Lower Serpukhovian (Steshevian) foraminifers and algae from exotic limestone clasts of Nötsch (Eastern Alps,Austria)

The > 1,000 m-thick Carboniferous sedimentary succession of Nötsch is divided into the Erlachgraben, Badstub, and Nötsch formations with poorly constrained precise ages, but probably constituting a continuous lithostratigraphic Group deposited from the latest Viséan to the early Bashkirian, thus including a complete Serpukhovian succession. We date the early Serpukhovian (Steshevian) in exotic limestone clasts of the Badstub Fm. based on algae and foraminifers. These limestone clasts have been reworked from a carbonate shelf, indicating that they are older than the Badstub Fm. Microfacies and fossil assemblages indicate that a shallow marine carbonate shelf was developed at the northern margin of the deep-sea basin of Nötsch. The assemblages include the red alga Hortonella, rare green algae, and incertae sedis algae Praedonezella, Aoujgalia, and Frustulata; howchiniid and lasiodiscid foraminifers; atypical endothyrids, probably belonging to Semiendothyra emend.; rare Janischewskina; taxonomically disputable eostaffellids (including Eostaffellina aff. paraprotvae) and pseudoendothyrids; attached forms transitional between pseudolituotubid Fusulinata and calcivertellid Miliolata; and probably the oldest known free Miliolata. Newly described taxa include the incertae sedis algae Praedonezella sebbarae nov. sp. and the foraminifers Pseudoendotaxis nov. gen., Quasilituotuba serpens nov. sp., Q. pseudospiroides nov. sp., and Eoglomospiroides carnica nov. sp. Revised foraminiferal taxa include Pseudolituotubidae, Quasilituotuba cf. serpuchoviensis nov. comb., and Q. ex gr. extensa nov. comb. The studied material provides information about the phylogeny of the first Miliolata and permits the reconstruction of the lineage of Pseudolituotubidae and Calcivertellidae, between the classes Fusulinata and Miliolata. The palaeobiogeography of Austria during the Serpukhovian is not yet clearly established, but relationships with the Saharan and Mediterranean Provinces exist, and especially with the Donbass. Fewer relationships are conspicuous with England, the Moscow Basin or the Urals.     

Biostratigraphical precisions on the Early Serpukhovian (Late Mississippian), by means of a carbonate algal microflora (cyanobacteria, algae and pseudo-algae) from La Serre (Montagne Noire, France)

The microbial-dominated part of a Late Mississippian (Early Carboniferous) carbonate olistolite at La Serre (Montagne Noire, southern France) yielded interesting algae and pseudo-algae. The constituents are well known cyanobacteria (not described) and different representatives of poorly known or new species: cyanobacteria: Aphralysia capriorae, Hedstroemia (?) serrana n. sp., Dasycladales: Paraepimastopora sp., Nanopora sp., Cabrieropora pokornyi and E. occitanica, Anatoliporaceae: Richella incrustata, Caulerpales: Poncetellina (?) sp., questionable Archaeolithophyllaceae: Hortonella sp., Archaeolithophyllaceae: Neoprincipia with Neopricipia fluegeli, Neoprincipia petschoriaeformis n. sp., Neoprincipia claviformis n. sp. and Archaeolithophyllum ex gr. lamellosum; pseudo-algae Aoujgaliida: Stacheoidella spissa, Ungdarella uralica, and Fasciellidae: Fasciella and Praedonezella, with both polymorph species: Fasciella kizilia, and Praedonezella ex gr. cespeformis. This carbonate microflora is dated as Early Serpukhovian (Pendleian) by its association with the foraminifera Janichewskina, “Biseriella” and “Warnantella”. This dating is confirmed by the little more advanced algal assemblage, compared to the Latest Visean (Brigantian) assemblages from Montagne Noire (e.g. Japhet, Castelsec), and more primitive than the Late Serpukhovian (Arnsbergian) of Ardengost (Pyrenees). The importance of the calcifoliid pseudo-algae—Fasciella, Praedonezella, and Calcifolium (although this latter is locally lacking)—is suggested for the biozonation of the Visean/Serpukhovian boundary.     

Neoprincipia nov. gen., a new Mississippian red alga, and remarks on the Archaeolithophyllaceae (Rhodophyta)

A new alga is described from the late Visean of SW Spain: Neoprincipia nov. gen. Specimens of this new genus were either usually assigned to Archaeolithophyllum or Principia of Brigantian-Serpukhovian age. Two new species N. guadiatica nov. gen., nov. sp. and N. tethysiana nov. gen., nov. sp. are described. Their massive appearance, in continuous series, characterizes the base of the Brigantian elsewhere in the Paleotethys, although some rare cases of first appearance in the late Asbian exist. Its acme is Brigantian, but it extends into the Pendleian. The genus Neoprincipia, and its family Archaeolithophyllaceae, are interpreted to be the earliest true red algae, that exhibit clearly differentiated hypothallus and perithallus, and therefore are situated at the origin of these “coralline algae”, which are very prolific from the Cretaceous to the Recent.     

New data on the phylogeny of Choristitidae (Carboniferous brachiopods)

A new species and genus of Choristitinae, Adventochoristites abavus gen. et sp. nov., is described from the Upper Serpukhovian of the Donets Basin and is considered as an ancestor of the Middle-Late Carboniferous Choristites linage. The characteristic features differing Alphachoristites from Choristites and Trautscholdia are specified. New species Alphachoristites berestovensis sp. nov. and Quizhouspirifer tshaikensis sp. nov. are established.     

Rugose corals and associated carbonate microfossils from the Brigantian (Mississippian) of Castelsec (Montagne Noire, southern France)

The disused quarry east of Castelsec offers a view of shallow-marine carbonates of the poorly known Uppermost Mississippian of the Montagne Noire. At Castelsec, sections are studied in two characteristic facies types (bioclastic wackestone and microbial dominated boundstone) of the Upper Mississippian. The succession is rich in rugose corals and carbonate microfossils. Six genera with seven species belonging to a rugose coral fauna consisting of at least eight genera with several species are described herein; Dibunophyllum castelsecensis sp. nov. is described as new. Twenty-seven carbonate microfossils of different groups have been identified. The Castelsec succession is Brigantian in age, based on the stratigraphic occurrence of rugose corals, foraminifers, and calcareous algae observed in both sections. The rugose coral fauna shows relationships with the well-known fauna of northwestern Europe and the Ouralian-Asian Province. Typical elements of northwestern Europe are missing at Castelsec and vice versa. This differentiation between north and south is interpreted as responses to different palaeolatitudes and tectonic settings.     

New species of spiriferids (Brachiopoda) from the Devonian and Carboniferous of Eastern Europe

In a revision of previously published materials, two new spiriferid species from the Late Tournaisian, Unispirifer subtornacensis sp. nov. and Mesochorispira ussuilensis sp. nov., and Atylephorus nalivkini sp. nov. from the Lytva Horizon of the Upper Devonian of Bashkiria are described. Based on the original collection, a new Serpukhovian subspecies, Podtsheremia duplicicosta triplicicosta, from the southern Ural Mountains and a new Late Carboniferous species, Purdonella kalashnikovi, from the polar Ural Mountains and adjacent islands are established.     

Les brachiopodes carbonifères des Pyrénées centrales françaises: 2: Étude des Orthida et des Spiriferida; biostratigraphie,paléoécologie,paléobiogéographie

This paper follows the first part: Legrand-Blain &alii, 1983,Geobios, n^o 16, fasc. 3.The brachiopods here described from the «Culm are: Schizophoria cf. resupinata, Rhipidomella michelini, Actinoconchus aff. paradoxus, Lamellosathyris gr. lamellosa, Cleiothyridina (Leiothycridina) nov. sp. gr. okensis, Podtsheremia (s.l.) convenarum nov. sp., Neospirifer gr. derjawini, Anthracospirifer (?) sp., Brachythyrina (Anthracothyrina) perextensa nov. subgen., nov. sp., «Spirifer lujkiensis, Zaissania nov. sp., Kitakamithyris or Torynifer (?) sp., Martinia minima. From shales associated with the Ardengost limestones, slightly different faunas are: Podtsheremia (s.l.) convenarum (?), Anthracospirifer (?) sp., Brachythyrina (Anthracothyrina) bressoni nov. subgen., nov. sp., Phricodothyris mosquensis, Martinia buckmani.The brachiopods from Ardengost limestones andassociated shales, well dated, are of upper Serpukhovian age. The «Culm ones might be heterochroneous, with Serpukhovian and (?) Bashkirian elements. The paleoecology of the brachiopods from limestones and associated shales indicates moderate and low energy environments. The «Culm brachiopods display both resedimentation and delicate preservation features. There is evidence of rather close palaeobiogeographic relationships with the northern Sahara: during the late Serpukhovian, a «Sahara-Pyrénées region could be distinguished, at the western part of the vast Tethysian province.     

Late Viséan–Serpukhovian foraminifers in the Montagne Noire (France): Biostratigraphic revision and correlation with the Russian substages

The “calcaires à Productus” of the Montagne Noire (Aude-Hérault, southern France) are carbonate lenses embedded within a thick Carboniferous siliciclastic complex. Foraminiferal assemblages in some of the larger carbonate lenses are typically representative of the late Viséan and Serpukhovian. Eleven new species of foraminifers are described: Hemidiscopsis variabilis, H. pilleae, Planohowchinia rara, P. redondensis, Spireitlina minima, Rectoendothyra japhetensis, Mikhailovella enormis, Cribrospira? perretae, Pojarkovella occidentalis, Parabiseriella vailhanensis, and Biseriella delicata. Eight foraminiferal biozones are defined; they are based on the first occurrence of some taxa, and could be used for other regions of southern France (e.g., Mouthoumet and the Pyrenees). These biozones are informally named as A to H. Due to the problems with classical biozonations and substages in northern England as well as Belgium and northern France, the biozones established herein are mostly compared with the Russian standard substages. Thus, biozones A and B are correlated with the Mikhailovian, corresponding to the latest Asbian and earliest Brigantian in western Europe; biozones C, D and E are correlated with the Venevian, equivalent to the upper part of the early Brigantian in western Europe. Therefore, biozones A–E form part of the late and latest Viséan. The stratigraphically younger biozones F, G and H contain foraminiferal assemblages correlated with the Tarusian, Steshevian and Protvian, respectively.     

Lower Carboniferous (middle Visean) foraminifers and algae from an interior sea,Southern Carnarvon Basin,Australia

A moderate diversity biota of foraminifers, algae and calcareous microproblematica is recorded from the Lower Carboniferous Yindagindy Formation within the intracratonic Southern Carnarvon Basin in Western Australia. Very shallow metahaline to hypersaline conditions are suggested. The palaeobotanical components are sporadic calcitarcha, tuberitinaceans, codiaceans Orthriosiphon? sp. 1, dasycladaleans? Koninckopora tenuiramosa, and algosponges Issinella devonica, Serrisinella cf. serrensis, Issinella? sp. 1, Kamaena cf. awirsi, Proninella? sp. and Stacheoides spp. The foraminiferal assemblage is dominated by a new koktjubinid taxon: Praekoktjubina yindagindyensis nov. gen., nov. sp. Subordinate associated foraminifers are more sporadic Salpingothurammina? sp. 1, Plectinopsis michelseni nov. gen., nov. sp., Rectopravina multifida nov. gen., nov. sp. (with 4 morphotypes), and scarce Endothyra spp. Despite many of these taxa being endemic, a middle Visean age is probable, based on: (1) the maximum global geographic extent of K. tenuiramosa reached during the middle Visean, (2) the disappearance of Plectinopsis nov. gen. in Palaeotethys and the Urals, and (3) the first occurrence of Praekoktjubina nov. gen. in Palaeotethys. An age no older than the middle Visean is supported by sparse conodonts from the Formation and comparison to episodes of carbonate deposition in the Bonaparte Basin, further north in the East Gondwana rift system. Absence of middle Visean archaediscoids may be due to high salinity. The following algal and foraminiferal families and superfamilies are emended: Scribroporellaceae (a lectotype is selected for Orthriosiphon saskatchewanense); Palaeospiroplectamminidae (due to the creation of Plectinopsis nov. gen.); Haplophragminoidea (due to the creation of Rectopravina nov. gen.); and Globivalvulinoidea and Koktjubinidae (due to the creation of Praekoktjubina nov. gen.).     

Discosorids and Oncocerids (Cephalopoda) of the Middle Ordovician Kunda and Aseri Regional Stages of Baltoscandia and the early evolution of these groups

Discosorid and oncocerid cephalopods of the Kunda and Aseri Regional Stage (Darriwilian, Middle Ordovician) from Öland Island, Sweden and North Estonia are described for the first time. We demonstrate that a high generic and specific diversity of Oncocerida was already established in the earliest Darriwilian. The new oncocerid species Neumatoceras borense nov. sp., N. breviborense nov. sp., Paramiamoceras breviventrum nov. sp., Richardsonoceras gastroscopium nov. sp., R. gerhardi nov. sp., R. goldmanni nov. sp., R. haelluddenense nov. sp., Richardsonoceroides kingi nov. sp., R. oelandense nov. sp., and R. rhytium nov. sp. are erected; Richardsonoceroides schiefferdeckeri (Dewitz) is revised. The new graciloceratid Kundoceras evansi nov. gen., nov. sp. is erected. A review of records of early oncocerids from China shows that Richardsonoceras Foerste is probably the most primitive oncocerid and supports the hypothesis that oncocerids evolved in the early Floian or latest Tremadocian from a Bassleroceras Ulrich and Foerste-like ancestor. The new discosorid genus Paldoceras nov. gen. and species Paldoceras paldiskense nov. sp. and P. neptunsakerense nov. sp. are erected. These discosorids record the morphological link between the late Darriwilian Ruedemannoceras Flower and the early Floian Apocrinoceras Teichert and Glenister, which is considered to be the earliest discosorid.     

New latest Permian foraminifers from Laren (Guangxi Province, South China): Palaeobiogeographic implications

Microfacies analyses performed on the latest Permian Wujiaping Formation at Laren (Guangxi Province, South China) show that the bioclastic-rich limestones of Late Permian age contain a rich and well-diversified foraminiferal fauna. This fauna is here revised in order to be compared with time-equivalent levels of southern Iran and southern Turkey. Some new and unexpected phylogenetic trends are highlighted among the biseriamminoids. The new or poorly known genera Retroseptellina, Septoglobivalvulina, Paraglobivalvulinoides, Dagmarita?, Bidagmarita nov. gen., Louisettita, Paradagmaritopsis nov. gen. and Paradagmarita? are concerned. Nevertheless, these newly appeared biseriamminoids are subordinate to abundant Tetrataxis and Climacammina, ultimate survivors of the families Palaeotextulariidae and Tetrataxidae, appeared as old as the Early Carboniferous (“Mississippian”). Algae, miliolids, and nodosarioids are poorly represented. Two genera and four species are here newly described: Globivalvulina curiosa nov. sp., Louisettita ultima nov. sp., Bidagmarita nov. gen., Bidagmarita sinica nov. gen. nov. sp., Paradagmaritopsis nov. gen., Paradagmaritopsis kobayashii nov. gen. nov. sp. The palaeogeographic distribution of these foraminifers is interpreted to be typically of Neo-Tethyan regions, ranging from southern Turkey (Hazro) to South China (Laren) and up to Japan for some species (i.e., Paradagmaritopsis). At Laren, Late Permian strata are generally characterized by Reichelina ex gr. simplex Sheng. Isolated samples of packstones, collected in Tsoteng region (Guangxi Province, South China), contain Sphaerulina sp. together with various smaller foraminifers and numerous representatives of the new species G. curiosa nov. sp. In this study we demonstrate that the regions of Zagros (Iran), Taurus (Turkey), South China and even Japan shared similar foraminiferal assemblages and represented intermittently connected palaeobiogeographic provinces during Late Permian times.     

A new species of Cribroconcha (Ostracoda) from the Serpukhovian of the Southern Urals

A new ostracode species, Cribroconcha magna sp. nov., is described from the Serpukhovian cephalopod facies, Lower Carboniferous, of the Southern Urals. The ostracodes particularly frequently co-occurring with the index species are shown in the plate. The localities of the new species are described.     

Systematics and taphonomy of an Early Kimmeridgian belemnite fauna from the Mediterranean Tethys (Monte Nerone, Central Apennines, Italy)

About three hundred belemnite rostra were collected from Lower Kimmeridgian beds of a structural high sequence cropping out at Mt. Nerone (central Apennines, Pesaro Province, Italy). The belemnite fauna is composed mainly of new species. Nine species were recognised, ascribed to five genera, which include Hibolithes semisulcatusMünster, 1830; H. pignattii nov. sp.; Acutibelu0s sp. cf. acuariformisRiegraf, 1981; Belemnopsis neronensis nov. sp., Duvalia matteuccii nov. sp., D. nicosiai nov. sp., D. pallinii nov. sp., D. raymondi nov. sp. and Rhopaloteuthis massimoi nov. sp.; moreover a single specimen is treated in open nomenclature as Belemnopseidae incertae sedis. The stratigraphic and palaeobiogeographic significance of the new fauna is discussed. The taphonomy of the belemnite-rich level is described, with reference to borings found on the belemnite rostra.La fauna a belemniti risulta composta quasi esclusivamente da specie nuove. Sono state riconosciute le seguenti specie: Hibolithes semisulcatusMünster, 1830; H. pignattii nov. sp.; Acutibelus sp. cf. acuariformisRiegraf, 1981, Belemnopsis neronensis nov. sp., Duvalia matteuccii nov. sp., D. nicosiai nov. sp., D. pallinii nov. sp., D. raymondi nov. sp. and Rhopaloteuthis massimoi nov. sp. Inoltre un esemplare è stato discusso con nomenclatura aperta come Belemnopseidae incertae sedis. Alcuni nuovi dati stratigrafici e paleobiogeografici sono stati analizzati ed integrati con i dati della letteratura. E’ stata anche esaminata la tafonomia del livello a belemniti e le perforazioni presenti sulla superficie dei rostri.     

Late Viséan (MFZ14) foraminifers and algae from the Kirchbach Limestone (Carnic Alps,Austria) and geological implications

The Kirchbach Limestone occurs in the middle part of the early Viséan to Bashkirian Hochwipfel Formation, which was deposited in a flysch basin that formed during an extensional rifting phase in the foreland of the Noric Terrane, was filled with deep-marine synorogenic sediments and closed during the Bashkirian. The Noric Terrane split off from Gondwana and drifted towards the north, closing the flysch basin, which was part of the Paleo-Tethys. The Kirchbach Limestone is composed of bioclastic mudstone and carbonate conglomerate. Microfacies of the limestone clasts include wackestone, packstone, grainstone, and rudstone with diverse fossil assemblages. Bindstone clasts are derived from very shallow, restricted environments. Other clasts are bioclastic mudstone derived from deeper settings. All the foraminifers and algae identified correspond to the upper MFZ14 biozone, after the appearance of Bradyina; in contrast, the markers of the uppermost MFZ14 (Asteroarchaediscus, Loeblichia paraammonoides, and Warnantella) and those of MFZ15 (Janischewskina, Climacammina, and Biseriella) are totally absent. The Kirchbach markers are Cribrospira mikhailovi, Bradyina cf. flosculus, Howchinia bradyana, and Eostaffella parastruvei. Revised local taxa are Mstinia, M. minima n. comb., Consobrinellopsis n. gen., and C. ex gr. consobrina n. comb. The Kirchbach Limestone is derived from a shelf area displaying various shallow-water environments from which the clasts were transported into deeper-marine environments as sediment gravity flows. Limestone clasts of the Kirchbach Limestone indicate the presence of a shallow carbonate shelf along the northern margin of the Hochwipfel flysch basin. The late Asbian (MFZ14) limestone clasts derived from this carbonate shelf were probably subaerially exposed prior to their reworking and redeposition within the flysch sediments, which are late Brigantian (MFZ15) in age. Fossiliferous carbonate shelf sediments of Viséan–Serpukhovian (Namurian) age in the Veitsch Nappe of the eastern Graywacke Zone may be remnants of this shelf. Similar trilobite faunas of Nötsch and Veitsch indicate that they were originally adjacent and probably connected to this shelf north of the flysch basin. These data confirm that the Carnic Alps were located in the Viséan Mediterranean subprovince.     

Alilepus meini nov. sp. (Leporidae,Lagomorpha) from the Early Messinian of Tuscany (central-western Italy)

Alilepus meini nov. sp., a new leporid known only from the Early Messinian of central-western Italy (Baccinello-Cinigiano basin, V3 faunal assemblage; Tuscany), is described here. A. meini nov. sp. is an endemic taxon – not inherited from the older Tusco-Sardinian assemblages – of the continental and balanced BCB V3 fauna. The peculiarities of A. meini nov. sp. mainly reside in the occlusal surface of p3 (very large anteroconid, extremely short talonid, deep and crenulated posterior flexids, extremely thin protoisthmus) and P3 (wide hypoflexus). A. meini nov. sp. seems closely related to Alilepus turolensis, as testified by shared morphological characters (globous anteroconid and deep protoflexid, very thin protoisthmus). Palaeobiogeographical evidences support morphological data as A. meini nov. sp. and A. turolensis are the only two species of the genus present in western Europe.     

A new species of Late Pleistocene rail (Aves: Rallidae) from Abaco, the Bahamas

We describe a new species of rail from the Sawmill Sink blue hole on Abaco Island in the northern Bahamas. Known from abundant, beautifully preserved Late Pleistocene fossils, Rallus cyanocavi sp. nov. was a medium-sized, flightless species that probably was endemic to the Little Bahama Bank, which is a carbonate platform surrounded by deeper water. We are uncertain whether R. cyanocavi survived into the Holocene, when higher sea levels transformed the Little Bahama Bank from a single large, Late Pleistocene island (ca. 12000 km²) to the scattering of smaller islands seen today, the largest of which is Abaco (1681 km²). Fossils of additional extinct, flightless species of Rallus probably await discovery on some of the 21 other carbonate banks that span the Bahamian Archipelago.     

New Late Viséan and Early Serpukhovian ammonoids in the Verkhnyaya Kardailovka section (Eastern Slope of the South Urals)

New Late Viséan and Early Serpukhovian ammonoids are described from the Verkhnyaya Kardailovka section (South Urals, Bashkortostan). The ammonoid assemblages allow the recognition of the Hypergoniatites?Ferganoceras Genozone and a correlation with the synchronous zonations of North Africa, Spain, and China. The new species Ferganoceras constrictum sp. nov., Dombarites clemens sp. nov., and Hypergoniatites kardailovkensis sp. nov. are described.     

Intraspecific variation in Triassic Ophthalmidiid Foraminifera from Timor

Four ophthalmidiid species are described as free specimens extracted from mudstones and wackestones of Triassic age: Atsabella bandeiraensis nov. gen. nov. sp., Karaburunia atsabensis nov. sp., Ophthalmidium sp. cf. O. primitivum Ho and Spirophthalmidium grunaui nov. sp. Analysis of morphological variation found in large suites of specimens suggests that, as in modern miliolids, apertural characteristics, chamber shape and adult test size are features that vary within narrow limits and may be used to define species. In genera with milioline coiling in the post-embryonic stage, chamber arrangement may be highly variable. Post-embryonic coiling in K. atsabensis varies from quinqueloculine to almost spiroloculine and encompasses morphotypes that, in thin-section studies, have been attributed to a number of other genera. In Timor Leste, A. bandeiraensis, K. atsabensis and S. grunaui have been found with conodonts indicative of the Carnian, but the full local stratigraphic range of these species is uncertain. K. atsabensis occurs at another locality with conodonts suggestive of the Middle Triassic or less likely Carnian. Ophthalmidium sp. cf. O. primitivum has been found at one locality associated with A. bandeiraensis and K. atsabensis in a stratigraphic succession that suggests a correlation to the Carnian or Norian. The ophthalmidiids are found commonly associated with organic-cemented agglutinated and hyaline foraminifera and at some localities common to abundant ostracods and mollusc debris. They were most common in organic-rich carbonate mud of shallow-marine environments.     

Early Miocene cricetids (Rodentia) from the Junggar basin (Xinjiang, China) and their biochronological implications

Among the 14 small mammal species from the early Miocene locality of the northern area of the Junggar basin (northern Xinjiang, China), four species are cricetids (Rodentia): unnamed species of Cricetodon and Eumyarion, and two new species, Karydomys debruijni nov. sp. and Megacricetodon beijiangensis nov. sp. Some aspects of the morphology of Cricetodon sp. are shared by Eucricetodon from the late Oligocene, suggesting that these specimens could be of intermediate form between Eucricetodon and Cricetodon. One tooth of Eumyarion sp. was found, making its determination uncertain, but its morphology is clearly differentiated from the one of Cricetodon sp. The species K. debruijni nov. sp. is established based on its primitive features compared to the species known in Europe and Anatolia, and its specific association of characters compared to Karydomys dzerzhinskii. M. beijiangensis nov. sp. shows many plesiomorphic features compared to the species already described in the middle Miocene of China. Based on both the whole assemblage of rodents and the species of cricetids, the biochronologic position and the age of the locality are discussed. The locality appears to be biochronologically very close to the fauna from the Chul’adyr Formation in Aktau Mountains, but we propose an age slightly older than the one proposed for this fauna, probably equivalent to the MN3 biozone in Europe.