Les sciuridés des gisements karstiques du Miocène inférieur à moyen du sud de la France : nouvelles espèces, phylogénie, paléoenvironnement

We describe sciurids from Lower and Middle Miocene karstic sites located in the south of France. Four new taxa are recognized here: Atlantoxerus martini nov. sp., Atlantoxerus sp. 1, Freudenthalia cuencae nov. sp. and Aragoxerus nov. sp. The last two genera are recognized for the first time in the south of France. A comparison with the Iberian peninsula is carried out, it tackles the problems of diversity, phylogeny and settlement. Hypothesis concerning the predation of these terrestrial squirrels and paleoenvironment is proposed.     

Ozakia,a new genus of winged fruit shared between the Miocene of Japan and western North America

A new genus is recognized based on winged fruits with a single species shared between the Miocene of southwestern Honshu, Japan, and the Miocene of Oregon and Idaho, USA. Calyces of Ozakia emryi gen. et sp. n. were formerly attributed to Heptacodium (Caprifoliaceae) and Amelanchier (Rosaceae); however, newly recovered specimens reveal additional characters that contradict these assignments. The pedicellate fruits are obovate, tapering basally and truncate apically, with about 10 longitudinal ribs, a prominent epigynous synsepalous calyx of five lobes, each with a midvein and a pair of weaker, ascending intramarginal primary veins. The single style has a capitate stigma. Ozakia is considered to represent an extinct eudicot genus, the familial affinities of which remain uncertain. The eastern Asian–western North American disjunction of Ozakia occurrences suggests that this plant traversed the Beringia land bridge during or prior to the Middle Miocene. Relatively few extinct angiosperm genera are known as late as the Miocene.     

New Glyptodont from the Codore Formation (Pliocene), Falcón State, Venezuela, its relationship with theAsterostemma problem, and the paleobiogeography of the Glyptodontinae

One of the basal Glyptodontidae groups is represented by the Propalaehoplophorinae (late Oligocene — middle Miocene), whose genera (Propalaehoplophorus, Eucinepeltus, Metopotoxus, Cochlops, andAsterostemma) were initially recognized in Argentinian Patagonia. Among these,Asterostemma was characterized by its wide latitudinal distribution, ranging from southernmost (Patagonia) to northernmost (Colombia, Venezuela) South America. However, the generic assignation of the Miocene species from Colombia and Venezuela (A.? acostae, A. gigantea, andA. venezolensis) was contested by some authors, who explicitly accepted the possibility that these species could correspond to a new genus, different from those recognized in southern areas. A new comparative study of taxa from Argentinian Patagonia, Colombia and Venezuela (together with the recognition of a new genus and species for the Pliocene of the latter country) indicates that the species in northern South America are not Propalaehoplophorinae, but represent the first stages in the cladogenesis of the Glyptodontinae glyptodontids, the history of which was heretofore restricted to the late Miocene — early Holocene of southernmost South America. Accordingly, we propose the recognition of the new genusBoreostemma for the species from northern South America and the restriction ofAsterostemma to the Miocene of Patagonia. Thus, the available data indicate that the Glyptodontinae would in fact have arisen in the northernmost regions of this continent. Their arrival to more southerly areas coincides with the acme of the “Age of Southern Plains”. The Propalaehoplophorinae are geographically restricted to Patagonia.     

Les ostracodes continentaux au Néogène en Aquitaine (Sud-Ouest France). Répartition spatio-temporelle : le point sur la question

A systematic research of the non-marine ostracodes from the Aquitaine Basin Neogene shows that these animals were locally well represented and able to indicate palaeoecological and palaeoclimatic data, comparable in quality with such data as from Recent continental environments. We provide a list of the taxa, and the stratigraphical distribution during the Lower and the Middle Miocene is indicated, as well as the geographical location in comparison with the estimated shorelines. The recent stratigraphical revisions of some Miocene deposits, mainly marine, from the central, southern and northern parts of the Aquitaine Basin are used. The studied microfauna contains about 20 genera and slightly more than 30 species. Most of the found genera correspond to fresh to brackish ostracodes (particularly Cytheridae and Candonidae). Several genera can indicate environmental characteristics: Candonopsis and Sclerocypris (Upper Aquitanian in age) are intertropical dwellers. Vecticypris from the Lower Miocene could indicate (in analogy with Metacypris) relatively cooler waters existing in these environments.     

Notes on type specimens of European Miocene Talpidae and a tentative classification of old world Tertiary Talpidae (Insectivora: Mammalia)

Survey of the type of the Miocene Talpidae of Europe results in the allocation of several of the types to new or different genera. Three genera and one species previously referred to the family do not belong there. The diversity of Miocene talpids indicates an influx of generic stocks into Western Europe in the early Miocene, probably from Asia. New data provide a basis for a tentative phylogeny and classification of the European genera.     

<Emphasis Type="Italic">Gryposuchus</Emphasis> (Crocodylia,Gavialoidea) from the early Miocene of Venezuela

Here, a fragment of a mandible recently discovered in the Cerro Zamuro site (Castillo Formation, Lara State, northwestern Venezuela) is assigned to the giant gavialoid Gryposuchus. This specimen, recovered from putative brackish environments of the early Miocene (~18 Ma) age, is unequivocally the earliest record of the genus in South America. Gryposuchus, together with the other gryposuchine previously recognized from the Castillo Formation, Siquisiquesuchus venezuelensis, increases the early Miocene taxonomic diversity of the group in the northern Neotropics. This new information from the Castillo Formation supports the conclusion that early gryposuchine evolutionary stages were in coastal, shallow marine or brackish environments, while the presence of some genera, such as Gryposuchus, in middle to late Miocene freshwater environments, is secondary habitat colonization late in the evolution of the clade. Freshwater colonization is probably the result of the gradual adaptation of early marine-adapted gryposuchines to the extensive estuarine-like environments of northern South America lowlands associated with marine transgressions that systematically occurred during the middle Eocene to early Oligocene. This new record is evidence of the wide chronological distribution of Gryposuchus in northern South America, highlighting the importance of this area as the center of origin and radiation of this successful Miocene gavialoid.     

New observations on the Late Miocene–Early Pliocene Lutrinae (Mustelidae: Carnivora,Mammalia) from the Middle Awash,Afar Rift,Ethiopia

New observations on the Late Miocene and Earliest Pliocene mustelids from the Middle Awash of Ethiopia are presented. The Middle Awash study area samples the last six million years of African vertebrate evolutionary history. Its Latest Miocene (Asa Koma Member of the Adu-Asa Formation, 5.54–5.77 Ma) and Earliest Pliocene (Kuseralee and Gawto Members of the Sagantole Formation, 5.2 and 4.85 Ma, respectively) deposits sample a number of large and small carnivore taxa among which mustelids are numerically abundant. Among the known Late Miocene and Early Pliocene mustelid genera, the Middle Awash Late Miocene documents the earliest Mellivora in eastern Africa and its likely first appearance in Africa, a new species of Plesiogulo, and a species of Vishnuonyx. The latter possibly represents the last appearance of this genus in Africa. Torolutra ougandensis is known from both the Late Miocene and Early Pliocene deposits of the Middle Awash. The genus Sivaonyx is represented by at least two species: S. ekecaman and S. aff. S. soriae. Most of the lutrine genera documented in the Middle Awash Late Miocene/Early Pliocene are also documented in contemporaneous sites of eastern Africa. The new observations presented here show that mustelids were more diverse in the Middle Awash Late Miocene and Early Pliocene than previously documented.     

A new duck from the Middle Miocene of Mongolia, with comments on Miocene evolution of ducks

A new relatively large duck, Chenoanas deserta gen. et sp. nov. from the Middle Miocene of the Sharga locality, which is morphologically intermediate between the extant genera Chenonetta and Tachyeres, is described. The diversity of Early and Middle Miocene ducks is discussed. It is noted that some Middle Miocene duck remains are incorrectly referred to the genus Mionetta. The distribution of morphological characters of the humerus in Neogene and extant ducks shows that the present day diversity of ducks apparently results from extinction of some taxa which were formed in the Oligocene-Early Miocene. The distribution of morphological characters in the evolution of diving ducks is evidence that not only the formation of different morphotypes but also so-called ??evolutionary maturation?? of taxa also explains the modern diversity.     

Neogene phasianids (Aves: Phasianidae) of Central Asia: 2. Genera <Emphasis Type="Italic">Perdix,Plioperdix</Emphasis>, and <Emphasis Type="Italic">Bantamyx</Emphasis>

The phasianid genera Perdix, Plioperdix, and Bantamyx from the Neogene of Mongolia and Transbaikalia are reviewed. Based on published data and new material, the diagnoses of Late Pliocene Perdix margaritae Kurochkin and Plioperdix ponticus (Tugarinov) and Late Miocene Bantamyx georgicus Kurochkin are emended. It is shown that a tarsometatarsus from the Upper Miocene of the Pavlodar locality belongs to the genus Palaeoperdix rather than Palaeortyx, as was proposed in the previous studies. Small Neogene Asian phasianids are compared in detail with Neogene taxa from Europe and extant genera.     

Fossil representatives of the family Greenideidae (Hemiptera, Aphidoidea) from the Miocene of Europe

Four new aphid species (Hemiptera, Aphidoidea, Greenideidae) are described on the basis of imprints in oil-shales from the Miocene of Europe (Rubielos de Mora, Spain; Vishnevaya Balka ?Stavropol?, Russia): Eutrichosiphum europaeum nov. sp., Greenidea hispanica nov. sp., Greenideoida (Pentatrichosiphum) turolensis nov. sp. and Mollitrichosiphum rubusensis nov. sp. All the taxa are placed within recent genera of the subfamily Greenideinae. Miocene representatives of this subfamily have been found in the south of Europe. Later changes of climatic conditions limited its geographic range to south-eastern Asia, where it is now represented by over 130 species of seven genera.     

Evolution of bird communities in the Neogene of Central Asia,with a review of the Neogene fossil record of Asian birds

A complete taxonomic review of Neogene birds of continental Asia is provided. To date, avifauna from the latter half of the Miocene and Pliocene of Central Asia (Mongolia and adjacent regions of Inner Asia) are most thoroughly investigated. Available data enable a reconstruction of successive replacement of Early and Middle Miocene avifaunas by communities of the Recent type. Middle Miocene avifaunas of Mongolia include a great number of extinct genera and species, many of which were widespread in Eurasia. Extant genera became dominant in the Late Miocene and taxa close to living species appear in the Late Pliocene fossil record. Late Pliocene communities of birds of Central Asia were complex in genesis, composed of Miocene relicts (Struthio), immigrants from the European regions of the Palearctic (phasianid Plioperdix), North American immigrants (Calcarius), and also autochthonous elements, the origin of which is apparently connected with the arid belt of Central Asia (diverse passerines).     

The geologic history of the Lythraceae

The known fossil record of the Lythraceae has been amplified by recent studies in northern Latin America. A total of 18 genera is recognized in geologic strata ranging in age from lower Eocene to Recent, and among the 22 or 23 modern genera, seven have a documented geologic history. The oldest remains are from an Indo-Malayan Old World warm-temperate to subtropical vegetation preserved in the lower Eocene London Clay flora. The most ancient of extant genera isLagerstroemia and the most recent (among those with an adequate fossil record) isCuphea (middle Miocene to Recent). These represent, respectively, primitive and advanced members of the family, and the paleobotanical record supports current concepts concerning phylogenetic relationships among genera of the Lythraceae. The family apparently had an Old World origin and became differentiated into a distinct modern taxon during Paleocene and early Eocene time.     

First Occurrence of Platycladus from the Upper Miocene of Southwest China and Its Phytogeographic Implications

Platycladus Spach is native to Central China, but its natural occurrences are very difficult to establish. According to molecular phylogenetic data, this genus might have originated since the Oligocene, but no fossil record has been reported. Here, we describe eight foliage branches from the upper Miocene in western Yunnan, Southwest China as a new species, P. yunnanensis sp. nov., which is characterized by foliage branches spread in flattened sprays, and leaves decussate, imbricate, scale-like and dimorphic. The leaves are amphistomatic, and the stomata are elliptical or oblong, haplocheilic, and monocyclic type. Based on a detailed comparison with the extant genera of Cupressaceae sensu lato, our fossils are classified into the genus Platycladus. The occurrence of P. yunnanensis sp. nov. indicates that this genus had a more southernly natural distribution in the late Miocene than at present. Molecular phylogeny and fossil records support a pre-Oligocene common ancestor for the genera Platycladus, Microbiota and Calocedrus. The separation of the three taxa was most likely caused by the arid belt across Central China during the Oligocene. In addition, the cooling down of the global temperature and the strengthening of Asian monsoon since the Miocene will further promote the migration of these genera.     

Global phylogeny and new classification of the Rapaninae (Gastropoda: Muricidae), dominant molluscan predators on tropical rocky seashores

The monophyly of the muricid subfamily Rapaninae has recently been confirmed with molecular techniques, but its composition and the relationships among its constituent genera remain unclear. We use four genes (28S rRNA, 12S rRNA, 16S rRNA and cytochrome c oxidase subunit I, COI) to construct a Bayesian phylogeny of 80 rapanine species (73% of the approximately 109 currently accepted), representing 27 of the 31 nominal genera. This is the most complete phylogeny of this taxonomically confusing subfamily yet produced. We propose a revised phylogenetic classification of the Rapaninae, assigning the recognized species to 28 genera. Most of the morphologically-defined rapanine genera are considered valid, including Purpura, Drupa, Thais and Nassa, but many of them are here restricted or redefined so that they are monophyletic. In particular the familiar genus Thais is narrowly restricted to a single species. Many groups previously accepted as subgenera, including Mancinella, Vasula, Thalessa and Thaisella, are here accorded full generic rank. We describe one new genus, Indothais. While we do not formally alter species-level taxonomy, we show molecular evidence for two cryptic species and several instances of probable species synonymy. We estimate the age of diversification of the Rapaninae as Late Cretaceous (75.9 Ma) and of many of its genera as Miocene.     

Re-assessment of the Oligocene genera Prosotherium and Propachyrucos (Hegetotheriidae,Notoungulata)

Several systematic revisions of the Hegetotheriidae have been published in the last twenty years, but some important taxonomic work remains limited to unpublished studies. In one such thesis, the late Oligocene genera Prosotherium and Propachyrucos were revised, so that Prosotherium garzoni and Propachyrucos smithwoodwardi were considered the only valid species for each genus. Later authors loosely accepted these informal revisions, but recent phylogenetic coding has yet to accurately reflect these revisions, with character states often at odds with the known material for these genera. This study re-examines most of the fossil material assigned to Propachyrucos and Prosotherium, including both published and unpublished fossils, and contributes to a better understanding of the systematics, taxonomic diversity and early morphological evolution of the pachyrukhines. We conclude that Prosotherium garzoni and Propachyrucos smithwoodwardi are indeed the only valid species for each genus, confirming the influential but unpublished revisions that have become widely accepted. The known material for these species is clarified to aid future phylogenetic studies. At the same time, Propachyrucos aequilatus and Pr. robustus are herein considered nomina dubia. Additionally, Miocene species originally ascribed to Propachyrucos, along with unpublished material loosely assigned to the same genus, are here synonymized with other genera. Finally, several fossils previously recognized as Prosotherium sp. are here recognized as P. garzoni.     

The scleractinian genusHydnophora (revision of Tertiary species)

This report presents a systematic revision of the Tertiary species of the common reef-building coralHydnophora. Major diagnostic characters of the various Tertiary genera that have been commonly confused withHydnophora (Leptoria,Monticulastraea, Staminocoenia, Michelottiphyllia andAngeliphyllia) are defined and subsequently compared in order to establish differences and synonymies. With the exception ofLeptoria, all other genera are considered synonyms ofHydnophora. The forty-five Tertiary species ascribed toHydnophora, or to synonymous genera, have been revised and type material analyzed. Collected material from Oligocene Italian localities and Miocene localities from Somalia and Pakistan has been also analyzed in order to provide a consistent taxonomy for distinguishing species within the genus, especially for the Mediterranean Tertiary. According to this report, of the forty-five species ofHydnophora previously described, only twenty-one appear to be distinct. The Tertiary distribution of the genus, which started in the Late Paleocene, clearly shows that species richness increased significantly from Paleocene to Miocene. Originations of species were mostly concentrated during two time intervals, respectively the Chattian for the Mediterranean and the Burdigalian for Eastern Tethys. As regards the Mediterranean, the genus developed only during Chattian time with five fully described species. The genus became extinct in both Caribbean and western-central Mediterranean regions at the end of the Oligocene and subsequently developed in eastern Tethys regions during the Miocene. A new name is proposed for the only Paleocene species:Hydnophora gregoryi.     

First fossil record of the catfish genus Sorubim (Siluriformes,Pimelodidae), from the Late Miocene of Paraná, Northeastern Argentina

The aim of the present contribution is to describe a partial fossil skull belonging to the catfish genus Sorubim. The specimen originates from the Late Miocene Ituzaingó Formation, at Paraná locality, Entre Ríos Province, Argentina. The material described here (MACN Pv-14224) was determined just to genus because the living species of Sorubim are morphologically similar. Presence of Sorubim is in concordance with the hypothesis indicating that most extant pimelodid genera were already present by the Late Miocene. Present finding constitutes the first fossil record for the genus.     

Upper Eocene to Middle Miocene ostracode faunas and paleo-oceanography of the North Coastal Belt,Jamaica, West Indies

The ostracode fauna of the Montpelier Group (Upper Eocene-Middle Miocene) exposed in the western part of the North Coastal Belt of Jamaica contains representatives of three paleo-environments. Allochthonous shelf and littoral species, characterized by abraded carapaces and eye tubercles, and a diverse group of archibenthal (slope) forms are present throughout. Species restricted to the World Ocean Psychrosphere (> 1000 m), notably Bradleya dictyon, Australoecia tipica, Agrenocythere hazelae and Macrocypris spp., first occur in sediments of earliest Miocene age (planktonic foraminiferal zone N4). Their presence establishes a minimum age for the entry into the Cayman Trench of frigid (<8–10°C) water masses drawn from the Atlantic thermohaline stratification.Upper Eocene and Oligocene assemblages are dominated by smooth, blind genera such as Krithe, Messinella and Bythocypris and lived in lower thermospheric conditions (10°C) at or near the base of the thermocline (700– 900 m). During the Early Miocene, downfaulting of the north island slope of Jamaica in response to southward tilting of the Nicaraguan Rise brought the Montpelier depositional site into contact with progressively deeper and colder water-masses. This subsidence culminated in the late Early Miocene; faunas of this age contain large numbers of Bradleya dictyon, Agrenocythere hazelae, Macrocypris sp. 1, Bairdia oarion and Bairdoppilata cassida. They suggest paleodepths of 1500–2000 m and the local presence of a 3–4° water-mass tentatively identified as the North Atlantic deep water. If this interpretation is correct, then the maximum sill-depth and water-mass configuration of the Miocene Cayman Trench have persisted to the present. Middle Miocene assemblages indicate a return to paleodepths of 1000–1500 m heralding the pronounced Upper Miocene to mid-Pleistocene tectonism which elevated Montpelier strata above sea level. An alternative view attributes the Miocene ostracode succession in the Montpelier to episodes in the development of the Atlantic circulation as recognized in the northeast Atlantic.Montpelier deposition took place either on a broad step intervening between the northern edge of the Clarendon Platform and the abyssal basins of the Cayman Trench or on a Tertiary analog of the existing north island slope. These results have emphasized the value of detailed taxonomic and morphologic studies of deep-sea ostracodes in geohistorical reconstruction.     

A functional multivariate analysis of Mesopithecus (Primates: Colobinae) humeri from the Turolian of Greece

The genus Mesopithecus is well represented in the late Miocene of Greece by several recognized species. The present paper investigates functional aspects of the humeri of Mesopithecus delsoni/pentelicus, M. pentelicus and M. aff. pentelicus of several Turolian sites from central and northern Greece, using multivariate approaches. For these purposes, we selected significant humeral functional features, which were represented by 23 linear dimensions and three angles on 14 fossil humeri and 104 humeri from 10 genera and 22 species of extant African and Asian Colobines. All size-adjusted measurements were examined through a principal components analysis, followed by a discriminant function analysis, and a canonical variates analysis. All analyses revealed that the selected characters were able to discriminate between extant colobine genera. Functional groups, such as arboreal walking/climbing, arboreal walking/suspensory and semi-terrestrial walking, were set apart from a central cluster formed by the arboreal walking and arboreal walking/terrestrial groups. This cluster also grouped the three studied Mesopithecus species, which were mainly classified as arboreal walkers with significant terrestrial activities. These observations match with paleoenvironmental reconstructions and the suggested opportunistic feeding habits. Moreover, the overall arboreal/terrestrial locomotor tendencies of these fossil forms are discussed in relation to their earlier migration from Africa and later dispersal to eastern and southern Asia.