7.5 and 5.7 Ma, followed by rapid warming across the Miocene-Pliocene transition (5.5 to 5 Ma). These changes occurred synchronously with variations in alkenone and Mg/Ca-based sea surface temperatures and with hydroclimate and ecosystem shifts in East Asia, highlighting a global climate forcing mechanism. Our modeling experiments additionally demonstrate that pCO2-forced cooling would have altered moisture transfer and pathways and driven extensive aridification in East Asia. We, thus, conclude that the East Asian hydroclimate and ecosystem shift was primarily controlled by pCO2-forced global cooling between 8 and 5 Ma.

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Introduction: East Asia (EA), which falls within the region of the Asian monsoon that is composed of the East Asia monsoon (EAM) and the Indian monsoon (IM), is known for its high species diversity and endemism. This has been attributed to extreme physiographical heterogeneity in conjunction with climate and sea-level changes during the Pleistocene, this hypothesis has been widely proven by phylogeographic studies. Recently, dated phylogenies have indicated that the origins (stem age) of the flora occurred after the Oligocene-Miocene boundary and are related to the establishment of the EAM. Methods: Hence, this study further examined whether the strengthening of the monsoons triggered floral evolution via a meta-analysis of the tempo-spatial pattern of evolutionary radiation dates (crown ages) of 101 endemic seed plant genera. Results: Taxonomic diversification began during the late Eocene, whereas the accumulated number of diversifications did not significantly accelerate until the late Miocene. The distribution of the weighted mean and the average divergence times in the EAM, IM, or transitional regions all fall within the mid-late Miocene. Fossils of the Tertiary relict genera are mostly and widely distributed outside EA and only half of the earliest fossils in the EA region are not older than Miocene, while their divergence times are mostly after the late Miocene. The pattern of divergence time of monotypic and polytypic taxa suggest the climatic changes after the late Pliocene exert more influence on monotypic taxa. Discussion: The two key stages of floral evolution coincide with the intensifications of the EAM and IM, especially the summer monsoon which brings a humid climate. An integrated review of previous studies concerning flora, genus, and species levels further supports our suggestion that monsoon intensification in EA triggered the evolution of its flora.

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The modern Pacific Ocean hosts the largest oxygen-deficient zones (ODZs), where oxygen concentrations are so low that nitrate is used to respire organic matter. The history of the ODZs may offer key insights into ocean deoxygenation under future global warming. In a 12-My record from the southeastern Pacific, we observe a >10‰ increase in foraminifera-bound nitrogen isotopes (15N/14N) since the late Miocene (8 to 9 Mya), indicating large ODZs expansion. Coinciding with this change, we find a major increase in the nutrient content of the ocean, reconstructed from phosphorus and iron measurements of hydrothermal sediments at the same site. Whereas global warming studies cast seawater oxygen concentrations as mainly dependent on climate and ocean circulation, our findings indicate that modern ODZs are underpinned by historically high concentrations of seawater phosphate.

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The evolution of subtropical evergreen broadleaved forests (EBLFs) in East Asia is interesting while complicated. Genus-level phylogenies indicate that the origins of EBLFs could trace back to the Oligocene-Miocene boundary or even the Eocene, while population-level phylogeographic evidence suggests that they diversified after the Miocene, particularly in the Pleistocene. Here, we review the origins of dominant plant species to better understand the evolution of EBLFs. We compiled published estimates of the timing of origin of dominant species and diversification of evergreen relict genera from East Asian EBLFs. We also traced and visualized the evolution of EBLFs in the region using dated phylogenies and geographic distributions of the reviewed taxa. Most (76.1%) of the dominant species originated after the late Miocene, ca. 8 million years ago. Of the 10 evergreen relict genera, eight diverged near the late Miocene-Pliocene boundary or during the late Pliocene, and the remaining two diverged during the Pleistocene. Over the past 8 million years, geo-climatic changes have triggered origins of most of the dominant EBLF species and provided refugia for evergreen relict genera. Three pulsed phases of evolution are suggested by genetic studies at the genus, species, and population levels. Fossil evidence and spatiotemporal investigations should be integrated to fully understand the evolution of EBLFs in East Asia.

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Choerospondias (Anacardiaceae), characterized by radially arranged germination pores near the top, is a monotypic genus mainly distributed in subtropical and tropical eastern Asia, while fossil records indicate a wide distribution throughout Eurasia during the Cenozoic. In this study, we reported three-dimensionally preserved Choerospondias endocarps, and the associated compressed leaves from the late Miocene Shengxian Formation in Tiantai, Zhejiang, eastern China. The plant remains were assigned to two new fossil species. The endocarps were identified as Choerospondiastiantaiensis sp. nov., and the leaves were identified as Choerospondias mioaxillaris sp. nov. Based on fossil records and climate fluctuation during the Cenozoic, we conclude that Choerospondias may have originated from Europe in the early Eocene and then spread to Asia along the coast and island chains of the Tethys and Paratethys oceans. The distribution position of the current fossils was adjacent to the northern boundary of the modern distribution of Choerospondias in East Asia, indicating that the distribution pattern of Choerospondias in East Asia likely formed no later than the late Miocene. We reconstructed the late Miocene paleoclimate of eastern Zhejiang by using the method of climate analysis of endemic species (CAES), and then compared it to the data reconstructed in previous studies. The results indicate that the late Miocene climate in eastern Zhejiang was similar to or warmer and more humid than the modern climate in this region.

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The global herbaceous flora is probably shaped by both ancient and/or recent diversification, companied with the impacts from geographic differences between the Northern and Southern Hemispheres. Therefore, its biogeographic pattern with respect to temporal and spatial divergence is far from full understanding. Tribe Rubieae, the largest herbaceous tribe in the woody-dominant Rubiaceae, provides an excellent opportunity for studying the macroevolution of worldwide colonization. Here, we aim to reconstruct the evolutionary history of Rubieae with regard to climate fluctuation and geological history in the Cenozoic. A total of 204 samples of Rubieae representing all the distribution areas of the tribe were used to infer its phylogenetic and biogeographic histories based on two nrDNA and six cpDNA regions. The ancestral area of Rubieae was reconstructed using a time-calibrated phylogeny in RASP and diversification rates were inferred using Bayesian analysis of macroevolutionary mixtures (BAMM). Our results show Rubieae probably originated in European region during the middle Oligocene, with the two subtribes separating at 26.8 million years ago (Ma). All the genera in Rubieae formed separate clades between 24.79 and 6.23 Ma. The ancestral area of the subtribe Rubiinae was the Madrean-Tethyan plant belt and the North Atlantic land bridge (NALB) provided passage between North America and Europe for Rubiinae. The subtribe Galiinae clade originated in Europe/central Asia during the late Oligocene. Two diversification shifts were detected within Rubieae in the late Neogene. Most extant Rubieae species diverged recently during the Neogene within clades that generally were established during the late Paleogene. The tribe shows complex migration/dispersal patterns within the North Hemisphere combined with multiple recent dispersals into Southern Hemisphere. Our results highlighted the important role of recent biogeographic diversification in the Northern Hemisphere in shaping the modern global herbaceous flora during the latest and rapid worldwide expansion in the Neogene.

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Emphytusmiocenicus sp. nov., first fossil representative of this genus, is described from the upper Miocene of the diatom paleolake of Montagne d'Andance (Ardèche, France). Its placement is ensured by an in-depth comparison with all the extant and fossil genera of the subfamily Allantinae. The representatives of Emphytus are distributed in the Palearctic, Nearctic, and Oriental regions. Empria sammuti sp. nov., second representative of the latter genus, is described from the latest Miocene of the diatom paleolake of Sainte-Reine (Cantal, France). The placement of this new species is based on a detailed comparison with the extant genera of the tribe Empriini. The larvae of the extant Emphytus and Empria spp. are known to be phytophagous on angiosperm leaves of several families, all present as fossils in the taphocenoses of la Montagne d'Andance and Sainte-Reine. Emphytus miocenicus sp. nov. represents the oldest record of this genus and of its crown group, corroborating the estimate of a middle Eocene-middle Oligocene age for its stem group. Throughout our study, it appears that the first described fossil of the genus Empria, E. oligocaenica, from the Oligocene of Germany, needs to be revised and redescribed. It should preferably be treated until the revision as incertae sedis in Allantinae sensu lato.

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The Eastern and Western Mediterranean are separated by an elevated plateau that regulates water exchange between these two basins. The Maltese archipelago, situated atop this topographic high, offers a unique window into the evolution of this plateau in the lead up to the Messinian Salinity Crisis. The Upper Coralline Limestone Formation was deposited between the late Tortonian and the early Messinian and was probably terminated by palaeoceanographic events related to the Messinian Salinity Crisis. It represents the youngest Miocene sedimentary deposits outcropping in the Maltese archipelago. This shallow-water carbonate unit can be used to trace palaeoenvironmental changes atop the sill between the Eastern and Western Mediterranean and to explain the possible water flow restrictions to the Eastern Mediterranean that could have preceded the Messinian Salinity Crisis. Here field surveys, and analysis of the depositional environment within the Upper Coralline Limestone in Malta, are combined with recently acquired multichannel seismic reflection profiles between Malta and Gozo, to reconstruct the depositional sequence in the Malta Plateau during the late Miocene. The Upper Coralline Limestone consists of multiple coralline and larger benthic foraminifera dominated facies, extending from subtidal to intertidal environments. These accumulated in two depositional cycles observed in both outcrop and seismic reflection data. Each cycle exhibits an early aggradation-progradation phase followed by a progradation phase and a final aggradation phase. These manifest themselves in the outcrops as shallowing and deepening upwards phases. These were deposited above a deep water unit and are indicative of a preceding uplift phase followed by filling of the accommodation space through the deposition of the Upper Coralline Limestone Formation in shallow marine depths. The presence of this highly elevated sill during the late Miocene could have restricted circulation to the eastern basin.