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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.

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., This work was supported by the European Union [SYNTHESYS project, grant ES-TAF-1084]; Ministerio de Ciencia e Innovación-Agencia Estatal de Investigación; FEDER/ European Union [PGC2018-094122-B-I00].

The enamel microstructure of fossil and extant Geomyoidea (Geomyidae, Heteromyidae) lower incisors incorporates three‐ or two‐layered schmelzmusters with uniserial, transverse Hunter‐Schreger bands having parallel and perpendicular or exclusively perpendicular oriented interprismatic matrix. Phylogenetically, these schmelzmusters are regarded as moderately (enamel type 2) to highly derived (enamel type 3). Our analysis detected a zone of modified radial enamel close to the enamel–dentine junction. Modified radial enamel shows a strong phylogenetic signal within the clade Geomorpha as it is restricted to fossil and extant Geomyoidea and absent in Heliscomyidae, Florentiamyidae, and Eomyidae. This character dates back to at least the early Oligocene (early Arikareean, 29 Ma), where it occurs in entoptychine gophers. We contend that this specialized incisor enamel architecture developed as a biomechanical adaptation to regular burrowing activities including chisel‐tooth digging and a fiber‐rich diet and was probably present in the common ancestor of the clade. We regard the occurrence of modified radial enamel in lower incisors of scratch‐digging Geomyidae and Heteromyidae as the retention of a plesiomorphic character that is selectively neutral. The shared occurrence of modified radial enamel is a strong, genetically anchored argument for the close phylogenetic relationship of Geomyidae and Heteromyidae on the dental microstructure level., Incisors of fossil and extant Geomyidae (pocket gophers) and Heteromyidae (pocket mice, spiny pocket mice, kangaroo mice, kangaroo rats) show enamel with built‐in failure prevention related to chisel‐tooth digging. This distinctive microstructure character strengthens the joint phylogenetic origin of these North American rodents because it is absent in other (extinct) clades within Geomorpha (Eomyidae, Heliscomyidae, Florentiamyidae).

A new genus and species of sciuravid rodent, Perasciuravus mcintoshi, is named from the late Bridgerian (early Eocene) of the Washakie Formation, southcentral Wyoming. The most distinguishing characters of the species (and genus) are that it retains the primitive condition of the zygomasseteric structure for rodents, characteristic of sciuravids, but has a more specialized dental morphology of the cheek teeth (complete ectolophids and hypolophids on the lower molars; complete metalophs and protolophs on the upper molars) typical of the later-occurring family of geomyoid rodents, the Eomyidae. Perasciuravus is viewed as morphologically transitional between the Sciuravidae and the Eomyidae. Its occurrence also overlaps the temporal range of the Sciuravidae (Wasatchian [early Eocene] to Duchesnean [early-late Eocene]) and predates the first occurrence of the Eomyidae (Uintan [middle Eocene]).

The John Day Formation of Oregon is one of the richest and best studied assemblages in North America. Including seven members and spanning about 20 million years, there are over 150 vertebrate species known from the John Day Formation. The rodent faunas of John Day have not been as well studied as larger mammals, with many families having received little attention in the last hundred years. Here, twenty one species of rodents are described, based on new discoveries and previously unpublished specimens from the John Day Formation. The new material includes four new genera and species; the eutypomyid Allotypomys pictus, the anchitheriomyine castorid Microtheriomys brevirhinus, the eomyid Proapeomys condoni, the heteromyid Bursagnathus aterosseus; and six new species: the sciurine sciurid Miosciurus covensis, the eomyids Apeomys whistleri and Neoadjidaumo arctozophus, the heteromyids Proheteromys latidens and Trogomys oregonensis, and the sicistine dipodid Plesiosminthus fremdi. The problematical eo...

Three species of Yoderimyinae (Eomyidae: Rodentia) are recognized from the lower part of the White River Formation (early to medial Chadronian) in the Flagstaff Rim area, Wyoming. The new material allows an improved diagnosis for the subfamily. The enamel microstructure of Yoderimyinae supports its inclusion in the Eomyidae.A new genus, Zemiodontomys, is established for Yoderimys burkei Black, and new material, including upper dentition, is referred to this species. This genus differs from Yoderimys in having higher crowned and more lophodont teeth and in lacking P3. A second new genus, Litoyoderimys, is established for Yoderimys lustrorum Wood, and a new species, L. auogoleus, is referred to the genus. This genus has lower crowned, more cuspate teeth than Yoderimys.Through early and medial Chadronian time, evolution in yoderimyines includes the following morphologic transformations: increase in size; increase in crown height and lophodonty of cheek teeth; reduction of P3 (from double-rooted, to single-rooted, to absent); increase in relative size of P4 and p4; and increased longitudinal torsion of the mandible.

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.

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.

Additional specimens of the problematical rodent Pipestoneomys Donahoe, 1956, have allowed for recognition of a new family, Pipestoneomyidae. A new genus and species of pipestoneomyid is recognized from the late middle Eocene (Duchesnean North American Land Mammal Age; Bartonian), Argorheomys septendrionalis, which is morphologically more primitive than Pipestoneomys and demonstrates that this new family has been distinct since the Duchesnean. The Pipestoneomyidae share a number of derived characters with the Geomorpha, especially the two-part inner layer of incisor enamel of the Eoymidae. The Pipestoneomyidae differ from the Eomyidae in lacking the basic “omega” pattern of the cheek teeth of the former, so are in the Eomyoidea as a distinct family.

Bu çalışma, Sivas'ın kuzey doğusunda yer alan Orta-Geç Miyosen yaşlı Hafik ve İncesu formasyonlarında gerçekleştirilmiştir. Düzyayla Orta-Geç Miyosen lokalitesinden bulunan Rodentia, Lagomorpha ve Insectivora fosilleri taksonomik olarak incelenmiş ve bu fauna topluluğunun bileşimi biyokronokronolojik ve paleobiyocoğrafik olarak yorumlanmıştır. Hafik-Düzyayla lokalitesinde 11 takson tanımlanmıştır. Bu taksonlar, altısı Rodentia, (Muridae, Cricetidae, Gerbillidae, Gliridae, Sciuridae, Eomyidae), biri Lagomorpha takımından (Ochotonidae) diğeri Insectivora takımından (Soricidae) olmak üzere sekiz aileye aittir. Fauna topluluğunun göreli yaşı Rodentia ve Lagomorpha dişlerinin evrimsel aşamasına dayalı olarak çıkarılmıştır. Fauna Geç Miyosen (MN 12) olarak dikkate alınmıştır. Hafik-Düzyayla Geç Miyosen Rodentia ve Lagomorpha faunalarında geniş coğrafik dağılımları olan Avrupa ve Asya türleri baskındır., This study is occurred in İncesu and Hafik formations of Middle-Late Miocene age located in the northern of Sivas. The taxonomy of the Rodentia and Lagomorpha from the Düzyayla Middle-Late Miocene locality is studied and the composition of this assemblage is interpreted in terms of biostratigraphy and palebiogeography. Eleven species of rodents belonging to six families (Muridae, Cricetidae, Gerbillidae, Gliridae, Sciuridae, Eomyidae), one of Insectivora and one of Ochotonidae are recognised. The relative age of the assemblage is inferred on the basis of the stage-of-evolution of the rodent dentitions. The fauna is considered to be of Late Miocene age (MN 12). The Middle-Late rodent and lagomorph faunas are dominated by European and Asiatic species with large geographical ranges

The material of Eomyidae from three localities (Morteral 1, Morteral 20A and Morteral 22) of the Morteral section in the Magro Basin, eastern Spain, is described. These localities contain remains of Ligerimys and Eomyops. Morteral 1 is situated in the lowest part of the section and contains Ligerimys ellipticus, whereas Morteral 20A and Morteral 22 are situated in the middle part of the section and contain, among other rodent species, Eomyops noeliae. The youngest localities in the Morteral section (Morteral 41 and 44) record Megacricetodon collongensis, first representative of Megacricetodon in the Middle Miocene (MN5). The locality Morteral 20A contains Megacricetodon primitivus; Morteral 1 and Morteral 22 contain a form of Megacricetodon different from both M. primitivus and M. collongensis, therefore, these three localities are of lower Aragonian age (MN4). In the Aragonian type area, L. ellipticus is rare in zone B (lower part of MN4) and frequent in zone C (upper part of MN4). The first record of Eomyops in the Aragonian type area occurs in MN7/8 and in MN5 in Central Europe. The turnover of eomyid faunas in MN4 localities of the Morteral section clearly confirms the hypothesis of Engesser (1999) that Eomyops may have appeared earlier than supposed so far (MN5).

The White River Formation at Flagstaff Rim in central Wyoming is a key sequence for understanding the biochronology and chronostratigraphy of the Chadronian North American Land Mammal Age. The lower part of this section represents early Chadronian time, an interval whose fauna has not been well known. From these early Chadronian levels 15 species of rodents are discussed and/or described. Of these, three are new species, all belonging to the Eomyidae: Namatomys erythrus, Metanoiamys paradoxus, Cristadjidaumo skinneri. These rodent assemblages add substantially to our knowledge of early Chadronian faunas, and show successional changes in the rodent taxa from the earliest Chadronian through middle Chadronian.

There are 64 species of extant gliding mammals that are currently recognized, which are divided into six different families. These comprise eight species of gliding marsupials that live within Australasia and include six species of lesser gliding possums of Petaurus (family Petauridae), one species of greater glider of Petauroides (family Pseudocheiridae), and one species of feathertail glider of Acrobates (family Acrobatidae). The flying squirrels of the tribe Pteromyini within the rodent family Sciuridae represent the greatest diversity of gliding mammals, with a total of 48 species in 15 genera currently recognized, and occur throughout Asia, Europe, and North America. A second group of gliding rodents, known as the scaly-tailed flying squirrels, comprises six species from the family Anomaluridae that live in central and western Africa. The most specialized and unique of the extant gliding mammals are the enigmatic colugos, or flying lemurs, of the order Dermoptera that comprise two species and occur throughout Southeast Asia and the Philippines. In addition to the extant species there are various fossils of extinct species that are thought to have had an ability to glide, although there has been a lot of debate over most of these taxa. These fossil taxa include 3 marsupials, 18 dermopterans, 51 flying squirrels, 7 species of scaly-tailed flying squirrels, and 1 extinct species in each of the families Myoxidae, Eomyidae, and Volaticotheriidae. The taxonomic status of many living and extinct gliding mammals is still in a state of flux, and significant further revision of the taxonomic status of many groups still needs to be resolved.

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 Jungere 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.

The collection of small mammals from lacustrine sediments at �� deli hill (SW of Sivas city, Central Anatolia) contains seventeen species of rodents and two species of lagomorphs. There are four Muridae: Apodemus dominans, Occitanomys (Rhodomys) vandami nov. sp., Micromys bendai, and Muridae gen. et sp. indet., six Cricetidae: Cricetus cf. lophidens, Mesocricetus cf. primitivus, Cricetulus migratorius, Allocricetus bursae, Kowalskia sp. and Cricetidae indet., two Arvicolidae: Promimomys insuliferus and Promimomys enginae, one Gerbillidae: Pseudomeriones hansi, one Spalacidae: Spalacidae gen. et sp. indet., one Gliridae: Myomimus igdeliensis, one Sciuridae: Tamias sp., one Eomyidae: Keramidomys cf. carpathicus and two Ochotonidae: Ochotona mediterranensis, and Prolagus sp. The rodents in the fauna include a new species of murid, which is characterized by its small size (in the length/width ratio) and simple molar morphology. In this paper, I present the description of Occitanomys (Rhodomys) vandami nov. sp. The �� deli locality is assigned to the Early Pliocene / Early Ruscinian (MN 14) on the basis of the occurrence of Promimomys insuliferus in the �� deli fauna.

A new species of Eomyops, Eomyops noeliae, is described. from the locality MT-20A (Morteral section, Magro basin, eastern Spain). It is intermediate in size between the large eomiid, E. hebeiseni, and the small species of the group E. catalaunicus, E. bodvanus and E. oppligeri. The age range is Lower Aragonian. MT-20A is located between deposits that contain Megacricetodon primitivus and M. collongensis. Morphologically, E. noeliae sp. nov. is clearly different from the rest of species of the genus, due to an important reduction of the lingual anteroloph of M1,2,3 and the labial anterolophid of M3. The lower incisor shows two parallel ridges along the enamel like the type species of the genus, E. catalaunicus. This character is basic for the distinction between Eomyops and the North American genus Leptodontomys.

In this note the taxonomic position of the tiny eomyid genus Keramidomys (Hartenberger, 1967) from the Early/Middle Miocene boundary locality of Sandelzhausen in the Bavarian Upper Freshwater Molasse is reexamined. As the chronological dating of the Sandelzhausen fossil site has been modified in the past from formerly the Neogene mammal unit MN6 to now MN5 and thanks to new abundant material this rodent is compared with other European forms. It is shown that the Sandelzhausen eomyid must be called K. thaleri Hugueney & Mein, 1968 on the basis of several morphological dental differences from K. carpathicus Schaub & Zapfe, 1953. This rodent seems to be an immigrant from East Asia into Europe. Even if K. thaleri is known in many European localities, all correlated to MN5, it is always a rare element of European rodent faunas. Differentiation from K. carpathicus is not easy and requires a sufficiently large sample.

Peratherium sp. cf. P. innominatum, a species with an early Wasatchian to Duchesnean range, is present in the Turtle Basin Local Fauna. Two new genera and species of rodents are described: Cristadjidaumo mckennai (Eomyidae) and Passaliscomys priscus (Heliscomyidae). The remainder of the rodent fauna consists of species that are similar to Duchesnean faunas from both the northern Great Plains (Saskatchewan) and from southern California. The probable occurrence of Simimys and Griphomys suggests a slightly greater similarity to the fauna of southern California.

To investigate the diversity of the enamel structures in rodent molars, the schmelzmuster of more than 270 genera from the various fossil and extant groups was investigated. Only three basic types of schmelzmuster were recognized. The most prominent one, the C-type, is characterized by a basal ring of lamellar enamel (BRLE) surrounding the molars at the base of the crown. It occurs in most murids (cricetids) and other Myodonta. It is shared by the Dipodidea, Eomyidae, Geomyidae, and Gliridae. The C-type schmelzmuster was not found in any of the other rodents groups (Sciuromorpha, Anomaluromorpha, Sciuravida, Hystricognathi, Bathyergomorphi, and Caviida). Despite the rare occurrence of the P-type schmelzmuster with radial enamel only, most of these rodents have thick Hunter–Schreger bands (HSB) in their molars (S-type schmelzmuster). Although the C-type schmelzmuster is strictly limited to the Myomorpha (sensu McKenna and Bell), the fossil record shows that this structure does not form a synapomorphy but developed in parallel mostly from the P-type, but in Gliridae from the S-type schmelzmuster. On the basis of molar and incisor enamel the systematic position of Protoptychus can be evaluated.

Genus Eomys Schlosser, 1884 TYPE SPECIES. ��� Eomys zitteli Schlosser, 1884 by monotypy. REMARKS Ŋe few eomyid teeth are assigned to Eomys based on their uninterrupted mure or ectolophid, contrary to Eomyodon Engesser, 1987, Rhodanomys Dep��ret & Douxami, 1902 or Pseudotheridomys Schlosser, 1926, and on the well-marked cusps contrary to the three latter genera. Eomys aff. zitteli Schlosser, 1884 (Fig. 14 A-D) MATERIAL AND MEASUREMENTS (in mm). ��� One P4 SPV 180: 0.92 �� 0.99; one M1-2 SPV 181: 0.86 �� 1.08; one p4 SPV 185: 1.00 �� 0.89; one ml-2 SPV 184:1.04 �� 1.09; one digested lower tooth row m1-m3 SPV 183. DESCRIPTION AND DISCUSSION Ŋese isolated teeth are brachydont. P4 has a weak antesinus, a reduced anterosyncline due to the direct connection of the paracone nearly to the labial end of the anteroloph, and a short mesoloph. On M1-2, the protoloph is present and the anterosyncline longer than in P4. Ŋe mesoloph is halflong. Teeth are of greater size than those of Eomys antiquus Aymard, 1853. Ŋe size of the two molars falls into the variations of the small population of Eomys aff. zitteli from Mas-de-Pauffi�� (Comte & Vianey-Liaud 1987), the two premolars being a little smaller. Ŋe morphology of the teeth of Saint Privat-des-Vieux is also close to that seen in Eomys zitteli. A fragment of a left dentary bearing m1-3 is much damaged, pecularly m1. It belongs to a species of smaller size (notably its width) than Eomys zitteli. Ŋe measurements (m1: [0.99 �� 0.71 mm]; m2: [0.97 �� 0.90 mm]; m3: [0.81 �� 0.83 mm]) are of the same order as those of the corresponding teeth in Eomys antiquus and Eomys minor Comte & Vianey-Liaud, 1987. Ŋe occurrence of a form close to Eomys zitteli (supposed to be derived from Eomys antiquus) at Saint Privat-des-Vieux as well as at Mas-de-Pauffi��, would lead to refer this small form to another species, Eomys minor. However, the presence of a long mesolophid on m2 does not match the morphology (no mesolophids) of the type of Eomys minor. As the variability of the latter is obviously unknown, we could refer the specimen of Saint Privat-des-Vieux to Eomys minor, known in the locality Belgarric1 (Tarn-et- Garonne, MP 25) and La Blache (Maridet et al. 2010), but it could better represent an extreme variant of E. aff. zitteli . However, new eomyids were collected in Mas-de- Pauffi��:two upper teeth (M2 [0.79 �� 1.09 mm] and M3 [0.77 �� 0.98 mm]; Fig. 14E, F) can be more clearly referred to Eomys minor. Ŋeir sizes are compatible with that of the lower teeth of E. minor. Ŋe mesoloph is short on M2, and this morphology can correspond to lower molars without mesolophid; such upper teeth are also described from La Blache., Published as part of Vianey-Liaud, Monique, Comte, Bernard, Marandat, Bernard, Peign��, St��phane, Rage, Jean-Claude & Sudre, Jean, 2014, A new early Late Oligocene (MP 26) continental vertebrate fauna from Saint-Privat-des-Vieux (Al��s Basin, Gard, Southern France), pp. 565-622 in Geodiversitas 36 (4) on pages 601-602, DOI: 10.5252/g2014n4a4, http://zenodo.org/record/4538625, {"references":["ENGESSER B. 1987. - New Eomyidae, Dipodidae, and Cricetidae (Rodentia, Mammalia) of the Lower Freshwater Molasse of Switzerland and Savoy. Eclogae Geologicae Helvetiae 80: 943 - 994.","MARIDET O., HUGUENEY M. & HEISSIG K. 2010. - New data about the diversity of Early Oligocene eomyids (Mammalia, Rodentia) in Western Europe. Geodiversitas 32 (2): 221 - 254. http: // dx. doi. org / 10.5252 / g 2010 n 2 a 3"]}

International audience; Cette faune résulte de la brêve exploitation d’un petit niveau fossilifère mis au jour lors de l’ouverture d’une tranchée pour l’installation d’une conduite de gaz. Même si la quantité de sédiment fossilifère accessible était limitée, la diversité de la faune récoltée est du même ordre que celle de localités contemporaines. Parmi les 40 espèces de vertébrés reconnues, quelques unes sont amphibies mais la plupart est terrestre. Parmi elles, des marqueurs biochronologiques tel Issiodoromys pauffiensis Vianey-Liaud, 1987 (Rodentia, Theridomyidae) sont mieux définis. Cette espèce est comparée à la population type du niveau repère mammalien du Paléogène MP 26 (Mas-de-Pauffié, Lot; Chattien inférieur). De plus, des stades évolutifs jusque là inconnus sont décrits pour quelques espèces moins abondantes : c’est le cas d’un rongeur Sciuridae Comtia n. gen., d’une chauve-souris Molossidae (Cuvierimops sp.), d’un probable Talpidae, et du Hyaenodontida Thereutherium thylacodes Filhol, 1876. L’attribution familiale du serpent Platyspondylia Rage, 1974 est discutée. L’un des lézards du gisement pourrait être le plus ancien Shinisauria. La diversité de cette nouvelle faune est comparée avec celle de plusieurs faunes contemporaines (principalement Mas-de-Pauffié, Saint-Menoux, Saint-Henri/Saint-André Mümliswil-Hardberg et Oensingen 11). Le choix de Mas-de-Pauffié comme localité-type du niveau-repère MP 26 est conforté.

International audience; The Oligocene deposits of the Ulantatal area in Inner Mongolia (China) contain among the richest mammalian faunasfrom Asia. To date, only some parts of the rodent faunas have been described. Here, we propose to review the rodent faunal lists foreach site, including the description of a few new rodent specimens. We describe three additional rodent species: the CylindrodontidaeAnomoemys lohiculus, the Eomyidae Asianeomys sp., and the Dipodidae Litodonomys huangheensis. This study allows us toconstrain the stratigraphic range of Anomoemys lohiculus, which ranged from the late Early Oligocene to the early Late Oligocenein this area. Asianeomys sp. and Litodonomys huangheensis are dated from the latest Oligocene. These Oligocene deposits consistnow of more than 70 species of mammals if we include the fauna from Kekeamu. This latter corresponds to the basal part of theUlantatal Formation and could be dated biochronologically from the earliest Oligocene. When compared to the faunas from theValley of Lakes in Central Mongolia, the Ulantatal faunas present a great majority of rodents, and this difference can be partlyexplained by sampling and description biases regarding macro-mammals. This study also shows that variations existed betweenInner and Central Mongolia, especially regarding the composition of the rodent paleocommunities. However, the assessment of theirevolutionary history in this part of Asia with respect to the important climate and environment changes, require further precisionsand more material than current data allow.

A new genus of eomyid, Metanoiamys, is described from the Uintan of southern California. Two new species, M. agorus and M. marinus are also named. All Eocene species previously referred to “Namatomys” are included in Metanoiamys. Species of Metanoiamys increase in crown height and lophodonty of the cheek teeth through time, though no species lineages are recognizable. Metanoiamys represents the stem genus for the Namatomyini and possibly Eomyinae, but not for the entire Eomyidae.

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.

The oldest mammals of the Betic Cordillera are reported from the Marine-Lagoonal Formation of the internalPrebetic. Only four species were found: Blainvillimys cf. langei, Eucricetodon sp., ex group atavus, Eomys sp., and Gliravus sp. The fauna is dated as Early Oligocene. This age is in contradiction with the previously assumed Chattian age of the base of the Formation, based on benthonic foraminifera found in other localities.

Ligerimys florancei Stehlin & Schaub, 1951 (Fig. 7A, B) MATÉRIEL ET DIMENSIONS. — 1 M1 (1,26 × 1,33); 1 M3 (0,87 × 1,01) (BLQ 1 nº 2504 et 2505). DISCUSSION Ces deux molaires présentent une morphologie et des dimensions comparables à celles des populations décrites par Fahlbusch (1970) dans les gisements d’Allemagne, ainsi que celles des gisements du sud de la France (Escarguel & Aguilar 1997)., Published as part of Aguilar, Jean-Pierre, Michaux, Jacques, Bertrand, Aunay, Calvet, Marc & Lazzari, Vincent, 2010, Compléments à l'étude des rongeurs (Mammalia, Rodentia, Cricetidae, Eomyidae, Sciuridae) du gisement karstique de Blanquatère 1 (Miocène moyen, sud de la France), pp. 515-533 in Geodiversitas 32 (3) on page 526, DOI: 10.5252/g2010n3a8, http://zenodo.org/record/5381700, {"references":["FAHLBUSCH V. 1970. - Populationsverschiebungen bei tertiaren Nagetieren, eine Studie an oligozanen und miozanen Eomyidae Europas. Abhandlungen der Bayerischen Akademie der Wissenschaften, Mathematisch-naturwissenschaftliche Klasse, N. F., Munchen 145: 1 - 136.","ESCARGUEL G. & AGUILAR J. - P. 1997. - Les eomyides Pseudotheridomys et Ligerimys (Rodentia, Mammalia) du Miocene inferieur du Sud de la France. Evolution et biostratigraphie. Palaeontographica 247 (1 - 4): 25 - 58."]}