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1.
The genus Pilgnmella , known from the medial Eocene of Pakistan and northwest India, is a primitive perissodactyl, not an artiodactyl as previously identified. Upper cheek teeth of Pilgrimella , when compared with those of primitive representatives of the Equoidea, Brontotherioidea, Chalicotherioidea, Tapirioidea and Rhinocerotoidea, suggest, however, that Pilgnmella cannot on present evidence be referred to any of the five accepted perissodactyl superfamilies. Pilgrimella may represent a short-lived and hitherto unknown perissodactyl lineage. 相似文献
2.
3.
We document Late Eocene vertebrate footprints from the Tarom Mountains of Iran that represent a significant addition to the record of proboscidean and perissodactyl footprints. These footprints are from sandstones and tuffaceous sandstones of strata equivalent to the Kond Formation that overlie middle Eocene sedimentary rocks and are overlain by Oligocene volcanics. The footprints are preserved at 16 tracksites from 10 distinct stratigraphic levels. The mammal footprints include the oldest known proboscidean tracks, assigned to Proboscipeda enigmatica Panin & Avram and to cf. Proboscipeda isp. Evident perissodactyl tracks are common, tridactyl footprints with distinct digit shapes and proportions assigned to the new ichnogenus and ichnospecies Moropopus elongatus. Footprints of small, hopping, rodent-like mammals are identified as Musaltipes taromi new ichnospecies. Other mammal footprints from the Tarom tracksites are indeterminate, and bird footprints are assigned to Avipeda isp. The Tarom tracksites document the oldest record of proboscidean footprints, and this indicates that proboscideans had reached the northern shore of Tethys by Late Eocene time. The abundance and distinctiveness of the Tarom perissodactyl tracks mirrors the abundance and diversity of moropomorph perissodactyls during the Middle-Late Eocene. The Tarom tracksites are the most extensive record of Eocene vertebrate footprints known from Iran.
http://zoobank.org/urn:lsid:zoobank.org:pub:F430F9DB-728F-4162-9791-DC2A5CC5ED43 相似文献
4.
Alexander Averianov Ekaterina Obraztsova Igor Danilov Jianhua Jin 《Historical Biology》2013,25(9):1115-1122
AbstractThe 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
5.
The origin of chalicotheres (Perissodactyla, Mammalia) 总被引:1,自引:0,他引:1
6.
J.J. HOOKER 《Zoological Journal of the Linnean Society》1984,82(1-2):229-244
Hyracotherium cuniculus Owen, 1842, from Palaeocene–Eocene boundary strata in NW Europe, was formerly considered to be an equoid. It is here placed in Cymbalophus gen. nov. , in the perissodactyl suborder Ceralomorpha, which comprises tapiroids and rhinocerotoids, as one of its most primitive and earliest members. This revised classification is based on an evaluation of its advanced versus primitive character states, and comparison with a variety of other primitive perissodactyls. Cheek tooth occlusal relationships in the early stages of ceratomorph evolution are discussed and contrasted with the fundamental perissodactyl morphotype as represented in Hyracotherium. It is suggested that the Lophiodontidae (formerly considered to be ceratomorphs; may be more closely related to chalicotheres; that the Isectolophidae may be the sister-group of chalicotheres and lophiodonts plus ceratomorplis; and that Cymbalophus is the most primitive known member of the newly restricted Ceratomorpha. Cymbalophus is placed tentatively in the family Helaletidae. 相似文献
7.
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
8.
A NEW PRIMITIVE CHALICOTHERE (PERISSODACTYLA,MAMMALIA) FROM THE EARLY EOCENE OF HUBEI, CHINA 总被引:1,自引:1,他引:0
'I.DESCR1PTIoNorderPerissodactylaOwen,l848SuperfamilyCbalicotherioideacall,l872'Family?EomoropidaeVret,l958GehusDanjiangiagen.nov.TypespeciesDaniiangiapingigen.etsp-nov.DiagnoaisSma1lprimitivecha1icothere(lengthofM/l=8.3mm),skullshallowwithcranialrostrumrelatively1ong,mandibularhorizontalramusandmandibularsymphysisfairlylongandsha1low,teeth1ow-crowned,dentitionformula:3.l.4.3/3.1.4.3.Premolarnonmolariform,P2/2tIenchant,P4/withincipientmesostyle.M/widerthan1engthwithW-shapedectoIoph,… 相似文献
9.
Tabuce R Marivaux L Adaci M Bensalah M Hartenberger JL Mahboubi M Mebrouk F Tafforeau P Jaeger JJ 《Proceedings. Biological sciences / The Royal Society》2007,274(1614):1159-1166
The phylogenetic pattern and timing of the radiation of mammals, especially the geographical origins of major crown clades, are areas of controversy among molecular biologists, morphologists and palaeontologists. Molecular phylogeneticists have identified an Afrotheria clade, which includes several taxa as different as tenrecs (Tenrecidae), golden moles (Chrysochloridae), elephant-shrews (Macroscelididae), aardvarks (Tubulidentata) and paenungulates (elephants, sea cows and hyracoids). Molecular data also suggest a Cretaceous African origin for Afrotheria within Placentalia followed by a long period of endemic evolution on the Afro-Arabian continent after the mid-Cretaceous Gondwanan breakup (approx. 105-25 Myr ago). However, there was no morphological support for such a natural grouping so far. Here, we report new dental and postcranial evidence of Eocene stem hyrax and macroscelidid from North Africa that, for the first time, provides a congruent phylogenetic view with the molecular Afrotheria clade. These new fossils imply, however, substantial changes regarding the historical biogeography of afrotheres. Their long period of isolation in Africa, as assumed by molecular inferences, is now to be reconsidered inasmuch as Eocene paenungulates and elephant-shrews are here found to be related to some Early Tertiary Euramerican 'hyopsodontid condylarths' (archaic hoofed mammals). As a result, stem members of afrotherian clades are not strictly African but also include some Early Paleogene Holarctic mammals. 相似文献
10.
Cédric Del Rio Teng-Xiang Wang Shu-Feng Li Lin-Bo Jia Pei-Rong Chen Robert A. Spicer Fei-Xiang Wu Zhe-Kun Zhou Tao Su 《植物分类学报:英文版》2022,60(6):1440-1452
The fossil record evidences an old origin and diversification of Malvaceae in the Northern Hemisphere. The central Tibetan Plateau was at a low elevation with a monsoon influence during the Eocene, allowing the development of a subtropical flora containing Malvaceae. The taxonomic study of fossils from the Eocene of what is now the Tibetan Plateau is still ongoing. Malvaceae fossils from the Eocene Jianglang flora, are attributed to sub-families Tilioideae and Sterculioideae, and are compared with modern species. A new specimen of Firmiana is described based on a fruit valve with a pinnate venation, the secondary veins starting at the ventral suture and reaching the midvein, and the seeds attached at the proximal part of the ventral suture. This specimen represents the earliest known occurrence of the genus. A new occurrence of Craigia is also reported based on detached membranous valves of a fruit capsule with a prominent fusiform locular area and radiating venation. Based on the fossil record of Firmiana and its modern distribution, we infer that the genus may have originated in East Asia and subsequently diversified in South China and Southeast Asia. The new occurrence of Craigia indicates that the genus was distributed in humid areas in South, Southwest and North China during the Eocene. Both fossil records evidence the important role that the Tibetan region played in the diversification of plants in East and Southeast Asia. 相似文献
11.
新疆布尔津地区晚始新世哺乳动物化石的发现及其意义(英文) 总被引:1,自引:1,他引:0
1995年以来作者等人在新疆准噶尔盆地北缘乌伦古河地区开展了第三纪哺乳动物地层研究工作。在调查研究该区乌伦古河组地层同时 (叶捷等 ,2 0 0 1a ,b) ,为搞清乌伦古河组的区域分布 ,我们在 1 999年和 2 0 0 1年先后两次前往布尔津地区考察了那里的“乌伦古河组”。在布尔津县城西北 1 4km处额尔齐斯河北岸的一片新生代露头 ,长期被视为乌伦古河组 ,因而时代也被定为始新世至渐新世 ,但一直没有确凿的化石依据。 1 999年我们首次在该套地层中采集到哺乳动物化石 ( 990 2 7地点 ) ,2 0 0 1年再次在同一地点、同一层位采集到化石并实测了地层剖面。布尔津的该乌伦古河组地层可大致分为两段 ,下段为富含铁质的砂岩与泥岩互层 ,上段为浅灰绿色砂岩与杂色泥岩互层 ,整套地层的风化表面呈黄棕色。在乌伦古河组建组的乌伦古河流域 ,乌伦古河组则由一套浅灰绿色砂岩与棕灰色含砂泥岩构成 ,整套地层风化表面呈灰白色 (叶捷等 ,2 0 0 1a)。两个地区的乌伦古河组的岩性显然是不同的。野外追索证明 ,这两个地区的两套不同岩性的地层是两个不同沉积盆地的堆积物 ,这两个盆地在乌伦古湖附近 (E87°1 2′)被一由古生代地层构成的山岭隔开。作为地质体 ,这两套地层间没有联系 ,不应当归为同一岩石地层单位。因此 ,布尔津 相似文献
12.
河南潭头、卢氏和灵宝盆地上白垩统一下第三系的划分 总被引:4,自引:3,他引:4
在这篇短文中,根据脊椎动物化石的发现,进一步叙述和讨论了豫西潭头、灵宝和卢氏三个盆地的中、新生代地层的划分问题。在这三个盆地的中、新生代堆积物中,属于晚白垩世的有潭头盆地秋扒组和灵宝盆地的南朝组,后一个盆地还可能存在着时代更早的白垩纪地层。在潭头盆地的高峪沟组和大章组中分别找到中古新世的阶齿兽、中兽科和晚古新世的牧兽科、假古猬科化石;在潭头组中发现原恐角兽类和古脊齿兽类化石,时代为早始新世。在灵宝盆地的项城群中尚未找到哺乳类化石,可能包括古新世和始新世早中期的堆积。卢氏盆地的卢氏组和锄钩峪组以及灵宝盆地的川口组和浑水河组的时代为晚始新世。卢氏组下部和川口组或许可延至中始新世。 相似文献
13.
Abstract: We describe avian remains from Novopskov, a new middle Eocene marine locality in Ukraine. The fossils constitute the most substantial collection of Palaeogene bird bones from Eastern Europe and contribute to a better knowledge of the Paratethyan seabird fauna. Most of the specimens belong to Pelagornithidae (bony‐toothed birds), and two species of very different size can be distinguished. The larger of these is tentatively referred to Dasornis sp., the smaller to Odontopteryx toliapica. The specimens include skeletal elements that were not described for Palaeogene bony‐toothed birds and document previously unknown morphological differences between Palaeogene and Neogene Pelagornithidae. It is argued that the purported crane Eobalearica tugarinovi, from the middle Eocene of Kyrgyzstan, is probably also a bony‐toothed bird. A new genus and species of small Gaviiformes, Colymbiculus udovinchenkoi, is described, which is the earliest fossil record of a loon from Europe, preceding the next oldest specimens by more than 10 myr. The Ukrainian fossils document profound differences between middle Eocene and extant marine avifaunas of Europe, and whereas the middle Eocene Paratethyan avifauna appears to have been similar to that of the North Sea with regard to pelagornithid diversity, the absence of prophaethontids and relative abundance of Gaviiformes may indicate faunistic differences concerning the remaining seabirds. 相似文献
14.
日本已知时代最早的古近纪哺乳动物化石产自九州西部熊本县天草(Amakusa)地区始新世地层赤崎(Akasaki)组以及鹿儿岛县甑岛(Koshiki Islands)相当层位的中甑(Nakakoshiki)组。初步研究显示这两个组产出的哺乳动物分异度较高,包括9个目的至少18种动物。赤崎动物群有3种trogosine裂齿类、2种冠齿兽科全齿类、1种等脊貘科奇蹄类、2种dichobunoid偶蹄类、1种下齿兽科踝节类、1种西瓦兔猴科灵长类、1种未定食虫类以及2种可能的梳趾鼠类。中甑动物群包括1种冠齿兽科全齿类、2种小型雷兽科奇蹄类、1种高冠的下齿兽科踝节类、2种啮齿类和1种细齿兽科食肉类。这两个日本哺乳动物组合很接近早-中始新世界线。由于出现了trogosine裂齿类和雷兽,它们的时代要晚于伯姆巴动物群,极有可能与亚洲大陆阿山头期哺乳动物群相当。这两个动物群还包含了在亚洲大陆没有发现过的几个新种,并具有独特的哺乳动物组合。 相似文献
15.
《Comptes rendus de l'Académie des sciences. Série III, Sciences de la vie》1998,321(11):953-959
In April 1997, several new lower jaw fragments of the primates Amphipithecus and Pondaungia were discovered in the Eocene Pondaung Formation in Central Myanmar by the Pondaung Fossil Expedition headed by the Office of Strategic Studies. These new fossils, when compared together and to Siamopithecus from the Late Eocene of Peninsular Thailand, show additional characters that testify to their anthropoid status, to their common origin and to their resemblance to some African relatives. In this paper we describe the new data displayed by these new Myanmar fossils, we identify the characters that unite these Southeast Asian primates as anthropoids and we examine the relationships of this Southeast Asian group with its African counterparts. 相似文献
16.
内蒙古巴彦乌兰地区始新世哺乳类及相关地层问题 总被引:2,自引:2,他引:0
记述了在内蒙古巴彦乌兰地区发现的4种始新世哺乳动物化石,其中包括1个啮齿类新种──Mergenomys neimongolensis sp.nov。新种与在蒙古共和国发现的属型种M.orientalis的不同在于个体大,下臼齿下外脊和下次小尖相对偏于唇侧。新化石的发现以及对岩石地层的分析表明巴彦乌兰剖面上原认为的伊尔丁曼哈组应包含伊尔丁曼哈及沙拉木伦组两个地层单位。 相似文献
17.
Three-dimensionally preserved skulls of small Paleogene land birds are very rare. Here, we describe a cranium and associated partial postcranial remains of an early Eocene stem group roller (Aves: Coraciiformes) from the London Clay of the Isle of Sheppey (England). The fossil shows features of the skull and vertebral column in great detail. It is distinguished from extant Coraciidae and Brachypteraciidae in several presumably plesiomorphic characteristics, which are likely to reflect differences in diet and/or foraging strategy between Eocene and extant rollers. Preserved stomach contents in other early Eocene fossils indicate that fruits were a regular part of the diet of stem group rollers. The extant Coraciidae and Brachypteraciidae, by contrast, almost exclusively feed on larger-sized invertebrates and small vertebrates, which are usually dispatched by beating before being swallowed. Stronger biting forces as well as the characteristic prey manipulation behavior of extant rollers may account for some of the observed differences in the cranial and vertebral morphology of the fossil and extant taxa, but the exact functional correlations remain elusive. We furthermore identify a previously undescribed cranial feature of rollers: a very large foramen for the ramus occipitalis of the arteria ophthalmica externa, which is of unknown functional significance and constitutes a potentially promising research target for future studies. 相似文献
18.
Bin Bai Jin Meng Christine M. Janis Zhao‐Qun Zhang Yuan‐Qing Wang 《Ecology and evolution》2020,10(13):6333-6355
Cenozoic mammal evolution and faunal turnover are considered to have been influenced and triggered by global climate change. Teeth of large terrestrial ungulates are reliable proxies to trace long‐term climatic changes due to their morphological and physicochemical properties; however, the role of premolar molarization in ungulate evolution and related climatic change has rarely been investigated. Recently, three patterns of premolar molarization among perissodactyls have been recognized: endoprotocrista‐derived hypocone (type I); paraconule–protocone separation (type II); and metaconule‐derived pseudohypocone (type III). These three patterns of premolar molarization play an important role in perissodactyl diversity coupled with global climate change during the Cenozoic in Asia. Those groups with a relatively higher degree of premolar molarization, initiated by the formation of the hypocone, survived into Neogene, whereas those with a lesser degree of molarization, initiated by the deformation of existing ridges and cusps, went extinct by the end of the Oligocene. In addition, the hypothesis of the “Ulan Gochu Decline” is proposed here to designate the most conspicuous decrease of perissodactyl diversity that occurred in the latest middle Eocene rather than at the Eocene–Oligocene transition in Asia, as conventionally thought; this event was likely comparable to the contemporaneous post‐Uintan decline of the North American land fauna. 相似文献
19.
Humberto Astibia Xabier Pereda Suberbiola Aitor Payros Xabier Murelaga Ana Berreteaga Juan Ignacio Baceta 《Ichnos》2013,20(3-4):175-184
A rich variety of vertebrate footprints is known from a number of Upper Eocene to Lower Miocene localities of Navarre (western Pyrenees). The sediments were deposited in a wide range of depositional environments, from marginal marine to diversified terrestrial. Abundant bird tracks have been found in the coastal deposits of the Upper Eocene Liedena Sandstone of the Yesa and Itzagaondoa areas. Ciconiiformes-like (Leptoptilostipus pyrenaicus) and Charadriiformes-like (Charadriipeda ichnospp.) footprints have been recognized. Mammal ichnites have been discovered in the Oligocene and Lower Miocene deposits of Navarre. Equoid perissodactyl ichnites similar to those of Plagiolophustipus occur in the Oligocene fluviatile rocks of the Mués Sandstone of Olexoa and the Rocaforte Sandstone near Oibar and Sada. Trackways of entelodontids (Entelodontipus) are known in fluviatile-palustrine beds of the Oligocene Mués Sandstone of Olkotz. Additionally, bird (Charadriiformes-like) tracks are known in fluviatile-palustrine floodplain deposits of the Lower Miocene Ujué Formation of Los Arcos. In the same area, the Desoio and Los Arcos outcrops have also yielded perissodactyl trackways of possible Equoidea. Trackways of rhinocerotids (?) and artiodactyls (possibly Pecoripeda) are described from the Lower Miocene (Ramblian) palustrine limestones marginal to the Lerín Formation of Kaparroso and from alluvial fan deposits of the Uncastillo-Perdón Formation of Altzorritz, respectively. 相似文献
20.
Gandolfo MA Hermsen EJ Zamaloa MC Nixon KC González CC Wilf P Cúneo NR Johnson KR 《PloS one》2011,6(6):e21084
The evolutionary history of Eucalyptus and the eucalypts, the larger clade of seven genera including Eucalyptus that today have a natural distribution almost exclusively in Australasia, is poorly documented from the fossil record. Little physical evidence exists bearing on the ancient geographical distributions or morphologies of plants within the clade. Herein, we introduce fossil material of Eucalyptus from the early Eocene (ca. 51.9 Ma) Laguna del Hunco paleoflora of Chubut Province, Argentina; specimens include multiple leaves, infructescences, and dispersed capsules, several flower buds, and a single flower. Morphological similarities that relate the fossils to extant eucalypts include leaf shape, venation, and epidermal oil glands; infructescence structure; valvate capsulate fruits; and operculate flower buds. The presence of a staminophore scar on the fruits links them to Eucalyptus, and the presence of a transverse scar on the flower buds indicates a relationship to Eucalyptus subgenus Symphyomyrtus. Phylogenetic analyses of morphological data alone and combined with aligned sequence data from a prior study including 16 extant eucalypts, one outgroup, and a terminal representing the fossils indicate that the fossils are nested within Eucalyptus. These are the only illustrated Eucalyptus fossils that are definitively Eocene in age, and the only conclusively identified extant or fossil eucalypts naturally occurring outside of Australasia and adjacent Mindanao. Thus, these fossils indicate that the evolution of the eucalypt group is not constrained to a single region. Moreover, they strengthen the taxonomic connections between the Laguna del Hunco paleoflora and extant subtropical and tropical Australasia, one of the three major ecologic-geographic elements of the Laguna del Hunco paleoflora. The age and affinities of the fossils also indicate that Eucalyptus subgenus Symphyomyrtus is older than previously supposed. Paleoecological data indicate that the Patagonian Eucalyptus dominated volcanically disturbed areas adjacent to standing rainforest surrounding an Eocene caldera lake. 相似文献