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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 aim of the work was to determine which part of biomass remains in the forest in the form of so-called logging residue. In order to achieve the result, the analysis of wood volume harvested in the final felling was carried out, and the total volume was broken down into different parts of trees. Furthermore, to estimate the wood volume of the forest stand, on each of the experimental plots 10 model trees were chosen based on Draudt method. Assuming that the thickness of wood acquired from forest is bigger than 4 cm, it is possible to assume that the part of biomass which remains in the forest in the form of the branches and conifer needles ranges from 10% to 12% of general amount of biomass.
The cephalopods of the subclass Orthoceratoidea, which are termed “orthoceratoids” herein, are a group that remains “the last unexplored wilderness in the Cephalopoda” (Flower 1962: 23). After 45 years this statement still holds true because phylogeny reconstructions are hindered by their morphological simplicity, numerous homeomorphies and iterative evolution. The Orthocerida, straight cephalopods that are characterised by a wide chamber spacing, a thin tubular siphuncle and a small spherical initial chamber, lacking a cicatrix (Kröger 2006) were the ancestors of bactritoids, ammonoids, and coleoids (Engeser 1996). The origin of the Orthocerida is poorly understood. The earliest unequivocal Orthocerida are known from the Floian (Early Ordovician). A number of poorly known possible Orthocerida and/or stem group Orthocerida are known from the Tremadocian. Here, I reassign the long known middle Tremadocian “Orthoceras attavus” to the new genus Slemmestadoceras belonging to a group of worldwide distributed orthoceratoids. The presence of Slemmestadoceras with a thin, probable tubular siphuncle and small initial chambers in the middle Tremadocian suggests that the Orthocerida may have originated already at that time. The comparison of Slemmestadoceras with following late Tremadocian and Floian orthoceratoids demonstrates that a higher level taxon comprising these forms, such as the subclass Orthoceratoidea may constitute a paraphylum.
The ability to see and understand the three−dimensional structure of an investigated object plays a key role in studying fossil remains. All living organisms are formed in threedimensions, but unfortunately fossilization processes often reduce overall shape, making it difficult to gather information about real overall appearance, functionality, and inner structure. Here, using a specimen of the brachiopod Terebratula terebratula we demonstrate a non−destructive technique for exploring the 3−D internal structure of fossil remains. The use of tomography allows the construction of a set of transverse serial sections in the manner used by brachiopod researchers for decades.
seventeen early medieval sedimentary layers of the port of the town of Wolin, corresponding chronologically with the time period from the beginning of the 9th till the middle of the 13th century, the occurrence of 3 537 bone remains was stated, of which 2 784 pieces had their anatomy determined. In the identified archaeological material 33 types of bones were found, belonging to 15 species of teleost fishes, as well as 4 kinds of common sturgeon remains (Acipenser sturio). The bones of viscerocranium, mainly of zander (Stizostedion lucioperca), bream (Abramis brama), and perch (Perca fluviatilis), were dominant (57.23%).
230 bird bones representing at least 36 taxa were found among the 129 300 remains accumulated in the fishing camp Dudka between the years BP 11,200 and 3,800. Most of the birds belonged to water-and-marsh species. Mergus albellus, Tadorna tadorna and cf. Nycticorax nycticorax are species new to the subfossil fauna of Poland. Most of the bird bones are dated to the Paraneolithic Zedmar culture and the Neolithic of the late Atlantic and the early Subboreal period (5,600 – 3,800 BP). Bones of the pectoral girdle made up 76% of the identified remains. The archaeological context indicates that the birds were hunted by people inhabiting the island; most of the species belong to game. The absence of Lagopus remains is noteworthy. Ten bones were recovered from graves and two were found as polished beads, this indicating that birds were used not only for food.
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The fossil remains of a hemichordate exoskeleton, recognized as fragments of the stolons and their cyst−like swellings connected with the fusellar zooidal tubes, were derived by chemical isolations from Late Permian (Kazanian) mudstones of the Svalis Dome (central Barents Sea, Norway). These fossils, referred to as Diplohydra szaniawskii sp. nov., are the first undoubted representatives of the class Graptolithoidea found in Permian deposits. The genus Diplohydra Kozłowski, 1959, known previously only from the Ordovician and originally established as a thecate hydroid taxon, is reinterpreted as an aberrant member of the order Rhabdopleuroidea. This strange hemichordate, characterized by fusellar tubes distinctly narrower than stolon−like tubes and their swellings, reveals a certain degree of dimorphism in the stolon system. D. szaniawskii sp. nov. also displays some peculiar morphological features common to the Ordovician rhabdopleuroid genus Rhabdopleurites Kozłowski and the stolonoid genus Stolonodendrum Kozłowski.
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Tapirs from the Pleistocene of Venezuela

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The living tapir Tapirus terrestrisis widely distributed in Venezuela, occurring mainly south of the Orinoco, while being absent from arid, high Andean and insular areas. Here, we describe new material of fossil tapirs from two Pleistocene localities of Venezuela: Zumbador Cave and El Breal de Orocual. Based on its size and morphology, the material from Zumbador Cave (skull, mandible and postcrania) is assigned to the extant T. terrestris, and represents the most northwestern fossil record of this species in South America. By contrast, the remains from the tar seep of El Breal de Orocual are more gracile, and differ from T. terrestris and other fossil and living species from South America in the presence of a metastylid on the lower cheek teeth. We tentatively assign the latter remains to Tapirussp., based on juvenile and isolated dentary material. However, the possibility that these specimens may represent a new species or an immigrant from North America cannot be completely excluded.
Penguin bones from the La Meseta Formation (Seymour Island, Antarctic Peninsula) are the only record of Eocene Antarctic Sphenisciformes. Being an abundant component of the youngest unit of the formation (Telm7), they are not so common in earlier strata. Here, I present the oldest penguin remains from the La Meseta Formation (Telm1-Telm2), often bearing close resemblance to their counterparts from younger units. Addressing the recent findings in fossil penguin systematics, I suggest there is too weak a basis for erecting new Eocene Antarctic taxa based on non-tarsometatarsal elements of penguin skeletons, and considering Oligocene species part of the studied assemblage. Finally, I conclude if the common ancestor of extant Sphenisciformes lived in the Eocene Antarctic (as suggested recently), penguins referred to Delphinornis seem to be prime candidates to that position.
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