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1.
The origin and first diversification of mammals in the Upper Triassic remain poorly understood, in part because many fossil discoveries are not fully studied, and in part because the material remains poor. The Saint-Nicolas-de-Port quarry (Rhaetian, France) is the second most important locality that yielded remains of Kuehneotherium, after the fissure-fillings of the Glamorganshire (Lower Jurassic, Wales). This study identifies one new species of Kuehneotherium, K. stanislavi, sp. nov., and a new genus of Kuehneotheriidae, Fluctuodon necmergor, gen. et sp. nov. For these two new species, lower and upper molars are described and the first reconstructions of the postcanine row are proposed. Comparisons with material of Kuehneotherium from other Upper Triassic sites (Syren in Luxembourg, Emborough in England, and Jameson Land in Greenland) suggest two distinct Upper Triassic specific kuehneotheriid assemblages, respectively, west and east of the London Brabant Massif. They also suggest that the extinction event during the Triassic/Jurassic transition did not have a great impact on Kuehneotherium.  相似文献   

2.
Summary Two characteristic new species and one new genus are described from the Late Triassic of Idaho (Wallowa Terrane):Brochidiella idahoensis n. gen., n. sp. andPtychostoma ornata n. sp.Brochidiella is only known from western North America.Ptychostoma is present in the Carnian of the European Alps (Tethys) and is widespread in the western part of the North American continent (Panthalassa). Late Triassic gastropod faunas from the accreted terranes of North America are poorly known but hold a great potential for future palaeobiogeographic reconstructions.  相似文献   

3.
We describe Triassic Crustacean microcoprolites from the western Tethyan realm (Lienz Dolomites, Southern Alps) and from the western shores of Gondwana (upper Magdalena valley, Colombia, South America). The Colombian fauna originates from the Norian Payandé Formation and represents the first discovery of microfossils in this formation. The Colombian fauna is highly diverse and shows close affinities to faunas of the western Tethyan and Mediterranean region but also to North American faunas. The form speciesPalaxius colombiensis andPalaxius groesseri are new, and forPalaxitts shastaensis the genusPayandea n. gen. is erected.Thoronetia quinaria is revised. It is shown, that crustacean microcoprolites are a good tool for supra-regional stratigraphic correlation. Possible migration paths are discussed.  相似文献   

4.
About 1400 otoliths were collected from a section of the Mandrikovka Beds (Priabonian) from Dnepropetrovsk (Ukraine). In this collection 35 taxa have been determined, four of them are new:Hemirhamphus sosimovichi n. sp., “genus äff.Apogon” ukrainicus n. sp.,Apogon bargi n. sp and “genus Percoideorum“andreevae n. sp. In the Mandrikovka associationApogon is the dominating genus. Together with some other warm-preferent genera the Apogonidae indicate warm water temperatures. On the other hand the common occurrence of cool-preferentRaniceps does not agree with this conclusion. The abnormal coexistence of these extremely different groups indicate a very complex hydrographical Situation during Sedimentation of the Mandrikovka beds which will be discussed. In comparison to western European Paleogene faunas the Mandrikovka association is very closely related to Late Eocene (Priabonian) faunas whereas relations to Early Oligocene faunas of the North Sea Basin remain on a markedly lower level.  相似文献   

5.
Nanogomphodon wildi n. gen., n. sp. is based on a tiny lower postcanine tooth from the lower Lettenkeuper (Lower Keuper or Erfurt Formation; Ladinian) of Michelbach an der Bilz (Baden-Württemberg). It represents the first record of a traversodont cynodont from the Middle Triassic of Europe and exhibits a distinctive combination of dental features. Along with recent discoveries of other traversodont taxa from the Upper Triassic of eastern North America,Nanogomphodon indicates the existence of a distinct lineage of these cynodonts in the Northern Hemisphere.   相似文献   

6.
Rhaetian fossil vertebrate faunas of Britain represent rich but biased samples of taxonomic diversity during uppermost Triassic time. Review of the Westbury Formation, Penarth Group, in particular, reveals a combination of marine, littoral, and terrestrial elements. Minimally, six species of shark are preserved along with a myriacanthid holocephalan, at least four actinopterygian taxa, a characteristic lungfish, ichthyosaurs, plesiosaurs, dinosaurs, and potentially the earliest representative of the Choristodera. Rare mammalian occurrences in the Westbury beds are also possible. Severnichthys gen. nov. is a large osteichthyan, probably a palaeonisciform chondrostean, which historically has been mistaken for a labyrinthodont amphibian. At least two additional actinopterygian species and a holocephalan are known from die Lilstock Formation, and a mammal or mammallike reptile is recorded from the uppermost Blue Anchor Formation. Analysis of element abundance in the disarticulated Westbury Formation assemblage indicates that many parts of some taxa are never preserved while other elements of the same form are common. Such preservational bias suggests that many species may be missing entirely from this long-studied but poorly understood taphocoenosis. Possibly contemporaneous cave faunas from nearby upland areas give a similarly biased picture of the terrestrial fauna during this time of widespread marine transgression.  相似文献   

7.
The enigmatic fissure deposits of south‐western England and southern Wales are famous for their unique assemblage of Late Triassic vertebrates, although their age is contentious. While recent studies of palynomorphs have dated some as Rhaetian, their conchostracan (Crustacea, Branchiopoda) assemblages have not been described in detail nor used in biostratigraphy. We find that species determination of British Late Triassic conchostracans requires detailed observations of size, shape and ornamentation. We provide evidence that although Euestheria brodieana is invariably smaller than E. minuta, with some slight differences in carapace ornamentation, the traditional view that they are very similar is upheld. The use of conchostracans as a biostratigraphical tool is here tested by application to the British Triassic fissures at Cromhall quarry where the usual stratigraphical evidence provided by superposition is absent. We find no distinction between conchostracans from bedded Rhaetian deposits of the UK and specimens collected from the fissure deposits of Cromhall Quarry, Gloucestershire, supporting a late Rhaetian age for these deposits.  相似文献   

8.
The present paper provides a palynological analysis of samples from the “Kössener Schichten”, “Schattwalder Schichten” and the ammonoid (Psiloceras planorbe)-bearing beds of the “Fleckenmergel/Fleckenkalk” found in the vicinity of Salzburg (Austria and adjacent part of Germany).It is shown that the compositional development of latest Triassic—earliest Jurassic palynological assemblages from Alpine sequences matches the situation in the Germanic realm. A characteristic phase in this development is interpreted in terms of the Rhaetipollis germanicus Assemblage Zone. It is considered that this zone could well be regarded as a palynological characterization of the Rhaetian Stage in Europe and North America.Although palynology does not support the Rhaetian concept based on the occurrence of the species Choristoceras marshi exclusively, the traditional ammonoid-based Triassic—Jurassic boundary can be palynologically recognized.  相似文献   

9.
Two new bryozoan species of the trepostome family Dyscritellidae,Dyscritellopsis thaynesianus n. sp. andDyscritellopsis montelloensis n. sp., are described from the Early Triassic (Smithian/Spathian) Thaynes Limestone, Nevada (USA). The bryozoan fauna documents the survival of Paleozoic lineages into the earliest Triassic on northern open shelves outside the tropics. The fauna holds paleobiogeo-graphic connections to the Early Triassic bryozoan faunas of Spitsbergen.   相似文献   

10.
A new dasycladacean alga,Pentaporella rhaetica n. g. n. sp., is described from the “Upper Rhaetian“ or “Rhaetoliassic“ Reef Limestones of Gruber-reef (Hintersee/Salzburg).  相似文献   

11.
Abstract:  Species of marine bivalves of the pectinoid genus Monotis provide useful biochronologic indices for the Late Triassic (middle Norian–earliest Rhaetian). We report the succession of Monotis at Hernstein in Lower Austria where typical late Norian Monotis salinaria (Schlotheim) are overlain by strata with apparently the youngest Monotis known of demonstrable Rhaetian age: Monotis hoernesi Kittl and Monotis rhaetica sp. nov., a species closely related to M. rudis Gemmellaro. A Rhaetian (Sevatian 2) age is confirmed by the co-occurrence of Monotis with the platform conodont Misikella posthernsteini and close association with the ammonoid Paracochloceras . A review of late Norian monotid species indicates that a profound extinction event occurred in the pelagic realm at or close to the Norian/Rhaetian boundary where c. 15 monotids ( Monotis s.l . and Maorimonotis ) became extinct. The surviving Monotis are dwarfed when compared to their Norian predecessors and may represent an ecological/phylogenetic response to the crisis.  相似文献   

12.
Shark teeth and an ornithischian dinosaur tooth are described from a new palynologically dated Rhaetian locality at Lons-le-Saunier (Jura, France). The structure of the enameloid of the teeth ofSynechodus rhaeticus has been studied, but this appears quite different from the usual pattern seen in neoselachian sharks, making the precise relationships of this species difficult to determine. On the other hand,‘Hybodus’ minor, which has long be thought to be a hybodont shark, is included among the Synechodontiformes. The find of the tooth of an ornithischian dinosaur is also reported. Study of the Lonsle-Saunier site seems to indicate a change in the marine faunas during the Rhaetian transgression, preferentially affecting the neoselachian sharks, which increase in abundance, and thedurophasous bony fishes, which become dominated bySareodon tomicus.  相似文献   

13.
Summary Six gastropod species from the Late Triassic Nayband Formation are reported. The following taxa are introduced as new:Trochonodus iranicus n. gen., n. sp. andCryptaulax convexa n. sp. The following species are transferred toTrochonodus n. gen.:Riselloidea aliabadensis Nützel and Senowbari-Daryan 1999 (type species ofTrochonodus),Riselloidea biarmata (Münster),Riselloidea bitorquata (Hébert and Eudes-Deslongchamps),Scalaria limatula Ammon, andAmberleya trimonilis (Orbigny). The holotype ofChulitnacula jenningsi (Douglas) is newly illustrated and described. According to the current state of knowledge, the gastropod faunas of the Nayband Formation near Esfahan and near Tabas differ considerably from each other. They share onlyAnulifera binodosa. TheAnulifera species-cluster has representatives in the Norian/Rhaetian from the North Alps, Iran, Burma, and South China. Contribution to the Triassic Paleontology of Iran No. 10. For No. 9 see previous text in this volume.  相似文献   

14.
15.
The new crustacean microcoprolite Halorina cryptica nov. ichnogen., nov. ichnosp., is reported from cryptic cavities cutting the Upper Triassic (Carnian to lower Rhaetian) Dachstein-type limestones from the Northern Apuseni Mountains, Romania. The new ichnotaxon is extremely abundant in cavities, neptunian dikes and sills filled with red ferruginous carbonate sediment. The associated microfauna consists of ostracods and rare foraminifera. The microfacies is represented by bioclastic coprolite-bearing wackestone-packstone to grainstone. The red ferruginous carbonate fillings are strongly bioturbated. The neptunian sill located at the top of the studied section contains a rich ichnofauna associated with brachiopod accumulations. It is dominated by the dimerelloid rhynchonellid Halorella, indicating a late Norian-early Rhaetian age. Although neptunian dikes and sills are rather common in the Dachstein-type carbonate platform that extended on the northwestern Tethyan margin, we report here the first record of mass-occurrence of crustacean microcoprolites in neptunian dikes and sills filled with red carbonate sediments of marine origin. They are interpreted here as cryptic cavities with specific palaeoenvironmental features (e.g., lack of light, abundant nutrients, intensive microbial activity) where crustacean arthropods thrived.  相似文献   

16.
17.
Two new gliding reptiles from the Late Permian Kul’chumovo-A locality (Orenburg Region), Rautiania alexandri gen. et sp. nov. and R. minichi sp. nov., are described and assigned to the family Weigeltisauridae. These finds substantially expand the knowledge of the morphology of this group and suggest the climax state of terrestrial tetrapod communities of eastern Europe in the pre-Triassic Time, which resulted in the development of ecological niches not typical of earlier terrestrial vertebrate faunas.  相似文献   

18.
New Late Triassic–earliest Jurassic magneto-biostratigraphic data have been obtained from three overlapping sections in the Southern Alps, Italy (Costa Imagna, Brumano, Italcementi Quarry), composed of ~ 520 m of shallow-marine carbonates outcropping in stratigraphic continuity. Characteristic magnetic components of presumed depositional age record a sequence of 9 normal and reverse polarity magnetozones (as defined by at least three stratigraphically superposed samples) linked by conodont and palynofloral evidence from this study and the literature to Rhaetian to Triassic–Jurassic boundary age. This represents a significantly larger number of polarity zones than previously recognized in more condensed Rhaetian sections from the literature, and by inference represents more time. These data are placed in a broader Late Triassic temporal framework by means of correlations to published magneto-biostratigraphic data from the Tethyan marine Pizzo Mondello section and the Newark astronomical polarity time scale (APTS). This framework is consistent with a position of the Norian–Rhaetian boundary (as defined at Brumano and Pizzo Mondello by the first appearance of Misikella posthernsteini) within Newark magnetozones E17r–E19r in the ~ 207–210 Ma time interval, in basic agreement with the position originally estimated in the Newark using pollen biostratigraphy (E18 at 208–209 Ma). This framework is also consistent with the position of the Triassic–Jurassic boundary interval (placed at Italcementi Quarry at the acme of Kraeuselisporites reissingeri coincident with a negative carbon isotope excursion) correlative to just above Newark magnetozone E23r and just below the oldest CAMP lavas dated at ~ 202 Ma. Hence, we estimate the duration of the Rhaetian to be ~ 5.5–8.5 Myr (or even longer if the Triassic–Jurassic boundary is instead placed above the negative carbon isotope excursion as at Kuhjoch, which is the designated GSSP for the base of the Hettangian), and encompassing 9 magnetozones. This duration contrasts with a duration of ~ 2 Myr and only ~ 4 magnetozones in several alternative published magneto-biostratigraphic schemes.  相似文献   

19.
The Albian sediments of the Transdanubian Range in Hungary were deposited in non-marine to fully-marine environments. The studied sections revealed diverse benthic ostracod faunas with moderately-preserved specimens. Forty-six taxa are identified and Cypridea zalanyii n. sp. is newly described. The detailed palaeoecological study of these ostracod faunas provided an opportunity to distinguish eight assemblages. The assemblages include limnic, brackish lagoon, shallow marine, reef and low oxygenated semi-enclosed basin environments in the Northern Tethys region we investigated. This work contributes to the knowledge about Albian non-marine faunas from Europe and explores ecological requirements of brackish faunas.  相似文献   

20.
A subrosion pipe or sinkhole is a geologic phenomenon that occurs due to dissolution of strata in the subsurface causing the overlying sediments to collapse. The subrosion pipe in the Winterswijk quarry complex in the eastern Netherlands yielded rare, dark-colored shales. Bivalves and palynomorphs indicate that the shales were deposited during the Rhaetian (uppermost Triassic). In addition, detailed correlation with other NW European localities in Great Britain, Austria, and Germany further constrained the age of the shales to the middle of the Rhaetian. The shales were deposited in a near-coastal environment and contained a low diverse macroinvertebrate fauna with bivalves and some brittle stars that lived in a hostile environment, probably caused by low salinity and oxygen levels. These middle Rhaetian shales were mixed with dark-colored middle to late Hettangian sediments, both overlying Middle Triassic (Anisian) strata, which is present in the pipe as well. The presence of Rhaetian sediments in the subrosion pipe reopened the discussion on its age of formation. We suggest that a collapse in the Middle Eocene is most likely. This research expands the knowledge of the marine realms in the uppermost Triassic in Europe, just prior to the Permian–Triassic extinction event.  相似文献   

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