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1.
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A new chonetid genus and species, Kanokurachonetes kanokurensis (subfamily Rugosochonetinae, family Rugosochonetidae), from the Middle Permian (Wordian, Kanokura Formation) of the southern Kitakami Mountains (Northeast Japan) are described.  相似文献   

3.
Continental strata of Early and Middle Jurassic age are seldom-exposed, and little is known of the history of sauropod dinosaurs prior to the neosauropod radiation of the end of the Middle Jurassic. Here, we report, in the Middle Jurassic of the Occidental Saharan Atlas (Algerian High Atlas), the discovery of a skeleton, including cranial material, of a new cetiosaurid sauropod. Chebsaurus algeriensis n. g., n. sp. represents the most complete Algerian sauropod available to date, only few remains were found before. To cite this article: F. Mahammed et al., C. R. Palevol 4 (2005).  相似文献   

4.
The Permian and Triassic were key time intervals in the history of life on Earth. Both periods are marked by a series of biotic crises including the most catastrophic of such events, the end‐Permian mass extinction, which eventually led to a major turnover from typical Palaeozoic faunas and floras to those that are emblematic for the Mesozoic and Cenozoic. Here we review patterns in Permian–Triassic bony fishes, a group whose evolutionary dynamics are understudied. Based on data from primary literature, we analyse changes in their taxonomic diversity and body size (as a proxy for trophic position) and explore their response to Permian–Triassic events. Diversity and body size are investigated separately for different groups of Osteichthyes (Dipnoi, Actinistia, ‘Palaeopterygii’, ‘Subholostei’, Holostei, Teleosteomorpha), within the marine and freshwater realms and on a global scale (total diversity) as well as across palaeolatitudinal belts. Diversity is also measured for different palaeogeographical provinces. Our results suggest a general trend from low osteichthyan diversity in the Permian to higher levels in the Triassic. Diversity dynamics in the Permian are marked by a decline in freshwater taxa during the Cisuralian. An extinction event during the end‐Guadalupian crisis is not evident from our data, but ‘palaeopterygians’ experienced a significant body size increase across the Guadalupian–Lopingian boundary and these fishes upheld their position as large, top predators from the Late Permian to the Late Triassic. Elevated turnover rates are documented at the Permian–Triassic boundary, and two distinct diversification events are noted in the wake of this biotic crisis, a first one during the Early Triassic (dipnoans, actinistians, ‘palaeopterygians’, ‘subholosteans’) and a second one during the Middle Triassic (‘subholosteans’, neopterygians). The origination of new, small taxa predominantly among these groups during the Middle Triassic event caused a significant reduction in osteichthyan body size. Neopterygii, the clade that encompasses the vast majority of extant fishes, underwent another diversification phase in the Late Triassic. The Triassic radiation of Osteichthyes, predominantly of Actinopterygii, which only occurred after severe extinctions among Chondrichthyes during the Middle–Late Permian, resulted in a profound change within global fish communities, from chondrichthyan‐rich faunas of the Permo‐Carboniferous to typical Mesozoic and Cenozoic associations dominated by actinopterygians. This turnover was not sudden but followed a stepwise pattern, with leaps during extinction events.  相似文献   

5.
Shallow-marine limestones associated to a Palaeotethyan seamount in the Teke Dere unit of the Tavas Nappe (Lycian Nappes, SW Turkey) are essentially latest Moscovian-Kasimovian in age. The wide range of microfauna and -flora of the series show biogeographic affinities comparable to those from the northern Palaeotethyan borders (especially to assemblages from the Carnic Alps, Urals, Donbass and Darvaz). These biogeographic affinities seem to persist until the end of the Early Permian (Artinskian). The Middle Permian fauna is represented by the typical warm, tropical assemblages known at the same time in the Palaeotethys (NW Caucasus, Darvaz, south China, Primorie and Japan), and in the Neotethys (Transcaucasia, central Iran, southern Afghanistan and Sibumasu). The new Kasimovian algae and incertae sedis Novantiellopsis elliottii n. gen. n. sp., Uvanellopsis fluegelii n. gen. n. sp., Tubiphytes rauzerae n. sp. and Asselodiscus davydovi n. sp. are described.  相似文献   

6.
A new scanilepiform, Beishanichthys brevicaudalis gen. et sp. nov. , is named and described based on fossils from the Lower Triassic lake deposits exposed in Beishan area, Gansu Province, China. The discovery documents a new record of this group, which is significantly older than other known scanilepiforms from China, and is slightly younger than Evenkia from the Lowest Triassic of Central Siberia. Although the Beishan beds were previously interpreted as Late Permian in age, based on megaplant fossils, this new discovery supports the reinterpretation of the deposits as Early Triassic in age, based on vertebrate fossils from the same locality and horizon. Phylogenetic analysis was conducted to resolve the relationships of Scanilepiformes with other actinopterygian clades, and the inter‐relationships within Scanilepiformes. Contrary to previous thought that scanilepiforms are closely related to the Amiidae, the phylogenetic results of this study recognize the Scanilepiformes as stem‐group neopterygians. Relationships of the Scanilepiformes and Australosomus with other neopterygians remain unresolved. With a characteristic long‐based dorsal fin, scanilepiforms represent a small group that emerged in Early Triassic freshwater environments, inhabited Eurasia and North America during the Middle–Late Triassic, briefly invaded the marine environment by the Late Triassic in Europe, and became extinct at the end of Triassic. © 2011 The Linnean Society of London, Zoological Journal of the Linnean Society, 2011, 161 , 595–612.  相似文献   

7.
New orthopteran Crinoedischia lapeyriei sp. nov. is described and illustrated from the Middle Permian (Guadalupian) of Lodève Basin in southern France. The new species is separated from the Lower Permian (Artinskian) Crinoedischia species by differences in wing venation pattern such as long ScP with anterior branches, RA with prominent distal branches, and MA ending with three branches. The significance and parallels of entomofaunas between Salagou and Wellington formations (Lodève, Elmo, Midco) are briefly discussed.  相似文献   

8.
A study of both silicified and nonsilicified specimens of Permian reticularioid brachiopods from South China suggests thatPermophricodothyris, a genus previously rarely reported from China, is actually very common and abundant in the Middle and especially Upper Permian of South China. This study also clarifies, for the first time, that many of the reticularioid brachiopod species previously described asSquamularia in fact belong toPermophricodothyris. The new data presented in this paper also allows a critical evaluation ofPermophricodothyris in relation to its closest allies:Phricodothyris, Squamularia, Bullarina andNeophricodothyris. The revision reveals that a total of 18Permophricodothyris species are present in the Middle and Upper Permian of South China, with only one species,P. squamularioides, having survived the Permian-Triassic mass extinction. Two species,P. grandis (Chao) andP. guangxiensis Han, Zhou & Wang, are redescribed here, providing critical new information on the morphology and taxonomy of these species.  相似文献   

9.
Aristov DS  Storozhenko SY 《ZooKeys》2011,(130):111-130
A new replacement name Permulidaenom. n. is proposed for the Permian family Aliculidae Storozhenko, 1997 (Insecta: Grylloblattida). A review of Permulidae is given. All genera and species are redescribed and illustrated. A key to genera of Permulidae is given. New taxa of Permulidae are described: Permula edemskiisp. n., Sojanopermula rasnitsynisp. n., Kazanalicula reductagen. et sp. n., Mezenalicula connatagen. et sp. n., all from the Soyana locality (Middle Permian, Kazanian Stage; Arkhangelsk Region, Russia), and Mezenalicula conjunctasp. n. from the Isady locality (Upper Permian, Severodvinian Stage; Vologda Region, Russia). New combinations are proposed: Permula minor (Aristov, 2004), comb. n. for Sojanopermula minor Aristov, 2004; Permula tshekardensis (Aristov, 2004), comb. n. for Sojanopermula tshekardensis Aristov, 2004. A new genus Acropermulagen. n. (type species: Permula acra Kukalová, 1964, from the Lower Permian of Czech Republic) is established in the family Ideliidae. Neraphidia Novokshonov & Novokshonova, 1997 is transferred from Aliculidae to the order Eoblattida as a genus of uncertain taxonomic position inside this order.  相似文献   

10.
The Richards Spur Locality of Oklahoma, USA, long known for its highly diverse Early Permian terrestrial tetrapod assemblage, is particularly interesting for the presence of many endemic taxa. The parareptilian component of the assemblage, rare members of other Early Permian communities, is especially diverse at Richards Spur, consisting of six species. The newest parareptile, A byssomedon williamsi gen. et sp. nov. , consists of an articulated left jaw and various disarticulated cranial and postcranial elements. A new phylogenetic analysis of parareptiles, based on an updated modified data matrix revealed that Ab . williamsi is a member of the small clade Nyctiphruretidae. This makes Ab . williamsi the first and oldest nyctiphruretid, a clade of parareptiles otherwise known from the Middle and Late Permian of Russia, extending the age of the clade back into the Early Permian. This discovery also raises the possibility that nyctiphruretids may have dispersed from western Laurasia to eastern Laurasia. The characteristic jugal morphology of Ab . williamsi shows that it would have possessed a slender, deep, temporal emargination. The current topology of Parareptilia indicates that there was considerable variability in the patterns of lateral temporal openings amongst the various members of this clade, suggesting that there may have been multiple, independent modifications of this region of the skull. © 2014 The Linnean Society of London  相似文献   

11.
At the end of the Permian, numerous amphibians and therapsids vanished, creating many empty ecological niches, which were occupied by new creatures. This event brought new trends in animal locomotion thanks to modifications of the skeleton limbs. The newcomers were faster and more dangerous for other families. The prominent ichnogenera were Synaptichnium, Chirotherium, Brachychirotherium, Isochirotherium, and Sphingopus. Their trackmakers were Thecodonts, reptiles having the above-mentioned evolutive characteristics. Dinosaurs, which appeared at the end of the Triassic period, were likely their descendants, which raises the question of when and where the dinosaurs originated. The comparison of the trackways of the Middle and upper Triassic with those of the lower Jurassic leads to the conclusion that the two sets of tridactyl ichnites were similar and were made by the same group of trackmakers, the dinosaurs. We had many passionate discussions on this subject with Bill Sarjeant when studying the discoveries made in Europe the past 40 years.  相似文献   

12.
The trend of species diversity and spatiotemporal distribution of spherical radiolarians of the genus Entactinia Foreman, 1963 in the Permian Period is analyzed. The center of origin of Permian entactinians in the Cis-Ural Paleobasin is established in the area of the modern interfluve of the Ural River and latitudinal current of the Belaya River on the Southern Urals. It is shown that the species composition of this genus almost completely changed in certain Permian epochs. Two forefather species of each new pleiad of Early, Middle, and Late Permian are revealed: Entactinia parapycnoclada and E. tyrrelli. Two new species of the Lower Permian radiolarians from the Southern Urals and Northern Mugodzhary, E. chernykhi sp. nov. and E. subquadrata sp. nov., are described.  相似文献   

13.
14.
A new species, Neocalamites hunchunensis sp. nov. from the Upper Permian Jiefangcun Formation of northeastern China is described. The Jiefangcun Upper Permian Flora is briefly characterized. Its taxonomic composition, age, and significance for paleophytogeographical reconstructions are discussed. The Late Permian phase in equisetophyte evolution is considered.  相似文献   

15.
The main aim of this paper is to review Middle Permian through Middle Triassic continental successions in European. Secondly, areas of Middle–Late Permian sedimentation, the Permian–Triassic Boundary (PTB) and the onset of Triassic sedimentation at the scale of the westernmost peri-Tethyan domain are defined in order to construct palaeogeographic maps of the area and to discuss the impact of tectonics, climate and sediment supply on the preservation of continental sediment.At the scale of the western European peri-Tethyan basins, the Upper Permian is characterised by a general progradational pattern from playa-lake or floodplain to fluvial environments. In the northern Variscan Belt domain, areas of sedimentation were either isolated or connected to the large basin, which was occupied by the Zechstein Sea. In the southern Variscan Belt, during the Late Permian, either isolated endoreic basins occurred, with palaeocurrent directions indicating local sources, or basins underwent erosion and/or there was no deposition. These basins were not connected with the Tethys Ocean, which could be explained by a high border formed by Corsica–Sardinia palaeorelief and even parts of the Kabilia microplate. The palaeoflora and sedimentary environments suggest warm and semi-arid climatic conditions.At the scale of the whole study area, an unconformity (more or less angular) is observed almost everywhere between deposits of the Upper Permian and Triassic, except in the central part of the Germanic Basin. The sedimentation gap is more developed in the southern area where, in some basins, Upper Permian sediment does not occur. The large sedimentary supply, erosion and/or lack of deposition during the Late Permian, as well as the variable palaeocurrent direction pattern between the Middle–Late Permian and the Early Triassic indicate a period of relief rejuvenation during the Late Permian. During the Induan, all the intra-belt basins were under erosion and sediment was only preserved in the extra-belt domains (the northern and extreme southern domains). In the northern domain (the central part of the Germanic Basin), sediment was preserved under the same climatic conditions as during the latest Permian, whereas in the extreme southern domain, it was probably preserved in the Tethys Ocean, implying a large amount of detrital components entering the marine waters. Mesozoic sedimentation began in the early Olenekian; the ephemeral fluvial systems indicate arid climatic conditions during this period. Three distinct areas of sedimentation occur: a northern and southern domain, separated by an intra-belt domain. The latter accumulated sediments during the Early–Middle Permian and experienced erosion and/or no-deposition conditions between the Middle–Late Permian and the beginning of Mesozoic sedimentation, dated as Anisian to Hettangian. At the top of the Lower Triassic, another tectonically induced, more or less angular unconformity is observed: the Hardegsen unconformity, which is dated as intra-Spathian and is especially found in the North European basins. This tectonic activity created new source areas and a new fluvial style, with marine influences at the distal part of the systems. During the Anisian and Ladinian, continental sedimentation was characterised by a retrogradational trend. In other words, the fluvial system evolved into fluvio-marine environments, attesting to a direct influence of the Tethys Ocean in the southern and northern domains. Both at the end of the Olenekian (Spathian) and during the Anisian, the presence of palaeosols, micro- and macrofloras indicate less arid conditions throughout this domain.  相似文献   

16.
A collection of Cynodontia from the Permian of Eastern Europe is revised. The taxonomic position of a number of previously described forms is reconsidered. New taxa, Novocynodon kutorgai gen. et sp. nov. (Thrinaxodontidae) from the Middle Permian and Sludica bulanovi gen. et sp. nov. (Procynosuchidae) from the Upper Permian, are described.  相似文献   

17.
Y. Ezaki 《Palaeontology》2000,43(2):199-217
Scleractinian corals are the most important constituents of modern coralgal reefs. For many years, it was thought that they first appeared in the Middle Triassic and subsequently underwent explosive radiation. However, abundant scleractinian-like corals with ancestral morphological traits have recently been recovered from Middle Permian sponge reefs in China, which not only confirms a role in Permian reef ecology but also suggests a possible Palaeozoic origin for the group. Two species of a new Permian scleractiniamorph genus from China are described herein as Houchangocyathus wangi gen. et sp. nov. and Houchangocyathus yaoi gen. et sp. nov. Putative Palaeozoic Scleractinia may have evolved over a substantial time interval and diverged into stem lineages by the end of the Permian. These forms evolved within both the rigid framework of their basic body plan and the morphological constraints characteristic of each lineage. The Middle Permian development of calcisponge reefs was closely related to habitat expansion, which would have provided an ideal dwelling for scleractinian-like corals and enhanced their chances of fossilization. Such scleractiniamorphs disappeared at the end-Permian extinction, but may have survived as progenitors of Triassic Scleractinia.  相似文献   

18.
A small brachiopod fauna is described from the carbonate rocks of the basal Shazipo Formation of the Baoshan Block, western Yunnan, south-west China, including significant new ventral and dorsal internal morphological features of Cryptospirifer omeishanensis Huang. This fauna is regarded as Wordian (Middle Guadalupian, Middle Permian) because of the presence of Cryptospirifer omeishanensis Huang and associated fusulinids ( Neoschwagerina craticulifera Zone). Palaeobiogeographically, the brachiopod fauna is of considerable interest because of its admixed nature characterized by typical warm-water Cathaysian elements intermingled with temperate Peri-Gondwanan taxa. This in turn is interpreted to indicate that the Baoshan Block may have been situated in an intermediate palaeogeographical position between Gondwanaland to the south and Cathaysia to the north during the Mid Permian and, as such, it probably furnished an important 'stepping stone' for the dispersal of Mid Permian eastern Tethyan marine invertebrate taxa (e.g. Cryptospirifer ) to the western Tethys.  相似文献   

19.
Prokop J  Nel A 《ZooKeys》2011,(130):41-55
Three new palaeopteran insects are described from the Middle Permian (Guadalupian) of Salagou Formation in the Lodève Basin (South of France), viz. the diaphanopterodean Alexrasnitsyniidaefam. n., based on Alexrasnitsynia permianagen. etsp. n., the ParelmoidaePermelmoa magnificagen. etsp. n., and Lodevohymen lapeyrieigen. etsp. n. (in Megasecoptera or Diaphanopterodea, family undetermined). In addition the first record of mayflies attributed to family Syntonopteridae (Ephemeroptera) is reported. These new fossils clearly demonstrate that the present knowledge of the Permian insects remains very incomplete. They also confirm that the Lodève entomofauna was highly diverse providing links to other Permian localities and also rather unique, with several families still not recorded in other contemporaneous outcrops.  相似文献   

20.
The Palaeozoic–Mesozoic transition is characterized not only by the most massive Phanerozoic mass extinction at the end of the Permian period, but also its extensive aftermath and a prolonged period of major biotal recovery during the succeeding Middle to Late Triassic. Particularly, Anisian insect species from units of the Lower to Middle Muschelkalk from the Central European Basin are rare. The specimens described here originated from the Anisian Wellenkalk facies (Lower Muschelkalk), Vossenveld Formation of the Winterswijk quarry, The Netherlands, and from the orbicularis Member (lowermost Middle Muschelkalk, Anisian) of Esperstedt near Querfurt (Saxony-Anhalt). Thus, the described insect remains from Winterwijk and Esperstedt expand our knowledge about Middle Triassic terrestrial arthropod communities and their palaeodiversity. A new species of Chauliodites (C. esperstedti sp. nov) is introduced.  相似文献   

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