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1.
The fossil leaf flora from the Shanwang Formation, Linqu County, Shandong Province, eastern China, is diverse, abundant, well preserved and discretely spaced, all of which make it suitable for the recognition and application of leaf physiognomic characters. This article is the first study of Chinese Tertiary floras using the CLAMP (Climate Leaf Analysis Multivariate Program) approach. Numerous bedding planes yield leaf assemblages through over 20 m thickness of diatomaceous shales within the Middle Miocene Shanwang Formation. The diatomaceous shales, containing abundant fossils, have been divided into 19 units. A working platform (3×3 m) in the Diatomite Quarry of Shanwang was studied for about 3 months in 1998 and as many fossils as possible were recorded layer by layer. This collecting method, used for the first time in the history of Shanwang research, enabled us to record the presence or absence of megafossils in distinct units so that we could investigate leaf physiognomic characteristics and palaeoclimate for each time interval. Leaf fossils from six units (5, 6, 7, 13, 15 and 16) have been used to estimate palaeoclimate parameters of the Shanwang area using the CLAMP 3B dataset. The predicted climate is that of a lakeside setting, at over 1000 m above sea level and within the 17–15-Ma time interval. Meteorological factors have been estimated using the CLAMP approach, including mean annual temperature (MAT; 9.5–11.2°C), warmest month mean temperature (20.2–22.5°C), growing season length (5.9–6.8 months), mean growing season precipitation (83–165 cm) and relative humidity (73–79%). MAT estimates from leaf margin analysis (LMA) range from 12.5 to 15.2°C, which are a maximum of 4° higher than those from our CLAMP analyses and from previous results of LMA studies of the Shanwang flora (10–13°C). Nearest living relatives (NLR) of other biota (pollen, fish, insects, diatoms, microthyriaceous fungi, etc.) indicate warm and moist temperate to subtropical conditions in the Shanwang area during the Miocene. CLAMP predictions are similar to the climate predicted from NLRs although the MAT prediction is a few degrees cooler. The fact that the Shanwang leaf flora is from a lacustrine sequence may have biased the CLAMP analysis towards cooler (and possibly wetter) climates. The modern Yangtze River valley is a reasonable environmental analogue for the Shanwang Middle Miocene, though Shanwang may have had cooler summers, cooler MAT and less seasonality in rainfall. The climate was essentially constant during deposition of the sequence studied, with possible minor variations in precipitation.  相似文献   

2.
Fossil evidence for the evolutionary history of terrestrial arthropods in New Zealand is extremely limited; only six pre‐Quaternary insects (Triassic to Eocene) have been recorded previously, none of Miocene age. The Foulden Maar fossil lagerstätte in Otago has now yielded a diverse arthropod assemblage, including members of the Araneae, Plecoptera, Isoptera, Hemiptera, Coleoptera, Hymenoptera, Trichoptera and Diptera. The fauna significantly emends the fossil record for the Southern Hemisphere, provides an unparalleled insight into a 23‐million‐year‐old New Zealand lake/forest palaeoecosystem and allows a first evaluation of arthropod diversity at a time coeval with or shortly after the maximum marine transgression of Zealandia in the late Oligocene. The well‐preserved arthropods chiefly represent ground‐dwelling taxa of forest floor and leaf litter habitats, mostly from sub‐families and genera that are still present in the modern fauna. They provide precisely dated fossil evidence for the antiquity of some of New Zealand's terrestrial arthropods and the first potential time calibrations for phylogenetic studies. The high arthropod diversity at Foulden Maar, together with a subtropical rainforest flora and fossil evidence for complex arthropod–plant interactions, suggests that terrestrial arthropods persisted during the Oligocene marine transgression of Zealandia.  相似文献   

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4.
The early middle Miocene biota from the Shanwang locality in eastern China is one of the most diverse and well preserved in the world. This overall richness contrasts with its low diversity of anuran amphibians. The most abundant anurans are representatives of the family Ranidae, which remains the dominant group in the extant anuran fauna of China. Besides Rana basaltica Young, some other ranids can be recognised at the locality, and are clearly distinguishable from R. basaltica based on their larger size and different proportions. Ranids are also represented by a developmental series of tadpoles, ranging from approximately Nieuwkoop-Faber (NF) stage 43 to a metamorphosing tadpole of NF stage 57. This is the first known developmental series of fossil non-pipoid Anura outside the Pelobatidae. In addition to the ranids, Bufo shandongensis nov. sp. (replacement name for B. linquensis), represented by one of the earliest known articulated bufonid skeletons, is described and illustrated. Another large toad, Macropelobates linquensis (Yang) nov. comb., is re-described; it can be assigned to the Pelobatoidea, with a possible relationship to the Scaphiopodidae, and can be considered, based on the presence of a large spade, a tibiofibula shorter than the femur, and a short astragalus and calcaneus, to be the earliest known anuran burrower.  相似文献   

5.
Abstract:  Three new genera and four new species of the extinct mantidfly subfamily Mesomantispinae (Insecta: Neuroptera: Mantispidae) are described from the Lower Cretaceous Yixian Formation of Liaoning and the Middle Jurassic Jiulongshan Formation of Inner Mongolia: Archaeodrepanicus nuddsi gen. et sp. nov., A. acutus gen. et sp. nov., Sinomesomantispa microdentata gen. et sp. nov., (Yixian Formation) and Clavifemora rotundata gen. et sp. nov. (Jiulongshan Formation). The specimens described herein represent the first Mesozoic mantidfly compression fossils to have body parts preserved, including the specialized raptorial forelegs articulated to the prothorax anteriorly, an autapomorphy of the family. These new taxa further confirm the placement of the subfamily Mesomantispinae within the family Mantispidae; however, the monophyly of Mesomantispinae has not been confirmed, and it is likely that it will prove to be paraphyletic.  相似文献   

6.
An updated reconstruction of the body plan, functional anatomy and life attitude of the bradoriid arthropod Kunmingella is proposed, based on new fossil specimens with preserved soft parts found in the lower Cambrian of Chengjiang and Haikou (Yunnan, SW China) and on previous evidence. The animal has a single pair of short antennae pointing towards the front (a setal pattern indicates a possible sensory function). The following set of seven appendages (each composed of a 5-segmented endopod and a leaf-like exopod fringed with setae) is poorly differentiated, except the first three pairs (with possible rake-like endopodial outgrowths, smaller exopods) and the last pair of appendages (endopod with longer and more slender podomeres). The endopods are interpreted as walking legs with a possible role in handling food particles (marginal outgrowth with setae). The leaf-like exopods may have had a respiratory function. The trunk end is short, pointed, flanked with furcal-like rami and projects beyond the posterior margin of the carapace. The attachment of the body to the exoskeleton is probably cephalic and apparently lacks any well-developed adductor muscle system. The inferred life attitude of Kunmingella (e.g. crawling on the surface of the sediment) was that of a dorsoventrally flattened arthropod capped by a folded dorsal shield (ventral gape at least 120°), thus resembling the living ostracode Manawa. The animal was also probably able to close its carapace as a response to environmental stress or to survive unfavourable conditions (e.g. buried in sediment). The anterior lobes of the valves are likely to have accommodated visual organs (possibly lensless receptors perceiving ambient light through the translucent head shield). Preserved eggs or embryos suggest a possible ventral brood care. The presence of Kunmingella in coprolites and its numerical abundance in Chengjiang sediment indicate that bradoriids constituted an important source of food for larger predators. Kunmingella differs markedly from the representatives of the crown group Crustacea (extant and Cambrian taxa) and from the stem group derivatives of Crustacea (exemplified by phosphatocopids and some ‘Orsten’ taxa) in showing no major sign of limb specialization (e.g. related to feeding strategies). Although it resembles other Chengjiang euarthropods in important aspects of its body plan (e.g. uniramous antennae, endopod/exopod configuration), Kunmingella possesses several features (e.g. antennal morphology, post-antennular appendages with 5-segmented endopods) which support the view that bradoriids may be very early derivatives of the stem line Crustacea.  相似文献   

7.
The fossil record of the Tabanidae is sparse when compared with other families of Diptera. Even in amber they are rare, probably because of their size and specific flight behavior. Horseflies from amber are only known from Cretaceous age New Jersey amber as well as from the Tertiary age Baltic and Dominican amber, but are herein described for the first time, with Stenotabanus oleariorum sp. n., from Mexican amber. The new species is compared to the fossil horseflies of the same genus S. brodzinskyi Lane, Poinar and Fairchild 1988 and S. woodruffi Lane and Fairchild 1989 from Dominican amber.  相似文献   

8.
The palynological analysis of the Burdigalian (Early Miocene) successions of the Güvem Basin (NW Central Anatoia, Turkey) has been carried out with the aim of reconstructing the palaeovegetation. The pollen spectra indicate a flora dominated by trees such as Quercus deciduous type, Carya, Carpinus, Ulmus/Zelkova, Engelhardia, Quercus ilex type and Pinaceae. Pterocarya, Juglans, Alnus, Salix, Liquidambar and Oleaceae are represented by lower percentages. Herbs and shrubs are represented by minor amounts of Poaceae, Amaranthaceae/Chenopodiaceae, Asteraceae/Asteroideae, Brassicaceae, and the aquatics Potamogeton, Sparganium and Typha. The Burdigalian flora reflects a mixed mesophytic forest with Quercus deciduous type, Quercus ilex type, pine species, Ulmus/Zelkova, Engelhardia, Carya, Carpinus, Pterocarya, etc., sparcely interspersed with open herbaceous areas. This flora reflects a warm-temperate climate. The fluctuations in abundances of broadleaved trees and xerophytes may represent fluctuations of relatively wet and dry periods. The overall composition of the flora of the Güvem Basin reflects cooler conditions compared with other Early Miocene floras in Europe, which is possibly due to intense volcanic activity of the area.  相似文献   

9.
The origin and evolution of angiosperms can be unravelled by using fossil records to determine first occurrences and phytogeographic histories of plant families and genera. Many angiosperm families, for example the Onagraceae, have a poor macrofossil record, but are more common in palynological records. Modern Onagraceae produce pollen clearly distinct from that of other angiosperms. Combined morphological features obtained by use of light and scanning electron microscopy have enabled assignment of fossil Onagraceae pollen to extant genera, and therefore tracing of the origin and past distributions of extant Onagraceae lineages. We studied a Miocene palynoflora from the Daotaiqiao Formation of north-east China. Using the single-grain technique, we examined individual Onagraceae pollen/tetrads using both light and scanning electron microscopy. Fossil Onagraceae pollen is more frequent than macrofossil remains, but is still rare, and usually represented by a single taxon in palynological samples. Remarkably, samples from the Miocene of north-east China contain five different species: two of Circaea, one of Epilobium, and two of Ludwigia. Such a large number of Onagraceae taxa from a single palynoflora is unknown elsewhere. Whereas Ludwigia pollen is known from Cenozoic sediments of the northern hemisphere, the Circaea pollen is the first fossil pollen assignable to this extant genus. This is also the first fossil record of Epilobium from China. Although the young geological age of this sample does not enable consideration of time of origin for the genera encountered, the co-occurrence of Circaea, Epilobium, and Ludwigia in the mid to late-Miocene of East Asia sheds some light on their phytogeographic histories.  相似文献   

10.
根据产自广西南宁盆地渐新世早-中期的鳅科鱼类眼下刺化石建立了鳅属新种:南宁鳅+Cobitis nanningensis sp.nov.。眼下刺长1.8~3.0 mm,粗细适中,刺二分叉,侧后突较中后突短而细,长度约为中后突长的1/3,侧突发育。这些眼下刺与德国晚渐新世的+Cobitis primigenus最为相似,但又以侧突更为发育而与之区别。这是迄今最早的鳅科化石记录,为了解早期鳅科鱼类的分布和眼下刺的形态特征提供了有益证据。南宁鳅及德国晚渐新世的+C.primigenus揭示,渐新世时期鳅科鱼类已广布于欧亚大陆。  相似文献   

11.
Marly sediments of the early Messinian Abad Member of the Turre Formation from the northeastern sector of the Carboneras-Nijar Basin (southern Spain) have yielded a rich fossil assemblage, of which 60 taxa are documented herein. Besides nannoflora and microfauna, this assemblage includes the first autochthonous macrofauna described from the Abad Member. Based on the calcareous nannofossil assemblage, in particular the occurrence of the zonal index taxon Amaurolithus primus, the sediments are assigned to the Mediterranean calcareous nannofossil zone CNM17, corresponding to the latest Tortonian to earliest Messinian interval. This matches the age range generally reported for the Abad Member. Palaeoecological evidence from calcareous nannofossils (20 autochthonous taxa), planktic and benthic foraminifera (12 taxa), Porifera (3 taxa), Octocorallia (Keratoisis), Serpulidae (4 taxa), Bivalvia (5 taxa), Gastropoda (2 taxa), Brachiopoda (7 taxa), Cirripedia (Faxelepas) and Vertebrata (5 taxa) indicates an upper bathyal environment with an influx of neritic elements for the Abad Member near Carboneras. Additionally, several faunal components may represent allochthonous/parautochthonous elements from adjacent habitats, which were transported into the deep marine setting by turbiditic mass flows. Although similarities exist, the fossil assemblage from the marls is compositionally significantly different from the biota previously documented from a nearby exposed olistostrome, the ‘red breccia’. Similar fossil assemblages from the Mediterranean have so far mainly been reported from the Pliocene-Pleistocene of southern Italy and Greece. The Carboneras fauna thus adds to our knowledge of the development of these habitats and their biota prior to the Messinian salinity crisis. Beyond the novel palaeoenvironmental data, the range of the dyscoliid brachiopod Ceramisia meneghiniana, previously known only from the Pliocene of Italy, is extended to the Miocene of Spain. The cirripede crustacean Pycnolepas paronai De Alessandri, 1895 is transferred to the hitherto monospecific genus Faxelepas Gale, 2015, whereby the range of the latter (previously Maastrichtian to Danian) is extended to the late Miocene.  相似文献   

12.
An integrated stratigraphic study of a Neogene lacustrine succession on the Pag Island (Croatia), combining quantitative pollen analysis, magnetostratigraphy, cyclostratigraphy, biostratigraphy and gamma-ray measurements, provides new insights into orbitally controlled variations in palaeo-vegetation and depositional patterns in the Dinaride Lake System. The quantitative palynological record shows a cyclical pattern of vegetation changes that closely corresponds to sedimentological patterns. The intervals with a high abundance of thermophilous and xeric indicators, suggesting a warm and dry climate, generally coincide with intervals of frequent lignite deposition and shallow lake facies. This suggests that both records are dominantly controlled by variations in past climatic conditions and lake level. Our data show two large-scale warming and shallowing-upward cycles, which are interpreted to be forced by the ~ 100 kyr eccentricity cycle of the Earth's orbit. Magnetostratigraphic data of the examined section reveal a long (113 m) reversed polarity interval, followed by a 7 m thick interval of normal polarity at the top. The inferred depositional rate of ~ 0.3 mm/yr, combined with biostratigraphic constraints by mollusks, suggests that the most logical correlation of the reversed interval is to chron C5Cr. This indicates that the Pag succession was deposited between 17.1 and 16.7 Ma and that it corresponds to the Burdigalian Stage of the Early Miocene, and the regional Karpatian Stage of the Central Paratethys. The high relative percentage of thermophilous pollen taxa, Engelhardia and Taxodium-type being the most prominent, generally indicates a subtropical humid climate for the SW Croatian part of the Dinaride Lake System. The observed warming trend is possibly related to the onset of the Miocene Climatic Optimum.  相似文献   

13.
Pollen analysis of a Lower Miocene succession from the Rubielos de Mora Basin (NE Spain) has been carried out with the aim of reconstructing the flora, vegetation and climatic changes. Previous paleobotanical studies on these sedimentary rocks and adjacent areas interpreted very diverse climates for the Early Miocene: from humid temperate to dry subtropical. In this study, a rich thermophilous pollen spectrum and a diverse subarid flora including Nitraria, Caesalpiniaceae, Ephedra and Acacia, indicative of a dry subtropical climate are identified. On the other hand, mesothermic taxa with high water requirements are also abundant. Therefore, the pollen assemblages evidence the juxtaposition of very contrasted environments: the presence of subdesertic taxa, typical of plants growing in the lowlands and conditioned by a long warm, dry season, together with others with very high water requirements, needing constant water. This can be explained by the presence of the Rubielos de Mora Lake providing local conditions for developing riparian forests. The vegetation was clearly controlled by the water availability under a subtropical and dry-seasonal climate. Pollen changes along the succession, which coincide with sedimentological changes, are related to climatic variations. Alternation in pollen taxa (thermophilous–dry vs. mesothermic–riparian) reflects the influence of the cyclicity of temperature and precipitation on the lake level and vegetation.  相似文献   

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15.
A new vertebrate faunal assemblage was recently discovered from the uppermost part of the late Miocene Puerto Madryn Formation. These deposits crop out along the southwestern coast of the Península Valdés area near Punta Delgada (Chubut Province, Argentina). The exhumed vertebrate fauna includes a range of fish, bird and mammal taxa, of which the latter are most varied and abundant. The new findings represent the first record of continental fossil vertebrates in the Puerto Madryn Formation and this is the first assemblage of late Miocene continental vertebrates recorded to the south of Río Negro Province. It also includes the southernmost record of Hydrochoeridae rodents, Dendrocygninae birds and Loricariidae fishes. The mammals suggest that the fossil-bearing sediments are Huayquerian in age. The climate during the accumulation of late Miocene deposits in this region is inferred to have been warmer and seasonally drier than that of today.  相似文献   

16.
Fossil fruits including nuts and associated husk valves of a new species of Carya (Juglandaceae) are described from the latest Miocene to earliest Pliocene in northeastern Tennessee, eastern United States. The husk valves are elliptic, 1.2–4.5 mm thick, with a convex exterior face and a concave interior face; the nuts are globose to ovoid in shape, smooth and longitudinally ribbed on exterior surface, with a short protruding apex and a slightly 4-angled base; inner ribs, lacunae and primary septa are well-developed, while secondary septa are absent or weakly developed. The combination of these carpological characteristics clearly shows a close resemblance to the genus Carya in Juglandaceae. Detailed comparisons of carpological morphology and anatomy indicate that the present fossil taxon is different from both living and most other fossil species of the genus, and therefore warrants the designation of a new fossil species, Carya tennesseensis Huang et al., sp. nov. Carya tennesseensis displays a carpological similarity to C. ventricosa from the late Oligocene to early Pliocene in Europe, suggesting a potential species exchange of the genus between Europe and southeastern North America during the late Neogene. The new fossil species represents one of the few fruit fossil species of Carya from its modern distribution range in southeastern North America. It provides crucial information for better understanding the rapid diversification of the genus from the late Miocene to early Pliocene, and the origin and establishment of today's Carya biodiversity in this region.  相似文献   

17.
《Palaeoworld》2020,29(3):453-461
A new exceptionally-preserved Cambrian biota, with fossils belonging to multiple phyla, has recently been found from the middle part of the Longha Formation, near Fulu Village, southeastern Yunnan, South China, and is named the Fulu biota. Groups recovered so far include polymerid trilobites, agnostoids, large bivalved arthropods, bradoriid arthropods, echinoderms, brachiopods, priapulids (worms), hyoliths, macroscopic algae, and trace fossils. The arthropods dominate the biota and are highly diverse with echinoderms second in diversity. The associated agnostoids provide a precise late Guzhangian Age (late Miaolingian Epoch) for the biota, indicating that the biota occurs stratigraphically about halfway between the occurrences of the Kaili and the Guole biotas of South China, from both of which the new Fulu biota differs significantly in faunal components. Guzhangian biotas preserving poorly mineralized tissues and complete echinoderms have been previously unknown in Gondwana until now; thus, the discovery of Fulu biota provides a unique window into life at this critical time interval.  相似文献   

18.
A diverse assemblage of unusually well-preserved marine, euryhaline, freshwater, and terrestrial fossils (invertebrates, vertebrates, and plants) occurs within an Upper Carboniferous (Stephanian) Konservat Fossil-Lagerstätte near Hamilton, Kansas, USA. The Lagerstätte occurs within a paleovalley that was incised into the surrounding Carboniferous cyclothemic sequence during a time of low sea level, and was then filled-in during a subsequent transgression. The stratigraphically lowest and most voluminous facies within the valley is a cross-bedded, polymictic limestone conglomerate that contains caliche clasts and charcoal fragments as well as some normal-marine fossils apparently in situ. The origin of the conglomerate is enigmatic, but it was probably deposited by a migrating tidal channel. Overlying and interbedded with the conglomerate is an ostracode wackestone that contains plants (primarily seed ferns and ferns), eurypterids, shrimp, brachiopods, bivalves, and rare fish. The ostracode wackestone was deposited in a low-energy, marginal-marine environment. A thin sequence (<1 m thick) of interbedded laminated limestone and mudstone overlies the conglomerate in a small area. This facies contains a well-preserved mixed assemblage of terrestrial (conifers, insects, myriapods, reptile), freshwater (ostracodes), aquatic (amphibians, reptile), brackish or euryhaline (ostracodes, eurypterids, spirorbids, fish), and marine (brachiopods, echinoderms) fossils. Many of the vertebrates are articulated and show no evidence of preburial decay, scavenging, or predation. A few vertebrates exhibit signs of flotation. Most articulated vertebrate specimens exhibit soft-tissue preservation in the form of dark-brown to black early-diagenetic microbialite body outlines (‘skin preservation’) containing fossil bacteria. Rhythmic patterns of lamination thickness variation in the limestones and mudstones indicate that this facies was deposited in a tidal environment. High sedimentation rate and variable salinity (and therefore exclusion of bioturbators and invertebrate scavengers) are interpreted as key elements that led to the excellent preservation of the fossils in this ancient estuarine environment. □Lagerstätte, taphonomy, estuarine, tidal bedding, paleovalley, Carboniferous, Kansas.  相似文献   

19.
We restudy the holotype specimen of the alleged fossil auk Petralca austriaca from early Miocene marine deposits of the Austrian locality Pucking, which was considered the earliest European representative of Alcidae (auks). The specimen is a partial skeleton consisting mainly of wing bones on two slabs. A recent re-preparation yielded new data on the skeletal morphology of Petralca, which allow more detailed comparisons with auks and loons. Our study shows that the taxon is clearly distinguished from auks in various skeletal features and can be confidently identified as a loon (Gaviiformes). Petralca resembles Colymboides in overall morphology of the wing bones, and clearly is a stem group representative of Gaviiformes. However, some features indicate that it is more closely related to the crown group taxon Gavia than to the stem group taxa Colymboides and Colymbiculus. Unusually thick bone walls of the limb bones indicate well-developed diving capabilities for Petralca austriaca.  相似文献   

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