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A collection of approx. 150 isolated cheek teeth of the eomyid rodent Eomys antiquus which was obtained from a very thin layer in the Hamstead Member of the Bouldnor Formation at Bouldnor Cliff (Isle of Wight, England, UK) is described. The material is post-Grande Coupure, and earliest Oligocene in age. Comparison is made with and new data are given on teeth of Eomys from localities of a similar age situated elsewhere in Europe: Eomys antiquus from Hoogbutsel (Belgium), and Möhren 13, 19, and 20 (Germany), and Eomys aff. antiquus from Montalbán 1D (Spain), and Kocayarma (Turkish Thrace, Turkey). Teeth from Bouldnor Cliff and Hoogbutsel (Mammal Paleogene zone 21) are morphologically close to those from Möhren 13 (Mammal Paleogene zone 22), but tend to be larger. Size decrease in the course of time is also suggested by the smaller size of the teeth from Montalbán 1D (Mammal Paleogene zone 23). The morphological differences observed between the English, Belgian, and German material at the one side, and the Spanish and Turkish material at the other, confirm that the species from Montalbán 1D and Kocayarma is a different, although closely related form. The taxonomic history of Eomys antiquus is reviewed. The species is the commoner of the two oldest European Eomyidae known. General knowledge on the ecology of the eomyids suggests that at the time of deposition of the Eomys-containing layer in the Hampshire Basin forest was close by. [ABSTRACT FROM AUTHOR]

Mortality curves of extinct rodents can be reconstructed by using relative wear calculated from the amount of dentine exposed. MicroCT scanning of molars of the extinct Eomyid genus Ligerimys shows that this Wear Index increases gradually with wear; this means that wear classes can serve as a proxy for age and can therefore be used to reconstruct mortality curves. We reconstructed mortality curves of three species of Ligerimys from the late early Miocene of Spain. These curves show a similar trend, with decreasing numbers of molars as the amount of wear in each class increases. The curves show remarkable similarities to those of the wood mouse Apodemus. This suggests that Ligerimys was, like Apodemus, at the fast end of the fast-slow continuum, in other words r-selected, though not as extreme as some other rodents. [ABSTRACT FROM AUTHOR]

The rodent associations from the late Oligocene deposits of Ugljevik and Paragovo in the Pannonian basin are described. Pannoniamys paragovensis, a new genus and species of Spalacidae, is defined. The published data from a third late Oligocene locality in the area (Banovići) is included in the discussion of the changes in community structure through the time-interval studied. Although the composition of the rodent faunas studied differs, the dominating cricetid genus in all three associations is Deperetomys, a genus that appears in western Europe during the late middle Miocene. While the late Oligocene rodent record of central and southwestern Europe is characterised by endemic development, the regime in the Balkans seems to have been one of multiple immigrations and replacements. The late Oligocene age of the rodent fauna from Ugljevik estimated at about 26 Ma, provides a minimum age for the start of rifting in the Pannonian basin, some 6 Ma earlier than previously documented. [ABSTRACT FROM AUTHOR]

Two species of the family Eomyidae are identified in the early Miocene localities of the Araia d'Alcora outcrop (Ribesalbes-Alcora Basin, Iberian Peninsula): Ligerimys florancei and Ligerimys ellipticus. The first is rarer than the second, which is one of the most abundant mammals in the Ribesalbes-Alcora Basin assemblages. Due to its abundance, we are able to describe its variability in dental morphology, showing characteristics never previously observed, including the presence of a mesoloph or other features previously described only in ancient assemblages of this species, such as the presence of the anteroloph, which appears in younger assemblages in the Araia sequence. Furthermore, based on the eomyids, we divide the record of the Campisano Ravine section into two long local biozones, depending on the species present. In addition, each local biozone is divided into two smaller subbiozones, depending on the abundance of each species. We retrospectively compare and correlate the assemblages studied here with other Ligerimys assemblages from the other basins in the Iberian Peninsula. We classify these sites based on the abundance and species of the genus Ligerimys. Additionally, we discuss the palaeoecological preferences of these species. [ABSTRACT FROM AUTHOR]

Fossil rodents are generally scarce in the Miocene of Japan. However, as much as three taxa of eomyid rodents had been reported from the early Miocene Nakamura Formation (ca. 18.5 Ma) in Gifu Prefecture, central Japan. In this study, we revisit one of them-the small-sized taxon-and assign this material to a new genus, Japaneomys, which is so far known only from the type locality. The new genus is closely related to but distinguished from Asianeomys, which is more widely distributed in Central and East Asia, by having: (i) more bunodont cheek teeth with lower lophids, yet complete transverse lophids; (ii) two-rooted p4; (iii) anterior lobe narrower than posterior lobe on m1, correspondingly synclinid I shorter and shallower than synclinid IV; (iv) hypolophid anteriorly concave on m1. Japaneomys shows a derived but peculiar four-layered enamel microstructure with longitudinally oriented Hunter-Schreger bands, compared to three-layered microstructure in typical eomyid rodents. A phylogenetic analysis indicates that Japaneomys is more basal than Asianeomys and likely diverged in the late Oligocene when Japan was still part of the eastern margin of continental Asia, suggesting that certain small mammal populations could have undergone allopatric speciation isolated from inner-continental regions of Asia. [ABSTRACT FROM AUTHOR]

The dental material described in this paper was collected from fossiliferous ash layers of the Vogelsberg volcanic complex at Echzell, Germany. It consists of 32 teeth of a new large Apeomys species, Apeomys oldrichi n. sp., and 19 teeth of Megapeomys lindsayi Fejfar, Rummel and Tomida. Both species are extremely rare faunal elements in the early Miocene of Europe. Apeomys oldrichi n. sp. is the largest known Apeomys species, and occurs in a number of MN 3 - 4 sites in southern Germany and Czech Republic. Megapeomys lindsayi, the largest Eurasian apeomyine, was described on the basis of a single lower premolar. Herein both lower and upper cheek teeth as well as the lower deciduous premolar are described for the first time. In comparison with related populations from other localities, the evolutionary stage of the two apeomyine species clearly indicates a middle Orleanian age (MN 4) for Echzell which concurs with previous studies. http://zoobank.org/urn:lsid:zoobank.org:pub:1F9E49BE-C4B6-4597-A116-234E13D86BA9 [ABSTRACT FROM AUTHOR]

A partial skeleton of a young adult Eomyodon volkeri from the late Oligocene of Enspel (MP 28) represents the first of this genus, which was previously known only from isolated teeth at this locality. The specimen was split in two slabs upon discovery, and both parts were transferred to an artificial plastic matrix. Soft parts are preserved in the partial skeleton which comprises most of the skull with both mandibles, an incomplete vertebral column with parts of the ribcage, the right scapula with a clavicle fragment, almost the entire right forelimb (hand and left radius and ulna), parts of the pelvis and the left hind limb without the foot. It shows a generalised rodent 'bauplan'; body mass is estimated to be about 10 g based on femur length. The lengths and proportions of the phalanges indicate a terrestrial lifestyle, and the preserved soft parts do not indicate any adaptations for gliding. [ABSTRACT FROM AUTHOR]

Two species of the eomyid rodent Paradjidaumo are recognized from the Chadronian (latest Eocene) White River Formation in the Flagstaff Rim area of Wyoming: P. hansonorum from early Chadronian levels and P. nanus, new species, from higher levels representing the middle Chadronian. [ABSTRACT FROM AUTHOR]

The study of extinct Eomyid rodents represents an important segment of Burkart Engesser's scientific work. To pay tribute to Burkhard's work, this paper presents remains of Eomyops Engesser, 1979 from the German Jüngere Serie localities Kleineisenbach, Giggenhausen, Marktl, Hammerschmiede and Hillenloh. Two Eomyops species are recorded, i.e. E. oppligeri Engesser, 1990 and E. catalaunicus (Hartenberger, 1966). A third form, only found at the locality Marktl, is retained in open nomenclature. In spite of the richness of the studied material, the time gap separating the individual localities does not allow to assess precisely the relationships between the species recorded. [ABSTRACT FROM AUTHOR]

We report herein new discoveries of Gliridae and Eomyidae (Mammalia, Rodentia) from the new Early Miocene locality XJ 200604, located northwest to the Burqin city, northern Xinjiang province, China. These specimens represent three taxa of Gliridae, including a new species (Miodyromys asiamediae nov. sp., Microdyromys aff. orientalis and Eliomys? sp.), and four taxa of Eomyidae (Asianeomys aff. engesseri, Asianeomys sp., Keramidomys sp. and Eomyidae indet). The identification of two forms that are closely related to Microdyromys orientalis and Asianeomys engesseri suggests an Early Miocene age of the locality but does not allow a more precise age determination. The new discoveries of Gliridae and Eomyidae again reveal the relative scarcity of the two families in the Early Miocene of Central Asia, in contrast to the coeval rich European record. Such a discrepancy in taxonomic diversity and abundance is hypothesized as resulting from different environmental evolutions during the Early Miocene, most notably the onset of a mid-latitude dry climate in Central Asia linked to combine effects of the Tibetan Plateau uplift and the retreat of the Paratethys Sea. [ABSTRACT FROM AUTHOR]