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1.
A new artiodactyl of moderate size, Rajouria gunnelli nov. gen., nov. sp., is described on the basis of several dentaries, maxillae and isolated teeth from the middle Eocene Subathu Group of the Kalakot area, Rajouri District, Jammu and Kashmir, India. Despite its general resemblance with the family Dichobunidae by the retention of a paraconid on m1-2 and a simple P4 where endocristids do not form an anterior loph, this taxon shares with Raoellidae two unambiguous characters: the presence of a hypoconid on p4, and an asymmetrical P4. The phylogenetic position of the new taxon within the Cetacea–Raoellidae clade is strongly supported by seven non ambiguous synapomorphies, among which a cristid obliqua on lower molars anteriorly pointing towards the postectoprotocristid, and a P3 with only two roots. The presence of a new basal raoellid in the middle Eocene Subathu Group sheds new light on the phylogeny and paleobiogeography of raoellid artiodactyls.  相似文献   

2.
The Middle Eocene (Lutetian) strata constituting the top of the Subathu Formation in Jammu and Kashmir, have yielded a large number of ziphodont crocodilians. The affinity of these serrated-toothed crocodiles has been assigned to the Eusuchian Pristichampsus rather than to the Sebecosuchia. The teeth are morphologically diverse, strongly fluted with serrations varying from fine to coarse. It is believed that the Kashmir ziphodont crocodiles are migrant descendants of Chinese forms which spread across the Indian sub-continent. Their presence in Europe may be accounted by migration along with Asiatosuchus across the Turgai Straits sometime in the Early Eocene.  相似文献   

3.
Qian Li 《Palaeoworld》2018,27(4):490-505
New cricetid (Cricetops dormitor, Eocricetodon sp., Eucricetodon cf. E. wangae, Pappocricetodon schaubi) and dipodid (Allosminthus gobiensis n. sp., Allosminthus ernos, Allosminthus uniconjugatus, Allosminthus cf. A. majusculus, Primisminthus shanghenus, Sinosminthus sp.) occurrences from the “Lower Red”, “Middle Red”, “Middle White” and “Upper White” beds of the Erden Obo section in Nei Mongol, China are reported. They are first discovered in these horizons. On the basis of the comparison of the rodent assemblages, we consider that the age of the “Upper White” beds is early Oligocene, the age of the “Middle Red” and “Middle White” beds is probable more similar to the age of late Eocene Houldjin Formation and lower part of Chaijiachong Formation, and the age of the “Lower Red” beds is correlative to the Sharamurunian. The diversity of ctenodactyloid, dipodid, and cricetid appears to change, and the turnover in rodent fauna possibly responded to the environmental and climate change towards the end of middle Eocene.  相似文献   

4.
Fragmentary remains of sea turtles (Cheloniidae sensu lato: Argillochelys sp., Puppigerus nessovi Averianov, 2005, and Cheloniidae gen. indet.) from the Ikovo locality (Lugansk Region, Ukraine; Lower Lutetian, Middle Eocene) are described. The genera Argillochelys and Puppigerus are recorded for the first time in Eastern Europe. The turtle assemblage from Ikovo is similar at the generic level to West European assemblages (Belgium, Great Britain) of approximately the same age (Lower-Middle Eocene). In the presence of P. nessovi, the Ikovo assemblage is similar to that from the Middle Eocene Dzheroi 2 locality (Uzbekistan).  相似文献   

5.
We describe six proviverrine species from the Early Eocene of France. Three species are new: M inimovellentodon russelli sp. nov. from Mutigny [mammal palaeogene (MP)8 + 9], B oritia duffaudi sp. nov. from La Borie (MP8 + 9), and L eonhardtina godinoti sp. nov. from Grauves (MP10). We describe new specimens and propose new generic combinations for three species from MP10: Protoproviverra palaeonictides, Matthodon menui, and Oxyaenoides lindgreni. We also propose a new generic combination for the primitive Eoproviverra eisenmanni (MP7). Matthodon menui was previously considered as a possible oxyaenodontan, but the new fossils clearly support its reference to Hyaenodontida. Leonhardtina godinoti and Ma. menui are the oldest occurrences for these genera, which were previously unknown before the Middle Eocene. Moreover, the discovery of the proviverrine Mi. russelli in Mutigny implies that the Proviverrinae dispersed in Northern Europe between biozone Palaeocene‐Eocene (PE) III (Abbey Wood) and biozone PE IV (Mutigny). This also supports a homogenization of the European faunas during the Early Eocene. The dispersal is concomitant with the disappearance of the oxyaenodontans, arfiines, and sinopines (Hyaenodontida) from Europe. The proviverrines may have filled the ecological niches left vacant by the disappearance of the other carnivorous mammals. With 20 genera and over 30 species, proviverrines were successful in Europe. We performed the first phylogenetic analysis comprising almost all the Proviverrinae. Our analyses indicate that the Proviverrinae diversified greatly during the Early Eocene Climatic Optimum and show a general trend towards specialization throughout the Eocene. © 2014 The Linnean Society of London  相似文献   

6.
In Europe, faunas of squamates (lizards and snakes) from the middle Eocene are very poorly known, with the exception of those from the level MP 16 (latest middle Eocene). From the MP 11-MP 15 interval, squamates were previously reported only from Messel (MP 11, earliest middle Eocene) and from the untere and obere Mittelkohle of Geiseltal (MP 12 and MP 13 respectively) in Germany. The present report describes the middle Eocene assemblage of squamates from Lissieu (France), the first fauna reported from the level MP 14. Whereas fossils from Messel and Geiseltal are mostly articulated skeletons, fossils from Lissieu are represented by disarticulated bones; such fossils may be more easily compared to those from other Cenozoic localities, in which bones are almost always disarticulated. The fauna from Lissieu is more diverse than those from the Geiseltal sites and approximately as diverse as that from Messel as they are presently known; it is comprised of 17 distinct taxa. These taxa cannot be all identified to the species or genus level. They belong to iguanids, gekkonids, lacertids, anguids, thecoglossan platynotans, ophidians incertaesedis, boids, ?tropidophiines, “tropidophiids” incertaesedis, booids incertaesedis, and perhaps russellophiids. The fauna includes several new taxa but only a presumed tropidophiine snake may be named on the basis of the available material. The fauna from Lissieu is a mixture of taxa restricted to the middle Eocene and taxa known from older or younger levels. Taxa shared by Lissieu and the few other localities from the middle Eocene of Europe are rare. This fauna from Lissieu represents a stratigraphical landmark for the middle Eocene.  相似文献   

7.
A rich vertebrate fauna is described from the Middle Muschelkalk (Anis, Triassic) north of Gottingen, West-Germany. Completely preserved juvenile fishes ofEosemionotus vogeli Fritsch 1906 occur besides teeth of selachians, scales and some bones of actinopterygians and actinistians and bones of nothosaurs. Genus and species ofEosemionotus vogeli is described and redefined. These findings and search in the literature demonstrate that a rich vertebrate fauna existed in the sea of the Middle Muschelkalk; the contrary is accepted generally.  相似文献   

8.
A sea snake vertebra from the Middle Eocene (Kuma Horizon) of the vicinity of the town of Bakhchisarai (Crimea) is referred to Palaeophis nessovi Averianov, 1997, which was previously recorded in the Middle and Upper Eocene of northern and western Kazakhstan. P. udovichenkoi Averianov, 1997 described from the Crimea based on the material from the Prolom locality (Bartonian-Priabonian?) is a junior subjective synonym of P. nessovi. A vertebra from the Belaya Skala locality (Middle Eocene, outskirts of the town of Belogorsk) is determined as Palaeophis sp.  相似文献   

9.
Eocene-Oligocene deep-sea benthonic foraminifera in D.S.D.P. Site 277 in the southwest Pacific have been analyzed to determine the benthonic foraminiferal response to the development of the psychrosphere near the Eocene/Oligocene boundary. Biostratigraphic ranges of 41 taxa show that 23 taxa are found throughout the Late Eocene to Early Oligocene sequence, while 18 taxa exhibit first or last occurrences. Comparison of the faunal changes in Site 277 with a benthonic foraminiferal oxygen isotope record shows that the development of the psychrosphere did not have a profound effect upon the benthonic foraminifera, and the overall faunal change preceding and subsequent to the bottom-water circulation event occurred gradually. The inferred water-mass event affected the relative abundance of one species, Epistominella umbonifera. The lack of major faunal changes at the Eocene/Oligocene boundary in Site 277 probably reflects either wide environmental tolerances of the benthonic foraminifera, or a bottom-water temperature change less than 3°C.Examination of previously published benthonic foraminiferal biostratigraphic data from D.S.D.P. Sites 167, 171, 357, 360, 363, and 400A, and deep-sea ostracode data from D.S.D.P. Leg 3 show faunal changes occurred during discrete intervals in the Middle Eocene-Early Oligocene. The faunal patterns from these data and from Site 277 show that the Eocene/Oligocene cooling event did not cause rapid, catastrophic changes of the benthonic faunas of the open ocean, although significant faunal changes are associated with the water mass event in Sites 167, 171 and 400A.The benthonic faunal changes in Middle Eocene-Early Oligocene time are consistent with the gradual decrease of inferred bottom-water temperatures, based on previously published oxygen isotopic data. The δ 18O Eocene/Oligocene enrichment of 0.76‰ is a major event in the Southern Ocean oxygen isotopic record, but is considerably less in magnitude than the 1.75-2.00‰ change that occurred gradually from mid-Early Eocene to the Eocene/Oligocene boundary. The benthonic foraminiferal and isotopic data indicate that bottom-water circulation may have developed during the Middle Eocene to Early Oligocene interval, with the 3°C bottom-water cooling near the Eocene/Oligocene boundary representing part of this development.  相似文献   

10.
The known fossil record of crocodyliforms in Europe during the Paleogene is significantly biased, in that the fauna of Western Europe is far better sampled and understood compared to that of Eastern Europe. We describe in detail all known crocodyliform remains from the middle Eocene (Lutetian) Ikovo locality in Ukraine. We conclude that at least two taxa were present: a moderate to large-sized Tomistominae indet. similar to the basalmost known tomistomines, and the small-sized basal alligatoroid cf. Diplocynodon sp. Despite its scarcity, this is the first basal alligatoroid material reported from Eastern Europe (as part of post-Soviet countries) and the easternmost record of diplocynodontines in Europe so far. An allegedly freshwater cf. Diplocynodon sp. contributes a rare faunal element to the vertebrate assemblage of the Ikovo locality, otherwise dominated by resident or facultative marine taxa. The fossil record and historical paleobiogeography of crocodyliforms from the Paleocene and Eocene of Europe are reviewed. As it has been already known, the middle Eocene fauna of crocodyliforms proves to be taxonomically diverse and complex. Its constituent lineages geographically originated in Asia or North America (Diplocynodontinae, Asiatosuchus-like crocodyloids, Planocraniidae), North America (derived alligatorines), Africa (Tomistominae), and Gondwana (ziphodont mesoeucrocodylians Iberosuchus and Bergisuchus), with possible subsequent speciation in Europe. We propose a novel hypothesis of Asian origins of European diplocynodontines, which will be explicitly tested in future studies. The revealed similarities between crocodylians and turtles from the Ikovo locality and those from Western Europe support the presence of a single Pan-European biogeographical zone during the middle Eocene, distinct from that of Asia.  相似文献   

11.
Most adapiform primates from North America are members of an endemic radiation of notharctines. North American notharctines flourished during the Early and early Middle Eocene, with only two genera persisting into the late Middle Eocene. Here we describe a new genus of adapiform primate from the Devil’s Graveyard Formation of Texas. Mescalerolemur horneri, gen. et sp. nov., is known only from the late Middle Eocene (Uintan) Purple Bench locality. Phylogenetic analyses reveal that Mescalerolemur is more closely related to Eurasian and African adapiforms than to North American notharctines. In this respect, M. horneri is similar to its sister taxon Mahgarita stevensi from the late Duchesnean of the Devil’s Graveyard Formation. The presence of both genera in the Big Bend region of Texas after notharctines had become locally extinct provides further evidence of faunal interchange between North America and East Asia during the middle Eocene. The fact that Mescalerolemur and Mahgarita are both unknown outside of Texas also supports prior hypotheses that low-latitude faunal assemblages in North America demonstrate increased endemism by the late middle Eocene.  相似文献   

12.
Crocodylian remains are collected in 39 fossil-bearing localities but only in seven localities specimens with reliable taxonomic attributions, at least to genus level have been collected. Three species have been reported from the early Lutetian Purga di Bolca site: Pristichampsus cf. Pristichampsus rollinati, Asiatosuchus sp., Hassiacosuchus sp. (=Allognathosuchus sp.). The three crocodilians discovered at Purga di Bolca have been reported also from Geiseltal and Messel (Middle Eocene, Germany). Bolca at that time was part of a Tethysian archipelago and no mammals have been found there till now. Crocodilians and turtles clearly arrived from the European mainland across a marine water barrier. Among the other fossiliferous localities of Veneto, very interesting is the Monte Zuello site, of late Middle Eocene age, yielding a longirostrine crocodilian, Megadontosuchus arduini, a tomistomine species. Tomistomines are known in contemporaneous sediments of both Europe and Africa, but the European forms Dollosuchus and Kentisuchus seem the closest taxa. Remains of Oligocene age have been collected in Veneto and Liguria, but the fossils discovered in the second region are teeth or fragmented bones. The fossil crocodilians of Monteviale (Veneto), of Early Oligocene age, have been assigned to two species but they have been recently all identified as Diplocynodon ratelii, known from several European sites of Late Eocene, Oligocene and Miocene age. This species arrived in the Monteviale area from the European mainland across a narrow sea. Several crocodilian fossils of Miocene age are very fragmentary or represented by isolated teeth. In the Middle and Late Miocene of Sardinia, a well-established species, Tomistoma calaritanum is present. Remains of Tomistoma of the same age have been reported in some localities in Tuscany, Apulia, Sicily and Malta. In the Mediterranean area, the genus is known from European and African sites (of older age). The colonisation of Europe by this genus is the result of a dispersion from Africa (or less probably from Asia). During Late Miocene Sardinia and Tuscany belong to the same palaeobioprovince characterized by the Oreopithecus-Maremmia fauna. In Tuscany, a crocodilian identified as Crocodylus bambolii is present in the late Miocene site of Monte Bamboli. If the generic attribution of this form is correct, its ancestors must have arrived from Africa. Another fossil assemblage of Late Miocene age characterizes the Apulia-Abruzzi palaeobioprovince (Hoplitomeryx-Microtia fauna) and testifies complete isolation between the two palaeobioprovinces. In this last area, remains of Crocodylus sp. have been collected in coastal sandstones at Scontrone (Abruzzi) and in several fissure fillings of Gargano of slightly younger age. The ancestors of this species arrived from Africa while no African elements are present among the mammalian fauna. The dispersion of the genus Crocodylus in the Italian palaeoislands may have taken place once, with allopatric differentiation of the two populations (Tuscany-Sardinia and Apulia-Abruzzi) or twice with independent colonisation of each area.  相似文献   

13.
描述了来自内蒙古二连盆地的戈壁兔新材料,并命名了一个戈壁兔新种Gobiolagus aliwusuensis sp.nov.。化石产于额尔登敖包剖面中阿里乌苏地点,传统地层划分中的下红层,时代约为中始新世。该种具有中等个体,P3主尖前壁具有小的附尖,P4颊侧有两个明显的尖。这些化石材料保存了戈壁兔材料中仅有的完整上齿列,其中的P2和M3形态是首次报道,为了解亚洲早期兔形类的演化增加了新的信息。  相似文献   

14.
《Comptes Rendus Palevol》2013,12(4):191-202
We describe here “miacid” taxa from the Early Eocene Paris Basin locality of Le Quesnoy (Oise, France). We describe the new species Vassacyon taxidiotis, the first European record of this genus. The other “miacids” identified from Le Quesnoy are Miacis latouri and Gracilocyon solei. The P4 of G. solei is described here for the first time. Its morphology (e.g., wide protocone, short postmetacrista) supports a close relationship with Miacis rundlei from Abbey Wood (MP8 + 9, England). The latter species is therefore classified as Gracilocyon rundlei. Three new tooth positions are known for Miacis latouri: P4, p4 and m2. They support its reference to Miacis. These specimens imply that the European species is more basal than the North American species. The fauna from Le Quesnoy shares with Dormaal the presence of Miacis latouri and Gracilocyon solei, but the “miacid” fauna from Le Quesnoy also contains Vassacyon taxidiotis. The presence in Le Quesnoy of the two former taxa supports a reference to MP7 level of the French locality. The presence of three distinct genera in European localities show that the “Miacidae” were diversified in Europe, as previously observed in North America. The genera Gracilocyon, Miacis, and Vassacyon probably dispersed from Europe to North America during the Palaeocene/Eocene boundary.  相似文献   

15.
山东新泰中始新世化石哺乳类新材料   总被引:6,自引:4,他引:2  
本文记述了采自山东新泰的一批中始新世哺乳动物,并主要地与内蒙大苏尼特右旗呼和勃尔和等地“阿山头组”中的哺乳动物做了比较。新泰动物群似应为中始新世早期。  相似文献   

16.
The Eocene (Bartonian) marls of the La Guixa Member and Gurb Member, Vic Marls Formation (Ebro Basin, Catalonia, Spain), contain a very rich and diversified siliceous sponge fauna. The fauna is dominated by hexactinellids; lithistids and other demosponges are rare. It consists of 16 species representing 16 genera. Eleven new species and two new genera are proposed for these sponges: Reguantella cavernosa nov. gen. nov. sp., Regadrella concinna nov. sp. (both Hexactinellida, Lyssacinosa), Eurete clava nov. sp., Pleuroguettardia iberica nov. sp., Aphrocallistes almeriae nov. sp., Hexactinella informis nov. sp. (all Hexactinellida, Hexactinosa), Brachiolites munterensis nov. sp., Centrosia viquensis nov. sp., Callicylix eocenicus nov. sp., Rhizocheton robustus nov. sp. (all Hexactinellida, Lychniscosa), Propetrosia pristina nov. gen. nov. sp. (Demospongia, Haplosclerida). Some genera of sponges in this fauna are still extant, but, in general, the predominant ones are very close in morphology, and, without doubt, closely related to the Late Cretaceous sponges. This fauna also differs considerably, in terms of composition, from most other described faunas of Tertiary sponges from the Mediterranean region, which are dominated by lithistid sponges. Lithistid sponges are rare in this investigated assemblage, which seems most similar to an as yet undescribed Eocene fauna from Italy. There is ecological differentiation in the proportions of particular sponges in various outcrops and/or stratigraphical levels that is clearly associated with water-depth-related controlling factor(s): Munter, Tona and Sta. Cecilia represent the deepest facies, Gurb is intermediate, and St. Roc and Vespella are the most shallow. The exact bathymetric position of the sponge fauna is difficult to estimate, but it seems that 100 m (but probably 200 m and more in the case of the deepest parts) of water depth may be inferred for this facies.  相似文献   

17.
Lithological and micropaleontological studies of core-samples from five boreholes drilled in the northeastern part of the coastal basin of Togo allow for a specification of the stratigraphy and the paleogeography of this area during the Maastrichtian and Paleogene. A lithological analysis reveals a marine series consisting of a Lower Maastrichtian unit, a Middle Paleocene to Eocene unit, and an upper unit attributed to the Continental terminal sensu lato. The biostratigraphical study, based on planktonic foraminifera, has led to a characterization of the basin in terms of biozones ranging from the Globotruncana aegyptiaca to the Abathomphalus mayaroensis biozones and biozones P5 to P11, thus specifying a Middle to Upper Maastrichtian, an Upper Paleocene and a Lower to Middle Eocene units. The paleogeographical evolution of the area shows that the series recorded two sedimentary cycles: the first one stops at the end of the Cretaceous and the second one in the Paleogene.  相似文献   

18.
《Annales de Paléontologie》2017,103(4):271-281
Additional Cambrian Series 3, Stage 5, trilobite fauna comprising Peronopsis sp., Eosoptychoparia cf. Spinosa Gaotanaspis cf. pingzhaiensis and Gaotanaspis cf. transversa have been recorded just immediately above the known Oryctocephalus indicus biozone (Cambrian Series 3, Stage 5) in the Parahio valley section (Spiti region). The FAD of Peronopsis and LAD of Gaotanaspis are used to establish a PeronopsisGaotanaspis concurrent biozone immediately above the Oryctocephalus indicus biozone. The first records of Gaotanaspis cf. pingzhaiensis and G. transversa from the Cambrian of Spiti region and the other faunal elements are correlated with the Peronopsis taijiangensis biozone of the Kaili Formation (South China). The stratigraphic thickness from the base of the O. indicus biozone to the top of the PeronopsisGaotanaspis concurrent biozone in the Kunzam La (=Parahio) Formation and its comparison to the Kaili Formation (South China) indicate a possible stratigraphic condensation in the basal part of the Cambrian Series 3, Stage 5 of the Parahio valley (Spiti). Sedimentological and sequence stratigraphic analysis supports this contention.  相似文献   

19.
We report new examples of Cenozoic cold-seep communities from Colombia, Cuba, the Dominican Republic, Trinidad, and Venezuela, and attempt to improve the stratigraphic dating of Cenozoic Caribbean seep communities using strontium isotope stratigraphy. Two seep faunas are distinguished in Barbados: the late Eocene mudstone-hosted ‘Joes River fauna’ consists mainly of large lucinid bivalves and tall abyssochrysoid gastropods, and the early Miocene carbonate-hosted ‘Bath Cliffs fauna’ containing the vesicomyid Pleurophopsis, the mytilid Bathymodiolus and small gastropods. Two new Oligocene seep communities from the Sinú River basin in Colombia consist of lucinid bivalves including Elongatolucina, thyasirid and solemyid bivalves, and Pleurophopsis. A new early Miocene seep community from Cuba includes Pleurophopsis and the large lucinid Meganodontia. Strontium isotope stratigraphy suggests an Eocene age for the Cuban Elmira asphalt mine seep community, making it the oldest in the Caribbean region. A new basal Pliocene seep fauna from the Dominican Republic is characterized by the large lucinid Anodontia (Pegophysema). In Trinidad we distinguish two types of seep faunas: the mudstone-hosted Godineau River fauna consisting mainly of lucinid bivalves, and the limestone-hosted Freeman’s Bay fauna consisting chiefly of Pleurophopsis, Bathymodiolus, and small gastropods; they are all dated as late Miocene. Four new seep communities of Oligocene to Miocene age are reported from Venezuela. They consist mainly of large globular lucinid bivalves including Meganodontia, and moderately sized vesicomyid bivalves. After the late Miocene many large and typical ‘Cenozoic’ lucinid genera disappeared from the Caribbean seeps and are today known only from the central Indo-Pacific Ocean. We speculate that the increasingly oligotrophic conditions in the Caribbean Sea after the closure of the Isthmus of Panama in the Pliocene may have been unfavorable for such large lucinids because they are only facultative chemosymbiotic and need to derive a significant proportion of their nutrition from suspended organic matter.  相似文献   

20.
A postcranial skeleton of a representative of the palaeognathous Lithornithidae (Aves) is described from the Middle Eocene of Messel in Germany. The specimen is slightly smaller than Lithornis plebius from which it, however, differs in limb bone proportions. It constitutes the latest fossil record of the Lithornithidae in Europe, whose only other Middle Eocene record is a fragmentary tibiotarsus from North America.  相似文献   

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