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Summary A rather diverse gastropod fauna from Sarmatian deposits of the Austrian/Hungarian Eisenstadt-Sopron Basin was studied. The fauna derives from two layers of clay and silt within a siliciclastic section at St. Margarethen in Burgenland (Austria). These layers are interpreted as littoral mudflats which formed during the Sarmatian (Late Middle Miocene) along the western coast of the Central Paratethys. Strong shifts in the composition of the gastropod fauna, dominated by Potamididae (Cenogastropoda: Cerithioidea), within each layer indicate successions of limnic-fluvial to oligohaline, brackish-littoral, and marine-littoral environments. These shifts in facies are reflected by an alternational of thePotamides hartbergensis assemblage,Granulolabium bicinctum assemblage, and thePotamides disjunctus assemblage. The speciesJujubinus turriculus (Eichwald, 1850),Gibbula buchi (Dubois, 1831), andCylichnina elongata (Eichwald, 1830) are reported for the first time from the Sarmatian of the Paratethys.Mitrella agenta nov. sp. (Neogastropoda: Columbellidae) is introduced as a new species. These species might represent relics of the diverse Badenian fauna but could also prove a minor ingression of marine species from an adjacent bioprovince in the Late SarmatianMactra “Zone”.  相似文献   

3.
Lower Callovian deposits (subpatruus and koenigi ammonite zones) in the Mikhailovskii Mine section (Central Russia, Kursk Region) yielded 13 ostracode species (two of them are new) belonging to ten genera. This ostracode assemblage corresponds to ostracode beds with Praeschuleridea wartae-Pleurocythere kurskensis. The stratigraphic range of these beds corresponds to three ammonite biohorizons: Chamoussetia crobyloides, Kepplerites gowerianus gowerianus, and K. indigestus. Three distinct ostracode assemblages have been defined in the section based on their taxonomy and occurrence pattern. Two new species, Pleurocythere kurskensis sp. nov. and Pseudohutsonia wienholzae sp. nov., are described.  相似文献   

4.
New bryozoans from the Middle Callovian (Middle Jurassic) of Moscow city (Reptomulticava pileola sp. nov.) and the Moscow Region (Spirodella radiolobata gen. et sp. nov.) and from the Middle Oxfordian (Upper Jurassic) of the Kostroma Region (Hyporosopora mittai sp. nov.) are described. All three bryozoans belong to the class Stenolaemata. Some features of their colonial organization and environmental conditions are discussed.  相似文献   

5.
Abstract: Peloneustes philarchus is the most abundant pliosaurid from the Peterborough Member of the Oxford Clay Formation (Callovian) of the UK. It is a valid taxon possessing a unique character combination, including a single autapomorphy: the interdentary symphysis is raised dorsally on a narrow platform. Twenty‐one specimens can be positively referred to P. philarchus. However, other specimens previously referred to Peloneustes, from the Peterborough Member near Peterborough, and the lower Oxfordian strata of Marquise, northern France, represent distinct, unnamed taxa. The skull of P. philarchus is described in detail, including new information from an uncrushed, three‐dimensionally preserved specimen and a specimen with a well‐preserved palate. Well‐preserved material clearly indicates that P. philarchus lacked nasals, but possessed a lacrimal. A previously unrecognised ‘palpebral’ forms part of the dorsal orbit margin adjacent to the prefrontal. The number of maxillary (30–31) and dentary (36–44) alveoli, the number of dentary alveoli adjacent to the mandibular symphysis (13–15), the number of foramina on the frontal and jugal, the breadth of the parasphenoid, breadth of the anterior (narial) process of the palatine and the presence of a lappet of the angular that extends onto the posterodorsal surface of the retroarticular process vary among individuals but are not considered sufficient to justify the recognition of new taxa. The presence of an open palpebral–prefrontal suture, the size of the ventral midline tubercle of the basioccipital and the presence of an anterior interpterygoid vacuity seem to vary with body size.  相似文献   

6.
Gastropod faunas from the Early Jurassic (Late Pliensbachian–Early Toarcian) marine deposits of Chubut Province, Argentina, are described from Lomas Occidentales, Cerro La Trampa and Puesto Currumil localities, representing eight species, three of them new. These are Scurriopsis? sp., Chartronella gradata sp. nov., Calliotropis? sp., Pleurotomaria sp., Leptomaria sp., Hamusina? wahnishae sp. nov., Colpomphalus musacchioi sp. nov. and Jurassiphorus? cf. triadicus Haas. The gastropod assemblage reported here testifies paleobiogeographical connections with other coeval gastropod associations from the western Tethys. However, Chartronella, Hamusina and Jurassiphorus may represent survivors of Triassic associations, considering the ancient seaway from Peru as the most plausible hypothesis for biotic exchange of these faunas during the Late Triassic–Early Jurassic boundary. An abundant and diverse invertebrate fauna such as corals, echinoderms, cephalopods, brachiopods, bivalves and other gastropods found in association with the gastropods described here characterises a shallow marine environment for the gastropod-bearing rocks.http://www.zoobank.org/urn:lsid:zoobank.org:pub:7B8EAFC0-3AC0-4F91-97A5-22AAC6A19909  相似文献   

7.
Summary The Sikhor Formation (new) is a predominantly siliciclastic sediment package intercalated between the marly-silty Baghamshah Formation (below) and the calcareous Esfandiar Limestone and Qal'eh Dokhtar Limestone formations (above). All stratigraphic evidence points to an Early Callovian age of the formation. The Sikhor Formation is restricted to the southern and central Shotori Mountains and consists of two members: The Kuh-e-Neygu Member (new) is composed of fluvialdeltaic conglomerates, sandstones, and siltstones grading into marly silt of the Baghamshah Formation. The overlying Majd Member (new) is characterised by mixed siliciclastic-carbonate sediments that record the interfingering of carbonate ramp sediments with fluvialdeltaic sands and silts. Evidence of erosional truncation of the underlying Baghamshah Formation and confinement of the siliciclastic sediment to a comparatively narrow, NNW-SSE elongated strip suggest that the formation had its origin in the asymmetric uplift of a westdipping tilted fault block in the southern Shotori Mountains that shed its sediment predominantly in a northern and eastern direction. After erosional levelling, the former uplifted areas were overgrown by the highly productive Esfandiar Carbonate Platform. The Sikhor Formation thus is evidence of an extensional tectonic pulse in the early Callovian and underlines that this area of the Tabas Block was a tectonically highly unstable area during most of the Jurassic.  相似文献   

8.
Two new species of encrusting bryozoans (Stenolaemata, Tubuliporida) from the Middle Callovian (Middle Jurassic) deposits of the Bryansk Region, Oncousoecia guzhovi sp. nov. and Microeciella fokinensis sp. nov., are described. Their intracolonial variability, which is due to differences in astogenetic stages and to external factors, is discussed.  相似文献   

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Brachiopods of the order Orthida from the Lower and Middle Devonian of northeastern Russia: Skenidium diversus Baranov (family Skenidiidae); Datnia gen. nov., with the type species D. asiatica sp. nov. (subfamily Prokopiinae); Janzhinshinia gen. nov., with the type species J. datnensis sp. nov. (subfamily Isorthinae); Cortezorthis chobotchalensis (Alekseeva) (subfamily Cortezorthinae); Elenia gen. nov., with the type species E. gerensis sp. nov. (family Dicoelosiidae); Seimtchania communis (family Seimtchaniidae); Simakovia gen. nov., with the type species S. rara sp. nov. (family Draboviidae); Schizophoria distenta sp. nov., S. grande Baranov, S. striatula (Schlotheim) (family Schizophoriinae); and Hypsomionia sinsera Baranov (family Hypsomioniidae) are described.  相似文献   

11.
The genus Eckhardites Mitta 1999, with the type species Macrocephalites pavlowi Smorodina, 1928 is discussed and its diagnosis and assignment to the family Cardioceratidae are substantiated. Eckhardites is compared to the genus Macrocephalites Zittel (family Sphaeroceratidae), to which some workers presently assign the type species of Eckhardites. Three species of Eckhardites are recorded from the basal Callovian elatmae Zone of the Russian Platform, one of which (E. menzeli (Mönnig)) was originally described from the synchronous beds in Germany. A new species E. dietli sp. nov. is described.  相似文献   

12.
A dinosaur vertebra found in the course of road works in the “Chevain Marls” (marine Callovian) of the Vermont outlier, near the village of Béthon (Sarthe, Pays-de-la-Loire, western France) is described and referred to a stegosaur (cf. Lexovisaurus). It is the first record of a dinosaur in the Middle Jurassic of that area. The specimen was probably derived from the floating carcass of an animal that had lived on the emerged areas of the Armorican Massif, near which the Chevain Marls were deposited. This fossil is an addition to the short list of stegosaur remains reported from France.  相似文献   

13.
The history of research in Oligocene paleozoology of Central Kazakhstan is described. Continental Oligocene strata may be recognized on the basis of different Oligocene fossil vertebrates, taking into account the stratigraphic occurrence of mammal genera and species, their belonging to subdivisions of the General Stratigraphic Scale as well as statistical determination of assemblage formation time. At least two stratigraphic levels occur in this region. These are: Saryin (Myneskesuyek, Mogila Saty localities), the lower part of Chelkarnura (Shintuzsay) Svitas (upper half of the Lower Oligocene—Upper Oligocene); and the upper part of Chelkarnura (Chelkar‐Teniz) and Betpakdala (Kyzyl‐Kak) Svitas (Upper Oligocene). Apparently the Chelkar‐Teniz vertebrate assemblage originated in several stages. They require future studies of stratigraphic position of fossils.

Origin and ways of migration of mammalian genera from the Oligocene faunistic assemblages of Central Kazakhstan are discussed.

A preliminary paleoecological study suggests that animals of open and rarefied landscapes dominated in the Myneskesuyek region, the faunistic assemblage of which appears to have been the most ancient. Vertebrate inhabitants of partly open and open, as well as forest habitats probably were present in Chelkar‐Teniz. Animals primarily of forest and scattered woodland dwellers predominated in the Kyzyl‐Kak locality.  相似文献   

14.
Ecological patterns of mollusc assemblages and vegetation in relation to water chemistry, water regime, nutrient availability and climate were studied in eastern Polish lowland fens. Our goal was to examine if major compositional changes differ for molluscs and vegetation under the joint influence of multiple ecological gradients. Altogether 32 fen sites were investigated in 2010–2011, and analyzed using metric multidimensional scaling, cluster analysis and generalized additive models. Two major gradients driving the differences in mollusc species composition were revealed. The main direction of compositional changes was associated with the water table gradient, governing a species turnover from inundated and strongly water-logged sites occupied mostly by aquatic mollusc species, to moderately wet sites with the predominance of fen and meadow species. The second most important gradient for molluscs was that of mineral richness. For vegetation, three major gradients explained the changes in species composition. The highest importance was assigned to the nitrogen-to-phosphorus availability gradient (defined as a shift from N-limited to P-limited vegetation), followed by the water table gradient, and the mineral richness gradient. Our results demonstrate that the impact of mineral richness gradient, which has been often reported as the major determinant of compositional changes of fen molluscs and vegetation, can be exceeded by other ecological gradients of comparable variation. We also document for the first time that the main species turnover of fen vegetation is not accompanied by the analogous change in species composition of mollusc assemblages, due to a different sensitivity of these taxa to particular environmental factors (i.e. water level dynamics and type of nutrient limitation).  相似文献   

15.
有机锡污染与海产腹足类性畸变   总被引:24,自引:2,他引:24  
施华宏  黄长江 《生态学报》2001,21(10):1711-1717
综述了海产腹足类性畸变发生的原因和形态变化,并对利用海产腹足类性畸变进行有机锡污染的生物监测,海产腹足类性畸变的生态毒理学等方面的研究进展及我国的研究现状作了详细的介绍。  相似文献   

16.
Organismal taxonomy is often based on a single or a small number of morphological characters. When they are morphologically simple or known to be plastic, we may not have great confidence in the taxonomic conclusions of analyses based on these characters. For example, calyptraeid gastropod shells are well known for their simplicity and plasticity, and appear to be subject to frequent evolutionary convergences, but are nevertheless the basis for calyptraeid taxonomy. In a case like this, knowing how the pattern of relationships inferred from morphological features used in traditional taxonomy compares to the patterns of relationships inferred from other morphological characters or DNA sequence data would be useful. In this paper, I examine the relative utility of traditional taxonomic characters (shell characters), anatomical characters and molecular characters for reconstructing the phylogeny of calyptraeid gastropods. The results of an ILD test and comparisons of the recovered tree topologies suggest that there is conflict between the DNA sequence data and the morphological data. Very few of the nodes recovered by the morphological data were recovered by any other dataset. Despite this conflict, the inclusion of morphological data increased the resolution and support of nodes in the topology recovered from a combined dataset. The RIs and CIs of the morphological data on the best estimate topology were not any worse than these indices for the other datasets. This analysis demonstrates that although analyses can be misled by these convergences if morphological characters are used alone, these characters contribute significantly to the combined dataset.  © 2003 The Linnean Society of London . Biological Journal of the Linnean Society , 2003, 78 , 541–593.  相似文献   

17.
Five cyrtocrinid crinoid taxa previously unknown from the epicratonic deposits of Poland, as well as associated millericrinids and isocrinids, are described. The studied materials were derived mainly from the Lower and Middle Oxfordian, but crinoids are also from uppermost Callovian and/or lowermost Oxfordian sediments of the Polish Jura Chain (southern Poland). The crinoids, preserved as more or less complete (e.g., basal circlets) cups, include Lonchocrinus dumortieri, Phyllocrinus belbekensis, Remisovicrinus polonicus, Remisovicrinus aff. polonicus, Tetracrinus moniliformis and Sclerocrinus sp. The occurrence of Remisovicrinus polonicus in the late Middle Oxfordian of the southern Poland is confirmed. Moreover, the present study extends the geographic range of all cyrtocrinid species studied and discusses their unusual environmental adaptations.  相似文献   

18.
This paper presents a review and critical analysis of the literature on Devonian floras of the Iberian Peninsula. Although the known outcrops of Devonian strata in the Iberian Peninsula are marine, in some cases, a few fragmentary remains of vascular plants are associated with faunal remains. Records include largely specimens from the Lower Devonian of Barrancos (Alentejo, Portugal) and the Upper Devonian of Sierra de Hornachos in Badajoz province, southwest Spain; the remainder consists of drifted plant fragments from scattered sites in the Iberian Peninsula ranging in age from Lochkovian to Upper Devonian-Earliest Carboniferous. The vegetation inferred for the Lower Devonian of the Iberian Peninsula is mainly based on palynological data and corresponds to herbaceous types characterised by bryophytes, rhyniophytes (Horneophyton, Cooksonia, Rhynia), trimerophytes (Psilophyton, Pertica and Hostinella), primitive lycophytes (Drepanophycus) and incertae sedis such as Nothia and Chaleuria, all flora that developed near the coast in low-lying and, at least periodically, wet areas. In the Middle Devonian, two vegetation strata can be recognised: herbaceous (Psilophyton) and semi-arboreal (Cladoxylales). Although three levels of vegetation in the Upper Devonian, have been described from outcrops worldwide, the scarce available data from the Iberian Peninsula only indicate an arborescent lycopsid vegetation and species with uncertain botanical affinity such as Sphenopteridium keilhauii Nathorst.  相似文献   

19.
Antiarchi (Pisces, Placodermi) from the Devonian of central and southern European Russia (Central Devonian Field) are studied. Antiarchs belong to three families, the Asterolepididae, Remigolepididae (suborder Asterolepidoidei), and Bothriolepididae (suborder Bothriolepidoidei). The diagnoses of the order, two suborders, three families, and five genera (two of which are new) are given. Sixteen species, including one new, are described; ten taxa are determined in open nomenclature. Morphological structures of representatives of these families are considered in detail. Classifications of antiarchs and their position in the system of the lower vertebrates are discussed. Devonian vertebrate localities of central and southern European Russia that have yielded antiarchs are listed. Each locality is characterized by its ichthyoassemblage.  相似文献   

20.
New spiriferids (Brachiopoda) are described from the Lower and Middle Devonian of northeastern Russia: Tatjanaspirifer iskrensis sp. nov. and T. magnificus sp. nov. (family Reticulariidae); Cyrtina inveterata Baranov, sp. nov. and Blodgettospirifer gen. nov. with type species B. lezhoevi sp. nov. (family Cyrtinidae).  相似文献   

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