Rodents and insectivores from the late Miocene of Romerales (Fortuna Basin,Southern Spain)

Abstract

The Neogene Fortuna Basin (Murcia Region, SE Spain) is rich in microvertebrate sites. Its continental sections include localities extended from the middle Turolian (MN12) to the early Ruscinian (MN14). However, there are few works dealing with the taxonomy of these fossil assemblages. In this paper we provide a complete taxonomic study of the rodents and insectivores from three levels (ROM-2B, ROM-2C and ROM-3A) within the Romerales section. We infer a late Turolian age (late Messinian) for these levels, among which the richest and most diverse level is ROM-C, including at least 11 different taxa. In addition, the paleoecological analysis of these fossil assemblages suggests the dominance of open herbaceous meadows under temperate climate during the formation of these sites, with a slight decrease in temperature and humidity from ROM-2B to ROM-2C.     

The late Neogene rodent succession of the Guadix–Baza Basin (south‐eastern Spain) and its magnetostratigraphic correlation

In this paper a magnetostratigraphically calibrated biozonation of the Miocene–Pliocene continental record of the Guadix–Baza Basin (south‐eastern Spain) is presented. This biozonation is based on a rodent succession which ranges from the latest Miocene (c. 6 Ma) to the latest Pliocene (c. 2.6 Ma). A total of nine biozones have been defined for the late Miocene and Pliocene, all of them based on the range or concurrent‐range of rodent species: Apodemus gudrunae – Apocricetus alberti Zone, Apocricetus barrierei Zone, Paraethomys aff. abaigari Zone, Trilophomys Zone, Mimomys davakosi Zone, Dolomys adroveri Zone, Mimomys hassiacus Zone, Mimomys polonicus Zone and Kislangia ischus Zone. A magnetobiostratigraphical correlation has been established between these biozones and the standard ATNTS scale, on the basis of the palaeomagnetic analysis carried out on the sections of Negratín, Botardo‐1 and Gorafe. The correlation has been completed with previous palaeomagnetic analysis in the sections of Galera and Zújar. The magnetobiostratigraphical correlation here established indicates a late Messinian age for the Apodemus gudrunae – Apocricetus alberti Zone, a Zanclean age for the Apocricetus barrierei, Paraethomys aff. abaigari, Trilophomys and Mimomys davakosi zones and a Piazencian age for the Mimomys hassiacus, Mimomys polonicus and Kislangia ischus zones. The Dolomys adroveri Zone is mostly Zanclean in age, but its uppermost part belongs to the Piazencian. Therefore, unit MN13 is correlated with the late Messinian, MN14 is correlated with the early Zanclean, most of MN15 is correlated with the late Zanclean, while the uppermost part of MN15 and MN16 are correlated with the Piazencian.     

Biostratigraphy and sedimentary evolution of Late Miocene and Pliocene continental deposits of the Granada Basin (southern Spain)

The Late Miocene and Pliocene continental sediments in the Granada Basin (southern Spain) have yielded large amounts of fossil small mammals in 37 localities from 11 sections. The aim of this paper is to integrate faunistic, stratigraphic, and sedimentary criteria to unravel the geological history of the continental infilling of the basin. The palaeontological study has led to a detailed biozonation on the basis of rodents, which helps to correlate in detail the different sedimentary units found in the basin, and to follow the changes of the different sedimentary systems and their palaeogeographical evolution through time. Combination of the proposed biostratigraphy and the reinterpretation of the magnetostratigraphic analyses of the Barranco del Purcal section allows us to assign an absolute age slightly older than 5.23 Ma to the Turolian–Ruscinian boundary (MN13‐MN14).     

Les Cases de la Valenciana,a new early Miocene small-mammal locality from the Vallès-Penedès Basin (Catalonia,Spain)

Abstract

The Valles-Penedes Basin (Catalonia, Spain) is classical area for the study of Miocene land mammal faunas. Nevertheless, the early Miocene part of the record has deserved little attention as compared to younger intervals. Most notably, the small mammals of this age have not been described in detail, consequently hampering the correlation of the Valles-Penedes record with other chronological schemes. In this work we describe the rich and diverse small mammal fauna from Les Cases de la Valenciana site (Gelida, Alt Penedès) which includes marsupials, eulipotyphlans, lagomorphs and rodents. On the basis of the presence of the cricetids Megacricetodon and Democricetodon this site is correlated with European Neogene zone MN4, yielding an age of 17–16 Ma. However, the rodent assemblage is comparable to that of chronologically close localities of the Calatayud-Montalbán Basin (Aragon, Spain), indicating that the same biochronological scheme can be applied to both areas. In this way, the coexistence of the eomyids Ligerimys ellipticus and Ligerimys florancei coupled with the presence of Megacricetodon primitivus indicates a correlation with local biozone Ca of the Calatayud-Montalban Basin, ranging from 16.3 to 16 Ma. Finally, the correlation of other early Miocene sites of the Valles-Penedes Basin is discussed and refined.     

Body size structure in north-western Mediterranean Plio-Pleistocene mammalian faunas

Aim We investigated the patterns of body‐size changes of the north‐western Mediterranean Plio‐Pleistocene large mammal faunas (excluding rodents, bats, lagomorphs and insectivores) in order to identify the tempo and mode of the major shifts in body size distribution, and to put them in the context of Plio‐Pleistocene environmental changes and the development of the Mediterranean climate. Location We analysed fossil faunas of Spain, France and Italy. A set of recent regional faunas from several macroclimatic regions was selected to serve as elements for comparison of the size distribution of past faunas, consisting of: Spain, France and Italy together, Florida, California, Central Chile, Indochina, India, Korea‐Manchuria, Malawi, The Cape, North Africa, Turkey and Australia. Methods Mammal species were grouped into five body size categories for carnivores and four categories for noncarnivore species. The number of species in each size category was computed and the resulting matrix of body weight classes × regions and time intervals was used as an input matrix in a Correspondence Analysis. Results Recent and fossil faunas strongly differ in body size structure. The distribution of recent faunas within the CA seems to reflect both ecological and historic factors, intertwined in a complex fashion. No clear relationship has been observed between body size structure and environmental factors. During the late Pliocene to early Pleistocene there were only minor changes in the pattern of size distribution, although plant communities were in a transition process from subtropical forests to Mediterranean woodlands and steppes. The major change in body size structure of the north‐western Mediterranean fauna occurred at the Galerian, around 1 Ma ago. This marked the beginning of the modern fauna, and a general trend towards a larger body size, reduction in the number of medium sized herbivores, and an increase of large herbivores and megaherbivores. Main conclusions The Plio‐Pleistocene faunas lack modern analogues. The body size structure of mammalian regional faunas appears to be strongly dependent on historical factors. The only major shift in body size distribution occurred during the Plio‐Pleistocene, in the late Villafranchian‐Galerian transition, coincident with the onset of the Pleistocene high intensity glacial cycles.     

Percrocuta miocenica (Percrocutidae,Carnivora) from the middle Miocene of Brajkovac (Central Serbia)

This paper describes a well-preserved hemimandible of Percrocuta miocenica from Brajkovac (Lazarevac municipality, Central Serbia). Based on the faunal remains recovered so far, the site is attributed to Mammal Zone MN6 (Langhian, middle Miocene). Apart from Prebreza, this is only the second site where remains of P. miocenica have been found in Serbia, and the third one in the Balkans. The newly discovered fossil, along with other taxa (e.g., Bunolistriodon meidamon, Giraffokeryx punjabiensis, Alloptox sp.), underlines the similarities between the middle Miocene Balkan and Anatolian mammal faunas.     

Biostratigraphy or biochronology? Lessons from the Early and Middle Miocene small Mammal Events in Europe

Since the proposition in 1975 of the European Neogene Mammal (MN) scale by Pierre Mein, the amount of taxonomical, stratigraphical and chronological information around Europe has increased exponentially. In this paper, the stratigraphical schemes of three of the best studied areas for the Lower and Middle Miocene, the Aragonian type area in Spain and the Upper Freshwater Molasse from the North Alpine Foreland Basin in Switzerland and Bavaria, are compared. The correlation of their local biostratigraphies are discussed. Sixteen rodent's events are studied and ranked in the three areas according to their local biostratigraphy. This study shows, and quantifies for the first time, the significant asynchronies of the different included rodent events. The MN-system is discussed in the light of those results. In accordance, we propose that it is still useful but only in a biochronological way, as a sequence of time-ordered reference localities allowing coarse long-distance correlations. In order to obtain better temporal resolution, this system has to be combined with local biostratigraphies that are well calibrated to the time scale, implementing the information about synchrony and diachrony of mammal events in different areas.     

Rodents and Insectivores from the Upper Miocene of Molayan, Afghanistan

Although Molayan is the richest fossil mammal locality in Afghanistan, only a few species have been studied. This paper describes three rodents (Hystrix aryanensis sp. nov., Parapeolomys sp. and Pseudomeriones latidens sp. nov.) and one insectivore (Erinaceus sp.). Lithostratigraphical correlations and biostratigraphical studies in the Khurdkabul Basin provide evidence that the Molayan locality is younger than three other localities in this basin: Sherullah, Taghar and Ghazgay. In addition, the taxa described here, along with several species of large mammals from Molayan, permit correlations with the Siwalik succession in Pakistan to the east, and with European Neogene mammal ages to the west. The age of the Molayan fauna is concluded to be mid Turolian. Observations on the mammal faunas from the Khurdkabul Basin suggest that the altitude of the area, at present over 2000 m, was much lower during the late Miocene. Uplift of the basin probably occurred no earlier than the ?late Pliocene.     

New insights on Cricetodontini (Rodentia,Mammalia) from the Duero Basin,Spain

Abstract

The tribe Cricetodontini is a common cricetid group found in several European basins from the Miocene. Here we present a study of the fossils of this group found in the Duero Basin. We updated the biostratigraphical assignation of some of the localities in which several species of Cricetodontini have been found. Cricetodontini remains from eight localities from the central sector of the Duero Basin have been described, measured and assigned to a species. The presence in these localities of Hispanomys aguirrei, H. lavocati, H. nombrevillae and H. aragonensis has allowed correlating them to the biostratigraphic scale built for the Miocene in Calatayud-Daroca Basin, identifying biozones G3, H and I (MN7/8 – MN10, Late Aragonian – Early Vallesian, Middle – Late Miocene). Furthermore, this study constitutes the first citation of this species in this basin, except H. aguirrei, previously described in the Duero Basin. After this work, the biostratigraphical assignation of the studied sites is now well known. We evidenced the resemblance of Duero and Calatayud-Daroca basins.     

First macroflora data from La Val (Late Oligocene/Early Miocene), Estadilla (Huesca,Spain)

This paper reports a previously unknown leaf-flora from the Upper Oligocene/Lower Miocene of the Ebro Basin, NE Spain, a period with a relatively poor vascular-plant fossil record in Southern Europe. The presence of Acrostichum sp. is also important. This fern is extremely significant from the point of view of palaeoecology and the depositional environment. The macroflora appears to yield sufficient morphological characteristics to be identified at genus level, and sometimes at species level, although cuticles are not preserved. This article presents the first data obtained from the new outcrop at La Val; the following families have been identified: Pteridaceae, Dennstaedtiaceae, Equisetaceae, Pinaceae, Lauraceae, Hamamelidaceae, Betulaceae, Myricaceae and Salicaceae. The fossil plant assemblage is correlated with the Cadibona floristic complex (Mai, Tertiäre Vegetationsgeschichte Europas. Methoden und Ergebnisse, Gustav Fischer, Jena, 691 pp., 1995) and suggests a subtropical-to-warm temperate climate, rainy and wet, with a short dry season. The age of the assemblage is Late Oligocene/Early Miocene.     

A new coral‐associated decapod assemblage from the Upper Miocene (Messinian) Upper Coralline Limestone of Malta (Central Mediterranean)

Abstract: A rich coral‐associated decapod assemblage is recorded from the ‘Depiru Beds’ of the upper part of the Upper Coralline Limestone (Messinian, Upper Miocene), from the island of Malta. Nineteen species within 17 genera have been discovered, where 14 genera are new for Malta. Four new species are described, namely Micippa annamariae sp. nov., Pilumnus scaber sp. nov., Panopeus muelleri sp. nov. and Herbstia melitense sp. nov. Herbstia melitense sp. nov. constitutes the first record of the genus from the fossil record in the Mediterranean region. This discovery more than doubles the number of known fossil decapod species from Malta. The fossil bivalve Jouannetia (J.) semicaudata Des Moulins, 1830 and the extant decapod Maja goltziana D’Oliveira, 1888, are also recorded for the first time from Malta. Other Neogene coral‐associated decapod assemblages are investigated and correlated with the new assemblage from Malta. The migration of taxa between the Mediterranean region and the Paratethys, particularly during the Lower Badenian (Langhian), is evidenced by the strong affinity of the Maltese decapod assemblage with that of the Middle Miocene Badenian assemblages from Hungary, Poland and Ukraine. Upper Miocene, Messinian assemblages from Spain, Algeria and Morocco are also similar to that from Malta.     

The Late Neogene mammal biochronology in the Loess Plateau,China

For lacking of absolute dating, and because of the strong mammalian faunal endemism, the Chinese late Neogene has long been subdivided into mammalian ages mostly based on isolated local faunas by evolutionary stages of fossil taxa. The correlation with European stages and or mammalian units remains unsatisfied. We report the recent advances of the land mammal biochronology of late Neogene based on fossils found from continuous sections located at Lantian, Shaanxi Province and Lingtai, Gansu Province. There recognized three biozones for the late Miocene by fossils from the Bahe and Lantian formations, and three biozones for Pliocene on the data from Lingtai. The detailed biochronology work in combination with paleomagnetic data may improve the precision of correlation in the continental scale.     

The Ramblian-Aragonian boundary and its significance for the European Neogene continental chronology. Contributions from the Ebro Basin record (NE Spain)

In this paper we report on the results of a paleontological and paleomagnetic sampling carried out in the Miocene of the central Ebro Basin. It includes the sections of Albalatillo, Lanaja, La Almolda and San Caprasio in the Sierra de Alcubierre, which delivered six new micromammal levels ranging from the MN3 to MN5 mammal units. The magnetobiostratigraphic study of the Sierra de Alcubierre enables one to shed light on the chronology of the Early to Middle Miocene European mammal biozonation (e.g., the Ramblian-Aragonian boundary). As a result, the first occurrence of the “Miocene Cricetids” and, therefore, the lower boundary of MN4 – zone B, is set back to the lower part of chron C5Cr, thus reducing significantly the supposed discrepancy of the First Occurrence of Democricetodon in the Swiss Molasse and the Aragonian type-section. Another significant result is the persistence of Vasseuromys in the Ebro Basin up to the Middle Miocene (MN5).     

Première biozonation du Pléistocène Européen,principal résultat biostratigraphique de l'étude des Rhinocerotidae (Mammalia,Perissodactyla) du Miocène terminal au Pléistocène supérieur d'Europe Occidentale

For the Uppermost Miocene the already known zones MN 9 to MN 13 are used without any change; they prove to be particularly useful for the study of fossil rhinocerotids. The Plio-Villafranchian age corresponds to the zones 14 to 19, the definition of the first five being completed and the last being new. Middle to Upper Pleistocene age deals with the zones 20 to 26, all being new and defined following the same principles.     

Paleoecology of the Miocene fossil mammal fauna from Bełchatów (Poland)

Miocene fauna of land mammals is known from numerous fossil localities in western Europe but its remains are rare in the north-eastern part of this continent. The open brown coal mine at Bełchatów in central Poland revealed numerous remains of small and large mammals representing three Miocene biozones from MN4 to MN8/9. They indicate the presence of relatively stable subtropical conditions during all the time of the Miocene deposition in the Bełchatów basin with only slight cooling before the end of the sedimentation.

     

New palaeontological assemblage, sedimentological and chronological data from the Pleistocene Ma U'Oi cave (northern Vietnam)

This paper describes recent material gathered during the second fieldwork at Ma U'Oi in November 2002 by a Vietnamese–French–Japanese team. The Ma U'Oi cave, located in the province of Hoà Binh (60 km SW from Hanoi), northern Vietnam, belongs to a karstic network developed in Triassic dark-grey limestones.

The cave is filled with coarse-grained breccias containing numerous fossil remains, partially preserved at several loci inside the cave (wall, vault and ground). We describe new teeth which confirm the occurrence of mammal taxa already mentioned at Ma U'Oi (Bacon et al., 2004)[Bacon, A-M., Demeter, F., Schuster, M., Long, V.T., Thuy, N.K., Antoine, P-O., Sen, S., Nga, H.H., Huong, N.T.M., 2004. The Pleistocene Ma U'Oi cave, northern Vietnam: palaeontology, sedimentology and palaeoenvironments. Geobios 37, 305–314], while others, mainly microvertebrates, emphasize the occurrence of new species for the Pleistocene of Vietnam. We report here, for the first time, the occurrence of these microvertebrates of different groups (primates, rodents, insectivores, small reptiles and amphibians) in the faunal assemblage. Among mammal taxa, the presence of one more hominid affiliated to archaic Homo is also attested by our findings. U/Th dating carried out on 2 samples extracted from breccia speleothems confirms the biochronological estimate, with fossiliferous fillings ranging from late Middle Pleistocene to Late Pleistocene.     

Small mammal (rodents and lagomorphs) European biogeography from the Late Oligocene to the mid Pliocene

Aim To analyse the fossil species assemblages of rodents and lagomorphs from the European Neogene in order to assess what factors control small mammal biogeography at a deep‐time evolutionary time‐scale. Location Western Europe: 626 fossil‐bearing localities located within 31 regions and distributed among 18 successive biochronological units ranging from c. 27 Ma (million years ago; Late Oligocene) to c. 3 Ma (mid Pliocene). Methods Taxonomically homogenized pooled regional assemblages are compared using the Raup and Crick index of faunal similarity; then, the inferred similarity matrices are visualized as neighbour‐joining trees and by projecting the statistically significant interregional similarities and dissimilarities onto palaeogeographical maps. The inferred biogeographical patterns are analysed and discussed in the light of known palaeogeographical and palaeoclimatic events. Results Successive time intervals with distinct biogeographical contexts are identified. Prior to c. 18 Ma (Late Oligocene and Early Miocene), a relative faunal homogeneity (high interregional connectivity) is observed all over Europe, a time when major geographical barriers and a weak climatic gradient are known. Then, from the beginning of the Middle Miocene onwards, the biogeography is marked by a significant decrease in interregional faunal affinities which matches a drastic global climatic degradation and leads, in the Late Miocene (c. 11 Ma), to a marked latitudinal pattern of small mammal distribution. In spite of a short rehomogenization around the Miocene/Pliocene boundary (6–4 Ma), the biogeography of small mammals in the mid Pliocene (c. 3 Ma) finally closely reflects the extant situation. Main conclusions The resulting biogeographical evolutionary scheme indicates that the extant endemic situation has deep historical roots corresponding to global tectonic and climatic events acting as primary drivers of long‐term changes. The correlation of biogeographical events with climatic changes emphasizes the prevalent role of the climate over geography in generating heterogeneous biogeographical patterns at the continental scale.     

Late Cretaceous Mammal Tracks from North America

Mammal tracks from the latest Cretaceous (Campanian-Maastrichtian) of Colorado are described as Schadipes crypticus ichnogen. et ichnosp. nov., on the basis of material from the Laramie Formation in Golden, eastern Colorado. This ichnospecies, and a closely related form (Schadipes sp.) from the Mesaverde Group of western Colorado, represent the only mammal tracks so far identified from the Upper Cretaceous. A possible mammal track from North Africa (Agadirichnus elegans) was originally attributed to a lizard/lacertilian. Other purported Lower Cretaceous mammal tracks are based on isolated specimens of materials that are dubious or as yet undescribed in detail. Morphologically, Late Cretaceous mammal tracks resemble those of some modern rodents. However, based on the dominant mammalian elements of faunas at that time they are probably of marsupial or multituberculate affinity.     

Desmaninae (Talpidae, Mammalia) from the Pliocene of Tollo de Chiclana (Guadix Basin, Southern Spain): Considerations on the phylogeny of the genus Archaeodesmana

The fossil Desmaninae (water-moles) from the Pliocene continental deposits of Tollo de Chiclana (Guadix Basin, Southern Spain) are described. A new species, Archaeodesmana elvirae, is defined from the locality of Tollo de Chiclana-1 (upper Ruscinian). This species is characterized by relatively small canines and premolars (except the P4) and large P4 and molars, besides several morphological features. The presence of Archaeodesmana brailloni is reported from the locality of Tollo de Chiclana-1B (uppermost Ruscinian). A small sample assigned to the genus Archaeodesmana is described from the lower Villafranchian site of Tollo de Chiclana-3, which cannot be determined at the specific level. The phylogenetic relationships between the different species of Archaeodesmana are reconsidered in the light of the recent findings, which support the idea of a more complex phylogeny than previously proposed for this genus. The populations from the Guadix Basin, previously assigned to Dibolia dekkersi (= Archaeodesmana getica), are here considered to belong to a different (unnamed) species, which is the ancestor of A. elvirae. On the other hand, the new species A. elvirae is proposed as the ancestor of A. brailloni.