Maridet O.,Geologie und Palaontologie Abt |
Daxner-Hock G.,Rupertusstr. 16 |
Badamgarav D.,Mongolian Academy of science |
Gohlich U.B.,Geologie und Palaontologie Abt
Palaontologische Zeitschrift | Year: 2015
We report new discoveries of eomyid rodents from the Valley of Lakes (Central Mongolia) yielded by diverse layers ranging in age from the Early Oligocene (local biozone A) to the Late Miocene (local biozone E). The remains of eomyid rodents are relatively rare compared to other groups of fossil rodents found in the same region. All together, eight taxa have been identified: Eomys cf. orientalis (biozone A), Eomys aff. orientalis and Eomys sp. (biozone B), cf. Asianeomys bolligeri (biozone C), Asianeomys dangheensis (biozones C1 and D), Eomyops/Leptodontomys sp. and Keramidomys sp. (biozone D1/2), and Omboomys builstynensis gen. nov., sp. nov. (biozone E). A progressive change of dental morphology and size indicates that the genus Asianeomys represents a local evolution of the genus Eomys in Asia, but also suggests the possible existence of a lineage including Eomys cf. orientalis, Eomys aff. orientalis, cf. Asianeomys bolligeri, and Asianeomys dangheensis. © 2014, Springer-Verlag Berlin Heidelberg.
Maridet O.,Geologie und Palaontologie Abt. |
Hugueney M.,CNRS Geological Laboratory of Lyon: earth, planets and environment |
Costeur L.,Naturhistorisches Museum Basel
Swiss Journal of Geosciences | Year: 2013
The locality of Mazan (Provence, South-Eastern France) yielded numerous remains of vertebrates, including numerous isolated teeth and a few bone fragments of mammals. A preliminary faunal list was published by Triat et al; the present systematic revision of the mammalian remains and the description of new specimens reveal that the assemblage comprises 18 taxa belonging to 7 orders and 10 families. Among the mammalian remains, the theridomyids and cricetids are the two most abundant groups. This revision confirms the ascription of the locality to the biochronological unit MP21, which corresponds to the very beginning of the Oligocene. As this locality overlies the Late Eocene faunas of Mormoiron, it clearly illustrates the drastic changes induced by the European 'Grande-Coupure' in Southeastern France like in the rest of Europe. A palaeobiogeographic analysis based on a comparison with 22 other Early Oligocene localities allows deciphering the European mammalian palaeobiogeography at the beginning of the Oligocene. The mammalian assemblage of Mazan shows significant affinities with other localities from Western Europe (especially French and Spanish localities), while localities from the eastern part of Europe (Anatolian, Bavarian and Bohemian localities) are noticeably different, even though these were not subjected to strong palaeobiogeographic differentiation nor endemism. The locality of Paguera 1 (Majorca)-possibly already insular in the Early Oligocene-shows peculiar affinities with Anatolian and Bavarian localities rather than with those in Western European. This, together with the absence of strong endemism, suggests the existence of land connections with the Anatolian region, but also between the Anatolian and the Bavarian regions, permitting faunal exchanges. © 2013 Swiss Geological Society.