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171.
A detailed assessment of postcranial fossils collected at Balouk Keui (Thrace, Greece) in the mid-19th Century by the naturalist Auguste Viquesnel enabled us to identify the material as pertaining to Palaeotherium sp., cf. P. magnum, which constitutes the easternmost occurrence of the genus during the Eocene. We have constrained the geographic and stratigraphic provenance of the fossil by reassessing information about Viquesnel's itinerary and observations. Although the exact age of the fossil remains uncertain, the occurrence of a palaeothere in the Thrace Basin during the Eocene indicates a wider geographic distribution for the genus, which had previously been restricted to western and central Europe. The palaeothere of Balouk Keui confirms that the palaeogeographic range of this group included the Balkans during the middle–late Eocene. This discovery also shows that at least intermittent land connections between western Europe, Southeast Asia, and perhaps Central Iran facilitated mammalian dispersal during the middle–late Eocene, before the famous Grande Coupure.  相似文献   
172.
A fossil species of the extant liverwort genus Frullania Raddi is described and illustrated, based on a single inclusion in a piece of Rovno amber (Ukraine) that shares its age with Late Eocene Baltic amber, its northern contemporary. Frullania rovnoi is characterised by leaves with a rounded dorsal lobe and the absence of ocelli. The ventral lobe is inflated and forms a saclike lobule, which is bell-shaped and somewhat constricted above the mouth. The bifid underleaves have several blunt teeth or angulations along the shoulder. The Rovno fossil differs sufficiently from morphologically similar species preserved in Baltic and Bitterfeld amber as to be described as new to science. The shape of the lobules and underleaves, as well as the absence of ocelli, indicate an affiliation to F. sect. Australes, hitherto represented in Eocene amber inclusions solely by F. schumannii (Casp.) Grolle. The Rovno fossil is distinguished from extant species of F. subg. Australes and from F. schumannii by having roughly and irregularly dentate-angulate underleaf margins.  相似文献   
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174.
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   

175.
报道江西临江镇晚始新世临江组内发现的含Palibinia植物群。详细记述了Palibinia属的研究历史,其地质、地理分布以及其命名问题。从其叶形态、伴生的蒸发岩以及植被的分异度等确认Palibinia为旱生植物,并对其所代表的干旱气候形成机制予以探讨。文中描述了该植物群中的6种主要植物化石,特别是对Palibinia及Nelumbo二属的代表给以较详尽的描述和讨论。  相似文献   
176.
垣曲盆地新发现的始爪兽类化石   总被引:3,自引:1,他引:2  
记述了在垣曲盆地始新世地层两个层位中发现的始爪兽科化石 3个种 ,其中包括 1个新种———周氏路南兽 (Lunaniazhouisp .nov .)。新种与属型种杨氏路南兽不同在于个体小、齿冠低、下前尖和下前脊及下斜脊更退化。  相似文献   
177.
记述了在山西省垣曲县王茅乡郭家村火石坡地点发现的原翼齿兽属一新种──童氏原翼齿兽(Dropterodon tongi sp.nov.)。新种比伊尔丁原翼齿兽(P.irdinensis)个体小、下颌联合部靠前、下前臼齿之间有齿隙、m3跟座小。新材料为垣曲盆地可能存在中始新世伊尔丁曼哈期地层提供了证据。  相似文献   
178.
179.
Summary Large limestone boulders are eroding from a landslide west of the mouth of Whiskey Creek, Clallam County, Washington State. These boulders are composed of micrite, carbonate cement, and densely-packed fossil bivalves. Siltstone in the landslide, and on the surfaces of the boulders, indicates that these limestones are derived from the lower part of the Pysht Formation. The molluscan taxa and their localised occurrence within limestone are typical features of ancient chemosymbiotic cold-seep communities. Formainiferans from both the siltstone and the limestone indicate that deposition occurred during Late Eocene time, at water depths of between 500 to 1,500 m. Lipid biomarkers, particularly isoprenoid hydrocarbons and fatty acids, with δ13C values as low as −101‰ PDB, reveal that the anaerobic oxidation of biogenic methane was an important component in the biogeochemical cycling of carbon in the ancient seep environment.  相似文献   
180.
首次记述了亚洲北大陆的犁齿鱼化石。标本采自湖北松滋县黑口洋溪组。新的标本在个体较小、最大体高位于臀鳍起点处、背鳍起点靠后、背鳍具有 1 2根鳍条、尾上骨缺失、第一末端尾椎 (U1 + 2 )上只有一根神经棘等方面显著不同于犁齿鱼属的三个已知种 (P .encaustus、P .testis和P .queenslandicus) ,代表了一新种 (松滋犁齿鱼Phareodussongziensissp .nov.)。P .encaustus和P .testis幼体的体形较长 ,为纺锤形 ,但到成体后 ,体形明显加高。P .encaustus的体长可达 5 4cm ,P .testis的可达 30cm ,而松滋犁齿鱼的体长可能只有 1 2cm ,和上述两个种的幼体差不多。但是 ,松滋犁齿鱼的体形较高 ,其轮廓和北美两个种的成体很相似 ,因此 ,虽然松滋犁齿鱼的体形较小 ,但很可能代表了成年个体。松滋犁齿鱼的体形和东南亚的Musperiaradiata(可能为Phareodus的同物异名 )比较相似。Musperia的背鳍较大、背鳍鳍条为 2 3根、背鳍起点和臀鳍起点相对、背鳍第一鳍条支持骨和臀鳍第一鳍条支持骨与同一个脊椎相连、第一末端尾椎上有两个神经棘 ,这些特征说明 ,Musperia和松滋犁齿鱼不同 ,而和北美的Phareodus的关系可能更近。  相似文献   
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