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1.
Ostracodes Healdianella splendida Belousova, Paraparchites ganelini sp. nov., Paraparchites? hivachensis sp. nov. and Arcibairdia vodopadniensis sp. nov. are described from the Upper Permian deposits of the Khivach Formation (Kolyma-Omolon Basin, Eastern Siberia). Paraparchites species most closely resemble ancient Paleozoic ostracodes of the Boreal province. Valve morphology of Healdianella and Acribairdia points to their similarity to ostracodes from the upper levels of the Upper Permian of the Tethyan realm.  相似文献   

2.
A problematic organism, Bowengriphus perphlegis gen. et sp. nov., is described based on two specimens from the Late Permian Rangal Coal Measures of eastern central Queensland. It displays a double-looped feeding apparatus bearing small conical elements, considered homologous with that of the supposed lophophorate Odontogriphus omalus Conway Morris, 1976, from the Middle Cambrian Burgess Shale of British Columbia, Canada. Odontogriphids are thus interpreted as a group that survived through the Palaeozoic and made the transition from marine to freshwater environments. Recent proposals that odontogriphids are stem-group chordates are not well established.  相似文献   

3.
ABSTRACT. The earliest known Odonatoptera: Protozygoptera from the Upper Permian of Lodève (France) are described. Epilestes gallica sp. nov. belongs to the Permolestidae and Lodevia longialata gen. et sp. nov. to the Permepallagidae. Both of these families were previously known from the Kazanian of Russia, suggesting a similar age for the formation of Lodève.  相似文献   

4.
Exceptionally well-preserved specimens of Mizzia yabei (Karpinsky) were discovered in bituminous packstone intercalations of the early Upper Permian Maokou Formation of Anxian County (Sichuan, China). Staining techniques and x-ray diffraction reveal that the organic encrustation around the central stem and the lateral branches consists of aragonite. Average aragonite contents range between 27% and 40%. The bulk of the remaining 60–73% calcite represents cement. The total Sr-content is 3, 400 ppm, indicating 8,000–10,000 ppm for the aragonite fraction. The organically precipitated aragonite was deposited as closely packed fibres, 10–20 μm long and 0.5–1 μm wide. The fibres are arranged in clinogonal (water-jet) fascicles, which diverge towards the central (spar-filled) stem. This microstructure shows that the mineralization of the mucilage started at the periphery of the extracellular encrustation and progressed toward its interior. Diagenetic alterations of the original aragonite include various stages of breakdown of the fibres into 0.5–1 μm large granules (micritization), minor syntaxial growth of the fibres and local transformation of acicular aragonite into neomorphic calcite. The dasycladaleans from the Permian of Sichuan appear to be by far the oldest representatives of this order with preserved aragonitic mineralogy and microstructure. Comparably well-preserved examples are only known from Eocene and younger deposits.  相似文献   

5.
The skull of a small anomodont therapsid, from the Tapinocephalus Assemblage Zone (Abrahamskraal Formation, Beaufort Group, Upper Permian) in Northern Cape Province, South Africa, represents a new basal dicynodont and is described in detail. Colobodectes cluveri gen. et sp. nov. is distinguished from other dicynodonts by an anteroposteriorly extensive caniniform process, parietals that were broadly overlapped posterolaterally by posterodorsal processes of the postorbitals, diverging anterior palatal ridges, and a dorsoventrally low foramen magnum. A phylogenetic analysis indicates that Colobodectes is the basalmost member of a dicynodont clade that excludes Eodicynodon . This position is not particularly strong, as two additional steps are needed to make Colobodectes and Eodicynodon oosthuizeni exchange places on the most parsimonious tree. Another discovery of the phylogenetic analysis is that there is little basis for recognizing Eodicynodon oelofseni as the closest relative of E. oosthuizeni . The former species is identified as the sister taxon of a clade that includes the latter and all other dicynodonts.  相似文献   

6.
RAYNER, R. J., 1992. The Upper Permian articulate Phyllotheca australis from South Africa. The taxonomic position of two fossil articulates, which form an important element of the Permian Gondwana flora, is examined in the light of recent collections from South Africa. Vegetative and fertile axes, dispersed and attached sporangia, in-situ spores, isolated and attached whorls of leaves, rhizomes bearing roots and branches, naked axes and a permineralized axis are all assigned to Phyllotheca australis. The large numbers of axes with attached sporangia allow a reinterpretation of the fertile structure and the specific diagnosis is emended. Although it is recognized that the fossils assigned to this taxon may represent a species complex, there exist no clear morphological discontinuities between the material previously assigned to P. australis and P. indica from widely separated Gondwanan localities. Phyllotheca australis was common throughout Gondwana, and is a reliable index fossil of the Upper Permian.  相似文献   

7.
The gliding reptiles of the Upper Permian   总被引:1,自引:0,他引:1  
The skeleton of a long-ribbed reptile from the Upper Permian Marl Slate of north-east England is described. The animal is assigned to the genus Weigeltisaurus , previously recorded from the Kupferschiefer of West Germany. Long-ribbed reptiles from the Upper Permian of Madagascar are also considered. Daedalosaurus Carroll, 1978 is a junior synonym of Coelurosauravus Piveteau, 1926. The European and Madagascan genera can be accommodated within a single family Coelurosauravidae, Infraclass Eosuchia. The skull is diapsid with an incomplete lower temporal arcade. Comparison with the modern Draco and the Upper Triassic kuehneosaurids supports the conclusion that the coelurosauravids were effective gliders.  相似文献   

8.
Betulaceous leaves and fruits from the British Upper Palaeocene   总被引:2,自引:0,他引:2  
Fossil leaves and bracteate fruits are described from a new Upper Palaeocene locality in the Reading Beds near Newbury, southern England. The leaves are assigned to Craspedodromophyllum acutum Crane and correspond in many respects to those of living Betulaceae. The bracts and fruits are assigned to Palaeocarpinus laciniata Crane, which although referable to the Coryleae exhibits a novel combination of the characters of several living genera, particularly Corylus and Carpinus. An argument is presented for the association of these organs as a reconstructed fossil plant which is an extinct member of the Betulaceae. The evolution and fossil record of the Betulaceae are discussed, the late Upper Cretaceous and Palaeocene being regarded as the time at which the characters of modern genera were beginning to differentiate. Carpinus appears to have undergone a major Eurasian diversification during the late Palaeogene and early Neogene. Dispersal in Palaeocarpinus laciniata was probably less specialized than in most extant Coryleae.  相似文献   

9.
A New Basal Lystrosaurid Dicynodont from the Upper Permian of South Africa   总被引:1,自引:0,他引:1  
A new genus and species of late Permian dicynodont, Kwazulusaurus shakai , is described on the basis of a complete skull from the late Permian Dicynodon Assemblage Zone of the South African Beaufort Group. It is an advanced form which shows characters, such as the shape of the snout and the loss of the ectopterygoid, that link it to the early Triassic genus Lystrosaurus. Kwazulusaurus represents the most basal member of the lystrosaurian lineage. The phylogeny of progressive pristerodontian dicynodonts is discussed. It appears possible that the Kannemeyeriiformes and Lystrosauridae do not form a monophylum, as previously assumed. Instead a sister-group relationship between lystrosaurids and dicynodontids plus kannemeyeriiforms is suggested.  相似文献   

10.
Fossil leaves and bracteate fruits are described from a new Upper Palaeocene locality in the Reading Beds near Newbury, southern England. The leaves are assigned to Craspedodromophyllum acutum Crane and correspond in many respects to those of living Betulaceae. The bracts and fruits are assigned to Palaeocarpinus laciniata Crane, which although referable to the Coryleae exhibits a novel combination of the characters of several living genera, particularly Corylus and Carpinus. An argument is presented for the association of these organs as a reconstructed fossil plant which is an extinct member of the Betulaceae. The evolution and fossil record of the Betulaceae are discussed, the late Upper Cretaceous and Palaeocene being regarded as the time at which the characters of modern genera were beginning to differentiate. Carpinus appears to have undergone a major Eurasian diversification during the late Palaeogene and early Neogene. Dispersal in Palaeocarpinus laciniata was probably less specialized than in most extant Coryleae.  相似文献   

11.
Journal of Ichthyology - Data on the meristic, linear growth, and nutrition features of bleak Alburnus alburnus, recorded in the cooling pond of the Pechora State District Power Plant, are given....  相似文献   

12.
Late Permian terrestrial faunas of South Africa and Russia are dominated taxonomically and ecologically by therapsid synapsids. On the basis of a single specimen from the Upper Permian of South Africa, the varanopseid Elliotsmithia longiceps is the sole basal synapsid ('pelycosaur') known from Gondwana. Recent fieldwork in the Upper Permian of South Africa has produced a second varanopseid specimen that is referrable to Elliotsmithia . Data from both this specimen and the holotype suggest that Elliotsmithia forms a clade with Mycterosaurus from the Lower Permian of North America and Mesenosaurus from the Upper Permian of Eastern Europe. That postulate is supported by the three most parsimonious trees discovered in a new analysis of varanopseid phylogeny. However, the available data cannot resolve the interrelationships of these three genera. The new phylogenetic results contrast with earlier work identifying Elliotsmithia as the basal member of a clade that includes the North American taxa Aerosaurus , Varanops , and Varanodon . The new trees reduce the stratigraphic debt required by the latter scenario, and the one with the least stratigraphic debt identifies Elliotsmithia and Mesenosaurus as sister taxa. Two new taxa are erected, Mycterosaurinae and Varanodontinae, for the two varanopseid subclades.  相似文献   

13.
A Late Permian fauna of grylloblattid insects (Insecta; Grylloblattida) from the KwaZulu-Natal Province (South Africa) is considered. New taxa, Liomopterites ulterior sp. nov. and L. meridionalis sp. nov. (family Liomopteridae); Normandienoptera serotina gen. et sp. nov. and Afrogrylloblattus disputabilis gen. et sp. nov. (Skaliciidae), are described. Mioloptera stuckenbergi Riek, 1973 and Mioloptoides andrei Riek, 1976 of the family Liomopteridae are redescribed.  相似文献   

14.
The Pechora Region (PR) has extensive natural resources supporting forestry, oil and gas industries. The objective of this integrated study was to identify if local and long range pollution and biodiversity impacts were detectable on a regional scale using multi-indicators by selecting paired sites, close to industrial/forestry activities and in ‘reference’ areas (remote from any industrial centers, settlements or commercial activities). Chemistry of lichens, topsoil, lake water and sediments, plus diversity of lichens, birds and aquatic indicators along with landscape analysis were measured at eight sites in the PR to assess local impacts of oil/gas and forestry operations. Furthermore, an analysis of water and sediment chemistry was made at river stations and sites within the Pechora Delta. Local areas around industrial towns of Vorkuta and Usinsk showed increased pollution and decreased biodiversity. Among remote areas, subtle changes in pollution and biodiversity were detected close to oil/gas operations on the Kolva and Ortina Rivers, indicating early signs of environmental impact. Delta analyses showed limited impacts and most other sites remained unmodified reflecting low ecological impacts. Changes in forest landscape structure over large areas were apparently too small to cause significant negative impacts on bird diversity. This was the first attempt showing how multi-indicators can be used over broad spatial scales to assess environmental impacts in the PR.  相似文献   

15.
A new actinopterygian fish Yaomoshania minutosquama gen. & sp. nov., from the Upper Permian of the Dzungaria [Junggar] Basin in China is described. The material consists of two very fragmentary specimens showing almost exclusively scale rows. The arrangement of the scale rows of the holotype resembles the reversion lines of acanthodian caudal fins and of cheirolepids. The size and shape of the scales, and the diminishing size of the scales along the rows, is similar to those of acanthodians and those actinopterygians with small scales such as Cheirolepis. However, the histology of the scales demonstrates features that are found in more advanced actinopterygians: superimposed ganoine lamellae, the arrangement of dentine tubules and pulp canals, buried odontodes stacked on each other to make the ornamental ridges, and an asymmetric pattern of growth achieved by extensive remodelling (resorption and redeposition) of all layers of the scale. Yaomoshania minutosquama is proposed as a small-scale bearing, basal actinopterygian, different from Cheirolepis , but characterized by advanced histological characters.  相似文献   

16.
In terms of cumulative thickness and areal extent, the Khenifra Basin is one of the most important outcrops of Late Palaeozoic red-beds in central Morocco. Macro- and microfloral remains near the centre of the 1800 m-thick succession of interbedded conglomerates, sandstones, and mudstones are considered to be of middle to late Early Permian age. Here we give the first comprehensive analysis of the vertebrate ichnofossil record from the study area, based on 17 specimens of isolated footprints and incomplete step cycles collected at three localities that are lithostratigraphically equivalent to the plant-bearing horizons. The tetrapod ichnofauna comprises tracks of the plexus Batrachichnus Woodworth - Limnopus Marsh, Ichniotherium sphaerodactylum (Pabst), Dimetropus Romer and Price, and Dromopus Marsh which can be referred to temnospondyl, diadectomorph, synapsid (“pelycosaurian”) and early sauropsid trackmakers. This clearly Euramerican footprint assemblage, including the first occurrences of Ichniotherium and Dimetropus from outside Europe and North America, indicates a Late Carboniferous to Early Permian age of the fossiliferous strata. Judging from the relatively diverse ichnofauna and flora, the Khenifra Basin must have represented a well-established terrestrial ecosystem during that period. Its habitat could be specially important for the understanding of the phylogeny and dispersal of early tetrapods, inasmuch as we are able to report on an extremely rare type of diadectomorph footprint hitherto known only from the Early Permian of central Germany.  相似文献   

17.
A new dicynodont genus and species, Idelesaurus tataricus sp. nov. (Cryptodontidae), from the Semin Ovrag locality (Tatarstan, Tetyushinskii District; Upper Permian, Upper Tatarian Substage, Severodvinian Horizon) is described. The skull patterns of the East European and South African Cryptodontidae and Aulocephalodontidae are compared from the morphofunctional point of view.  相似文献   

18.
This paper contains a taxonomic study of the Permian tetrapod ichnofauna from the Carapacha Basin. Tetrapod traces are analyzed in their environmental context and compared with similar faunas from Europe and North America. This ichnofauna is particularly relevant because of the scarcity of Permian tetrapod tracks from South America and also of Permian tetrapod fossils from Argentina. Ephemeral fluvial and shallow lacustrine deposits compose the sedimentary succession of the basin, which is represented by the Carapacha Formation. Most of the tracks have been collected from the upper member of the formation (Urre-Lauquen Member), mainly from freshwater ephemeral lake deposits as well as from playa-lake mudflats. The deposits of this member have been attributed to the early Late Permian on the basis of a Glossopteris fossil flora. Ichnotaxonomic designations of tetrapod traces are made on the basis of morphologic features that reflect the anatomy of the producer and special attention has been paid to extramorphologic deformations observed in the track assemblage. A total of four footprint ichnotaxa have been recognized, namely Batrachichnus salamandroides (Geinitz, 1861 Geinitz, H. B. 1861. Dyas oder die Zechsteinformation und das Rhotliegende—Die animalischen Überreste der Dyas, 130 ppLeipzig: Wilhelm Engelmann.  [Google Scholar]), Hyloidichnus bifurcatus Gilmore, 1927 Gilmore, C. W. 1927. Fossil footprints from the Grand Canyon: second contribution. Smithsonian Miscellaneous Collection, 80(3): 178.  [Google Scholar], cf. Amphisauropus isp. and cf. Varanopus isp. These track taxa are associated with two forms of vertebrate swimming traces (Characichnos isp. and type A swimming trace) and a possible fish trail. Invertebrate trace fossils include abundant arthropod locomotion traces and Scoyenia isp. The ichnofauna is composed of six tetrapod ichnocoenoses that are dominated by tiny amphibian tracks attributed to Temnospondyli (Batrachichnus and type A swimming trace) and Seymouriamorpha (Amphisauropus), and also contain the footprints of small reptiles, mostly Captorhinomorpha and possibly Pelycosauria (Hyloidichnus and Varanopus). Even if the ichnofauna of the Carapacha Basin is slightly younger than typical examples from the literature of the Early Permian “red bed ichnofacies” (Hunt et al., 1995b Hunt, A. P., Lucas, S. G., Lockley, M. G., Haubold, H. and Braddy, S. 1995b. Tetrapod ichnofacies in Early Permian red beds of the American Southwest. Bulletin New Mexico Museum of Natural History and Science, 6: 295301. Early Permian footprint facies [Google Scholar]), a comparison is made. However, further detailed case studies are needed to formally define this “red bed ichnofacies” and its prospective subdivisions.  相似文献   

19.
Fabien Knoll 《Geobios》2009,42(6):755
The remains of an ornithopod dinosaur from the Upper Barremian (Lower Cretaceous) of Auxerre (Burgundy, France) are described. They consist of several vertebrae and a fragmentary scapula. Despite obvious morphological and dimensional affinities with the species Iguanodon bernissartensis, the state of the specimen does not allow any identification more precise than Iguanodontia indet. Reappraisal of the French Upper Barremian record of medium and large-sized ornithopods reveals that no specimen can be definitely determined to the specific level.  相似文献   

20.
Abstract: This study involves bryophyte fossils from the Teresina Formation (Permian–Guadalupian) collected in the Rio Preto Quarry in the state of Paraná, southern Brazil. Two new genera are proposed, with two new species: Capimirinus riopretensis sp. nov. and Yguajemanus yucapirus sp. nov. C. riopretensis sp. nov. included a lateral sporophyte that was organically attached to a gametophyte and is thus one of the oldest pleurocarpous fossils known today. This discovery provides clear evidence of the evolution of mosses during the Permian, because an acrocarpous moss from this period was also found in India. The preservation of such a fragile structure demonstrates that no prefossilization displacement took place and that the sediments accumulated in a low‐energy, fresh‐water environment, similar to a lake fed by rain, and isolated from the direct influence of the sea. Campimirinus riopretensis may be placed within the earlier pleurocarps, and Yguajemanus yucapirus sp. nov. may belong to the Bryalean families. However, we were not able to place neither of these species in any existing family today.  相似文献   

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