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The first finding of Mimomys in the Russian Far East

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A new species of the Mimomys is described from the Far East Russia (the Medvezhyi Klyk cave, Sikhote-Alin). Layer 7 of the Medvezhyi Klyk cave (1.08–1.18 m) was dated to be 13 790–14 200 BP. Mimomys chandolensis sp. nov. was found in a deeper layer (2.63–2.68 m) and therefore assuming there was no redeposition of the remains and that the accumulation proceeded gradually, the molar specimen we found is 30–50 kyr old. Due to the extent of the preservation we observed in the molar and the structure of the cave, the specimen does not seem likely to have been redeposited. Our hypothesis is that due to the warm and wet climate of the region, the vole, which became extinct more than 600 kyr ago, had been extant there by the Late Pleistocene period. The new species is hypsodont, with a few cement, a lack of enamel isle or prismatic fold; tangential and lamellar layers of enamel ultrastructure are poorly expressed.
The meaning, contents, and nomenclature of insect taphonomy is briefly reviewed. A combinatory system is proposed for the classification for insect trace fossils.
New diversity curves for agglutinated foraminiferal genera are presented based on the stratigraphic ranges of 764 genera distributed over the 91 Phanerozoic chronostratigraphic subdivisions given in the ICS timescale. The data set for this analysis is based on the stratigraphic ranges of agglutinated genera published in Foraminiferal Genera and their Classification, 218 of which have been modified based upon subsequently published studies and new observations. Additionally, a total of 136 genera have been newly described or reinstated subsequent to the publication of Foraminiferal Genera and their Classification. The revision of stratigraphic ranges is part of the effort by the Grzybowski Foundation’s International Working Group on Foraminiferal Classification to compile a new Catalogue of Agglutinated Foraminiferal Genera. The mean standing diversity of agglutinated foraminiferal genera was compiled by counting the number of boundary crossers rather than the number of genera in each stage. This diversity curve displays a general upward trend throughout the Phanerozoic, punctuated by peaks and troughs of variable magnitude. The curve shows a period of initial radiation from the Early Cambrian to the Early Silurian, followed by a plateau to the Late Permian. The Permian/Triassic and the Triassic/Jurassic boundaries are characterised by small dips in the diversity record. The Jurassic begins with an exponential rise in mean standing diversity that continues to the Cenomanian. The Cenomanian to Holocene record of mean standing diversity is characterised by four peaks and troughs that are roughly in line with the cycles of global climate, with reductions in diversity in the end−Cenomanian, end−Cretaceous, and end−Miocene. Excluding modern values, the Phanerozoic maximum in the number of genera with a fossil record is observed in the Cenomanian, whereas the maximum Phanerozoic mean standing diversity is observed in the Langhian stage of the Miocene. The highest per−capita origination rates are observed in the Hettangian, Dapingian, Pleistocene, and Sheinwoodian (mid−Silurian). Linear regression analysis of the origination rates reveals a decrease towards the Holocene, in agreement with findings of Raup and Sepkoski. The highest per−capita extinction rates are observed in the Messinian, late Silurian (Gorstian), Hirnantian (latest Ordovician), and Maastrichtian. The background extinction rate shows an increasing trend towards the Recent, which is in disagreement with the findings of Raup and Sepkoski. We attribute this apparent discrepancy to the Late Cretaceous to Palaeogene extinctions of shallower−water larger agglutinates and the pull of the end−Miocene extinction event.
In a letter to Nature (February, 2011), Xunlai Yuan and col− laborators recorded carbon compression fossils from black shales of the Lantian Formation (Ediacaran), southern Anhui Province, South China. The new fossils, described under five morphological types (Types A to E), exhibit de− grees of morphological differentiation suggesting that they were multicellular eukaryotes. Some of the Lantian macro− fossils were interpreted as algae, but others are of unknown affinities. For reasons noted in this discussion, Type A fossils attracted our particular attention, and we suggest an alter− native interpretation of their affinities. According to our view, some of them (at least those with three faces and no globose holdfast at their base) may represent conulariid cni− darians or close medusozoan relatives. The undistorted or− ganism probably was a three−sided cone in life. We believe that our suggested alternative interpretations of the anat− omy and affinities of the fossils in question can be useful in guiding future research on the oldest currently known fossil assemblage of multicellular organisms.
Coccolith debris in fossil zooplankton faecal pellets and the mode of its preservation are the unique source of data on the mode of feeding and digestion by ancient zooplankters. The animals are virtually absent in the fossil record in another form than their coprolites. However, minute structural details of coccospheres and their debris in the coccolith limestone are much less legible than in modern sediments. This paper presents how clear SEM images of details of coccolith plates in complete and dismembered coccospheres from fossil zooplankton faecal pellets can be obtained from thin sections of coccolith limestone. The images allow us to study the structural and compositional details of coccolith plates as well as their arrangements within the coccospheres and fossil faecal pellets.
In a small piece of Baltic amber several poorly preserved amphipod crustaceans were found. The most probable seems to be the affinity of these amphipods to the freshwater family Crangonyctidae.
The history and scope of the collection of inclusions in Baltic amber of the Muséum d’histoire naturelle Neuchâtel (MHNN) is briefly outlined. Diptera are largely dominant, with some 4600 specimens belonging to 38 families, some of which are of rare or very rare occurrence in Baltic amber. A table summarizing the families represented in the collection and including the number of specimens of each of them is provided.
The faunal history of insects in the various fragments of Gondwana is presented. The first part of the paper summarizes the current knowledge of its insect-bearing localities, particularly their stratigraphy and fossil content, emphasizing the record of the higher systematic groups. The second part discusses some trends of their palaeobiodiversity as evidenced from the above mentioned sites. Generally, the knowledge of the fossil Gondwanan insect faunae is still much lower than that of the Laurasian ones, but has considerably increased over the last decade. Altogether about 85 localities are known from Gondwana, with a maximum of sites in Permian and a minimum in Jurassic times. Best represented is South America. Fossil insects of Gondwana are probably less known than those of Laurasia due to inadequate exploration rather than unfavourable conditions for the formation of deposits.
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