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1.
The conodont fauna from the Willara Formation, a carbonate-dominated stratigraphic unit widely distributed in the subsurface Canning Basin of Western Australia, is represented by 41 species, including a new species, Erraticodon neopatu Zhen n. sp. The Jumudontus gananda and Histiodella altifrons biozones are recognized in the lower and upper parts, respectively, of the Willara Formation. Deposited primarily in shallow nearshore settings, the Willara Formation is characterized by the occurrence of predominantly long-range coniform species of Triangulodus, Scalpellodus, Drepanoistodus, Drepanodus, and Kirkupodus. Several widely distributed age-diagnostic species, including Histiodella altifrons, Histiodella holodentata, Histiodella serrata, and Jumudontus gananda, serve as keys for biostratigraphic analysis and correlation. Our study also shows that the basal and top boundaries of the Willara Formation are diachronous across the basin, extending from the middle Floian (Oepikodus communis Biozone) to middle Darriwilian (Histiodella holodentata-Eoplacognathus pseudoplanus Biozone). This contribution provides crucial new biostratigraphic data for precise correlation of the Willara Formation with its time equivalents regionally and internationally.  相似文献   

2.
A new triprojectate pollen genus, Novemprojectus, is described from a middle Eocene sample from the Eureka Sound Formation on Kanguk Peninsula of Axel Heiberg Island, the Canadian Arctic. The type species of the genus is Novemprojectus traversii.  相似文献   

3.
Abstract

The two recently collected mammalian dentary fragments from the Eocene Youganwo Formation of Guangdong Province, southern China, are referred to the anthracotheriid species Anthracokeryx naduongensis based on phylogenetic analysis and size comparison. One of these specimens (SYSU-M-1) is the first mammal fossil described from the Youganwo Formation. It was attributed previously to the perissodactyl genus Lunania. Anthracokeryx naduongensis was described originally from the lower upper Eocene Na Duong Formation in Northern Vietnam. The second record of this species supports a basal upper Eocene correlation for the Youganwo Formation, which was estimated previously as middle or late Eocene.  相似文献   

4.
Previously undescribed notharctine primate fossils are reported from the early Eocene San Jose Formation, San Juan Basin, New Mexico, and the early Eocene Wasatch Formation, southern Wyoming. These collections include the most complete specimens yet discovered of the poorly known species Copelemur tutus and Copelemur praetutus; the first upper dentitions of Cantius angulatus and Cantius frugivorus from the type area of these taxa; and fossils attributable to two new notharctine species, Copelemur australotutus and Smilodectes gingerichi. These new fossils reveal that current ideas concerning notharctine phylogeny are incorrect. Two major, monophyletic clades are apparent within the subfamily: the tribe Copelemurini, consisting of the genera Copelemur and Smilodectes, and the tribe Notharctini, comprising the genera Cantius, Pelycodus, and Notharctus. Analysis of the paleobiogeographic distribution of the Copelemurini indicates that this clade was limited to more southerly regions of western North America during early Eocene time. Northward migration of more tropical habitats during the late Wasatchian and early Bridgerian in western North America, associated with an overall climatic warming trend through the early and middle Eocene, appears to have allowed several mammalian taxa, including Smilodectes, to extend their ranges northward during this time interval. Such taxa thus possess diachronous distributions and have been partly responsible for the long-standing confusion regarding the biostratigraphic correlation of early Eocene faunas from New Mexico with those from Wyoming. Based on several taxa which are also known from the Wasatchian of Wyoming, the age of the San Jose Formation appears to be middle Wasatchian.  相似文献   

5.
A new genus and species of omomyid primate is described from the middle Eocene (Lutetian) Lülük Member of the Uzunçarşidere Formation, Orhaniye Basin, north-central Anatolia, Turkey. This is the first Eocene primate to be reported from the vast area between Switzerland and Pakistan. The new taxon is currently represented by a single dentary fragment, limiting the scope of morphological comparisons that can be made with related taxa. Nevertheless, its dentition differs fundamentally from that of contemporary European microchoerids. The new taxon most closely resembles North American middle Eocene omomyines such as Mytonius hopsoni, and it is therefore interpreted as a member of the Asian/North American omomyine radiation. Its occurrence on the Pontide microcontinent must have resulted from sweepstakes dispersal across the intervening Tethyan barrier that separated the Pontides from adjacent parts of Eurasia during the Lutetian. Sweepstakes dispersal by various terrestrial mammal clades, especially rodents and primates, was facilitated by Eocene greenhouse climatic conditions, which promoted extreme precipitation events and frequent flooding of major river drainages.  相似文献   

6.
This paper presents for the first time the inventory of the Paleocene and Lower Eocene foraminifers located in the North Pyrenean trough, between the Atlantic Ocean and the neighbourhood of the town Pau. They have been studied from three outcrops. The Bidart Beach section shows the Lasseube Formation from the Cretaceous/Paleogene boundary to the base of the P 3a zone. The Loubieng Quarry section, near Orthez, represents the upper P 3a zone and the lower P 3b zone as well as the Lasseube Formation / Pont Labau Formation boundary. The interval between the upper part of the P 3b zone and the upperest part of the P 5 zone crops out along the Gan - Rébénacq road with a hiatus located at the Paleocene / Eocene boundary, the whole interval belonging to the Pont Labau Formation. 394 taxons of foraminifers are present in this formations: 349 benthic and 45 planktonic species. The Velasco type benthic foraminifers show a middle bathyal depositional environment, with a paleobathymetry included between 500-600 m and 1000 m: Nuttallides truempyi, Osangularia velascoensis, Bulimina trinitatensis. The Midway type species which were transported by the turbidite currents from the lower to middle neritic environments are frequent as well as the Cretaceous reworked species. The species number is low: 29 in the iridium layer of the Cretaceous/Paleogene boundary (P 0 zone). Fauna grows rich quickly in the Pα zone reaching 129 species. The diversity grows up progressively from P α to the P 4a zone (NP 8). The disappearances are rare until his horizon, but their number is bigger than the number of appearances from the P 4b zone. It reaches their maximum between the P 4c zone and the P 5 zone. It shows that the decline of the Paleocene fauna begins around 2 million years before the thermal event of the Paleocene / Eocene boundary in the Aquitaine sections. The disappearances stay important in the Lower Eocene - Ypresian, but the appearance of lots of Eocene species show that the fauna renewal is located in this stage. The Cretaceous taxa dominate in the Paleocene benthonic fauna. The appearance or the disappearance of some species has a stratigraphic value in the Aquitaine region: the disappearance of Coryphostoma incrassata in the P 1b zone, the appearances of Plectina dalmatina, Elongobula grata (P α); Bulimina tuxpamensis (P 2); Tritaxilina cubensis, Thalmannita madrugaensis (P 3a); Svenia bulbosa (P 3b); Discorbis perovalis (P 4a/NP 7); Elongobula pulchra, E. pupa, Asterigerina bartoniana, Neorotalia gr. tuberculata (P 4a/NP 8); Bigenerina pannonica, Pentellina pseudosaxorum (P 5/NP 9-10).  相似文献   

7.
《Comptes Rendus Palevol》2018,17(6):357-365
The middle Eocene Pondaung Formation in Myanmar has yielded a rich mammalian fauna including several Primate taxa. Hyaenodonta are known by the genera Kyawdawia, Yarshea, Orienspterodon, and two other indeterminate taxa. We describe here new material of Kyawdawia, including some morphological details, a new species of the hypercarnivorous genus Propterodon and an indeterminate species, different from those described earlier in Myanmar, and characterized by a reduction of m3 and would belong to a third lineage with the same evolutionary trend as Galecyon and the Limnocyoninae. The hyainailourines (Orienspterodon) and hyaenodontines (Propterodon) are recorded for the first time in Southeast Asia and these subfamilies appeared in quasi the same time in Europe illustrating probably a profound change in the carnivorous fauna among Laurasia.  相似文献   

8.
<正> 南宁盆地脊椎动物化石地点目前所知不下七处。本文着重记述了1974和1979年笔者采自邕宁县五塘公社莲塘村的石炭兽化石,并对盆地东部下第三系作一初步划分。本文首次报道南宁盆地发现脊椎动物化石,对研究石炭兽的演化、发展和分布,对盆地第三系地层的划分和对比,提供了新的依据。一、化石地点及地层概况莲塘村位于南宁市东北约32公里、五塘圩东5公里、邕宾(南宁—宾阳)公路南侧。石炭兽化石产于莲塘村东约300米远的小煤窑、距地表8.3米深的褐煤层顶板(灰色泥质粉砂岩)中。  相似文献   

9.
The first Sinopa species, S. jilinia sp. nov., from outside of North America is described. It comes from the Huadian Formation, locality Gonglangtou, Jilin Province, north‐east China. The new species represents the northernmost and one of the latest and most complete Asian Prototomus‐like hyaenodontidans known. It also represents one of the youngest specimens of Sinopa, because the age of the Huadian Formation is correlated to the later Uintan and only one doubtful citation of North American Sinopa younger than the early Uintan exists. S. jilinia sp. nov. is characterized by having m3 clearly smaller than m1, very strong and extended labial molar cingulids, backward leaning protoconids in all molars and its m3 cristid obliquum joining the postvallid very labially. With S. jilina, Sinopa is the first hyaenodontidan genus known to be present on two continents during the time interval between the earliest Eocene (c. 55.0 Ma) and latest middle Eocene (40 Ma). Its occurrence in the Huadian Formation supports the idea of a faunal exchange between North America and Asia in the early middle Eocene, a hypothesis formerly based mainly on the presence of the omomyid primate Asiomomys in the Huadian Formation, on a small radiation of East Asian trogosine tillodonts and on a couple of perissodactyl genera shared between the middle Eocene of North America and the Irdinmanhan of East Asia. As with the new Sinopa species, these Asian taxa had their closest relatives in North America.  相似文献   

10.
A complete post-incisor upper dentition and a left mandible with P/3-M/3 of the proviverrine hyaenodontid (Creodonta: Mammalia)Paratritemnodon indicus, which was hitherto known by heavily worn P/3-M/3, are described from the uppermost Subathu Formation (Middle Eocene) of the Kalakot-Metka-Mohgala area, Rajauri District, Jammu and Kashmir.P. indicus is most closely related to the North American Early Eocene proviverrine,Tritemnodon; its relationships withProdissopsalis from the Middle Eocene of Europe andPropterodon from the Middle to Late Eocene of China are also close. In the Kalakot Eocene vertebrate community of the Subathu vertebrate bioprovince,P. indicus is the only land dwelling carnivorous mammal against more than 20 species of herbivorous mammals, a majority of which are larger than it. This is viewed as an imbalance in trie community and it reflects an immaturity of the ecosystem supporting the fauna. The scarcity of carnivore remains in the Kalakot mammalian fauna is not an artifact.  相似文献   

11.
Kalyan Halder 《Palaeoworld》2012,21(2):116-130
The Cenozoic marine succession of Kutch, India, is rich in benthic molluscs and other invertebrates, but nautiloids are very scanty. Three nautiloid species, with two being new, are reported here: Deltoidonautilus vredenburgi n. sp. from the Early Eocene Naredi Formation, Cimomia forbesi (d’Archiac and Haime, 1854) from the Middle Eocene Harudi Formation, and Aturia gujaratensis n. sp. from the Early Miocene Khari Nadi and Chhasra formations. Taphonomic and sedimentary features reveal that the Eocene nautiloids were parautochthonous whereas the Miocene species might have been transported post-mortally for some distance. Palaeobiogeographic distribution of the Cenozoic nautiloids of the Indian subcontinent and other parts of the world reveals that though the genera are pandemic the species are often endemic to a basin or a province. Specific endemism and pattern of broad faunal similarity of nautiloids among different provinces within the Tethys Realm (sensu Harzhauser et al., 2002) mimic those of the benthic molluscs during the Palaeogene.  相似文献   

12.
A new genus and species of tapiromorph, Skopaiolophus burmese nov. gen., nov. sp., is described from the middle Eocene Pondaung Formation in central Myanmar. This small form displays a striking selenolophodont morphology associated with a mixture of primitive “condylarthran” dental characters and derived tapiromorph features. Skopaiolophus is here tentatively referred to a group of Asian tapiromorphs unknown so far. The occurrence of such a form in Pondaung suggests that primitive tapiromorphs might have persisted in southeast Asia until the late middle Eocene while they became extinct elsewhere in both Eurasia and North America.  相似文献   

13.
The genus Djanaliparkinsonia Kutuzova, 1975 was originally described as an endemic subgenus of the genus Parkinsonia (family Parkinsoniidae of the superfamily Perisphinctoidea) from the Upper Bajocian (middle member of the Degibadam Formation) of the Gissar Range (Uzbekistan). A new species D. alanica sp. nov. is established from the Upper Bajocian Garantiana garantiana Zone (upper member of the Djangura Formation) based on occurrences in the Northern Caucasus (Karachay-Cherkessia). Macroconchs and microconchs of the new species are described from the two localities on the Kuban and Kyafar rivers. Djanaliparkinsonia sp. is identified from the lower subzone of the Parkinsonia parkinsoni Zone of the Kyafar River. The species composition and geographic range of Djanaliparkinsonia are expanded: a species previously described from Germany as Garantiana bentzi Wetzel, 1954 also assigned to the genus. The genus Djanaliparkinsonia is assigned to the subfamily Garantianinae of the family Stephanoceratidae (superfamily Stephanoceratoidea).  相似文献   

14.
A new genus and species of primitive selenodont artiodactyl, Zhailimeryx jingweni, occurs in the late middle Eocene Zhaili Member of the Heti Formation, Yuanqu Basin, Shanxi Province, China. A phylogenetic analysis of dental characters suggests that Zhailimeryx is closely related to Lophiomeryx and other lophiomerycid ruminants of Asia and Europe. Zhailimeryx and other Eocene records of Lophiomerycidae from Asia support an Asian origin for this family, followed by dispersal into Europe both before and after the Grande Coupure. Morphological evidence from Zhailimeryx suggests that ruminant artiodactyls had already undergone substantial diversification prior to the late middle Eocene, and it reopens the issue of whether the higher taxa Tragulina and Pecora are valid expressions of ruminant phylogeny.  相似文献   

15.
Chitinozoans were extracted from Upper Ordovician strata in the northeastern Alborz Range (Kopet Dagh Region); 31 chitinozoan species are recorded. Four successive biozones are recognised within the Ghelli Formation, viz. Tanuchitina fistulosa, Acanthochitina barbata, Armoricochitina cf. nigerica and Ancyrochitina merga biozones. Correlation of these biozones with those of the North Gondwana Domain suggests that the middle and upper parts of the Ghelli Formation range from Late Caradoc to mid Ashgill. The number of species in common with the North Gondwana Domain suggests a close relationship between Iran and North Gondwana. However, there are a number of cosmopolitan species occurring in the Ashgill. Three new species are described: Armoricochitina alborzensis, Armoricochitina iranica and Ancyrochitina persica.  相似文献   

16.
《Palaeoworld》2023,32(3):523-546
The stratigraphic correlation of the Kuma Formation from the south of the Russian Platform and the Crimea-Caucasian region has been a matter of debate for decades. A bed-by-beds study of dinocysts and nannoplankton from the the Kuma Formation made it possible to recognize a sequence of biotic events, important for defining and correlating the biozones. At the Bakhchisarai limestone quarry, six dinoflagellate zones and six nannoplankton zonal units were recognized, assignable to the Middle Eocene Lutetian and Bartonian stages. Our paleoecological analyses of the organic-walled microphytoplankton assemblages and of the palynofacies indicate that the the Kuma Formation deposited in the inner shelf zone, probably of anoxic and eutrophic settings within the Pontic-Transcaucasian magmatic belt. Assemblages of organic-walled microphytoplankton comprise potentially toxic dinoflagellate species of Alexandrium. The Middle Eocene Climatic Optimum event is recorded in the upper part of the the Kuma Formation, presumably indicated by the Dracodinium rhomboideum dinoflagellate zone, which is characterized by an acme of Dracodinium laszczynskii Gedl and the lowest occurrence of nannofossils Reticulofenestra bisecta (Hay, Mohler and Wade) Roth. Two new species are described: Pentadinium rugosum Vasilyeva, n. sp. (dinocyst) and Corannulus tauricum Musatov, n. sp. (nannofossil). The bioevents and biozones established herein are significant for correlations of the Middle Eocene of the Crimean Peninsula and the south of the Russian Platform.  相似文献   

17.
Most omomyids are relatively small bodied (e.g. <500 g), but beginning in the middle Eocene, some omomyids began to grow larger. The largest omomyids occur in the late middle Eocene during the Uintan NALMA, reaching an estimated body mass over 1 kg. The hind limb skeleton of small omomyids is relatively well known, and is generally thought to show active arboreal quadrupedal and leaping adaptations. New postcranial specimens of previously unknown elements from the larger Uintan omomyids, Ourayia (two species), Chipetaia lamporea, and Mytonius hopsoni have recently been recovered from the Uinta Formation, Utah, and from the Mission Valley Formation, California, and they provide additional information concerning their locomotor behavior.The new specimens include several distal tibiae, partial calcanei, a complete talus and a proximal first metatarsal of Chipetaia; distal femora, distal tibiae, cuboids, and partial calcanei of Ourayia uintensis; a complete calcaneus of Ourayia sp.; and a partial calcaneus and talus of Mytonius. Metric analysis of these elements, together with qualitative observations of non-metric traits, indicate that Ourayia and Chipetaia show equal or greater development of traits associated with leaping behavior (including elongation of the calcaneus, navicular and cuboid) than do smaller omomyids from North America. The elements of Mytonius, although fragmentary, lack some leaping features that are well-developed in Ourayia and Chipetaia, suggesting that Mytonius may have relied more on arboreal quadrupedal locomotion than on leaping.  相似文献   

18.
The study of the Late Eocene (Priabonian) otolith associations from Possagno, North-East Italy, and from the Synclinal d’Allons in Haute Provence, South-East France, allows for the reconstruction of a teleost fauna of 55 taxa, which is the most diversified assemblage presently known from the Upper Eocene Paleo-Mediterranean basin. Thirty-six taxa are identified at the species level, and five of those are new: “genus Alepocephalidarum” astrictus, “genus Lophiiformorum” canovae, “genus Agonidarum” sudans, “genus Uranoscopidarum” cochlearis and Aseraggodes laganum. In the Synclinal d’Allons, the otolith associations reflect a tropical to subtropical neritic environment with a few mesopelagic fishes. At Possagno, the associations indicate an environment that changed from one that was deep and exposed to the pelagic realm and then evolved to a more shallow sea with a well-diversified benthic life and less mesopelagic fishes. A paleobiogeographical analysis of all known data on Priabonian otoliths, worldwide, shows clearly a western Atlantic (Louisiana) and an eastern Atlantic-Paleomediterranean association. In the eastern Atlantic-Paleomediterranean association, the Aquitaine association not only differs from the Possagno-Allons association in function of its more distant geographical position, but also by its stronger oceanic character in the southern part of the basin, and by the occurrence in the north, of a very shallow water facies (Saint-Estephe Formation) that contains some taxa which are known nowhere else in the Priabonian. The Ukraine fauna is characterized by a high number of species, which have an Oligocene record in other European sites. The northern geographic location of Ukraine, combined with the good connections to both the North Sea Basin and the Turgai street can provide the explanation. Many Oligocene species (or their close relatives) probably already existed at Eocene times in more northern regions, but could penetrate only in more southern European seas since the strong cooling at the beginning of the Oligocene.  相似文献   

19.
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   

20.
A new species of fossil wood, Tapirira clarnoensis, is described from a probable late Eocene deposit in the Clarno Formation of Oregon known locally as the Nut Beds. The wood represents, to the knowledge of the writer, the earliest occurrence of Tapirira in the fossil record and the only occurrence of the genus outside its present neutropical range of distribution.  相似文献   

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