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1.
An association of limnic ostracodes has been discovered in the upper part of the Irbzer Formation, of Maastrichtian age, in the Moroccan Middle-Atlas. A new species is described, Gomphocythere achloujensis nov. sp. Paracandona occitanica, which is very common in terminal Cretaceous non-marine deposits of southern Europe (France, Spain), is found for the first time on the south Tethyan margin.  相似文献   

2.
A microfauna composed of 11 species of ostracodes belonging to 11 genera have been recovered from the Bhanness Formation of Kimmeridgian age, in Central Lebanon. Four species are new and are described herein: Ektyphocythere dahressawanensis nov. sp., Dicrorygma (Orthorygma) libanensis nov. sp., Citrella? elongata nov. sp. and Procytherura inflata nov. sp. From a palaeobiogeographical standpoint, this fauna characterizes the North Gondwana province which differs from the South Gondwana province, particularly by the presence of the genus Schuleridea and the absence of the genus Majungaella.  相似文献   

3.
Three Megacricetodon species are recognized in the Middle Miocene locality of Blanquatère 1 (Languedoc-Roussillon province, France). Two are new, the small-sized M. tautavelensis nov. sp. the medium to large-sized M. aunayi nov. sp., the third one being the already known M. “collongensis-gersii”, a medium-sized species found in other Miocene localities of the area. Size and morphology differentiate these species. Such a high number of contemporaneous species of the genus Megacricetodon is found for the first time in a Miocene locality in the region and indicate that the evolution of this genus in western Europe is likely more complicated. It may testify both of a biogeographical differentiation and of migration events. According to our calibration charts, the deposit is dated ca. 16 Ma ago. The position of Vieux-Collonges (MN 5) and Sansan (MN 6) on the biochronological scale is also discussed, as well as the estimated age of the biozonal boundaries MN 3/MN 4, MN 4/MN 5 and MN 5/MN 6.  相似文献   

4.
The amber of Le Mas d’Azil (Ariège, France), fashioned by the Magdalenian people of Le Mas d’Azil cave, was collected in clay levels rich in Cupressinoxylon Göppert, of the Campanian Labarre Sandstone Formation, which is a large deltaic set, infilling the sub-Pyreneean trough. The amber pieces are small and resemble modern resin exudates on coniferous trunks. We describe following micro-inclusions. Actinomycetes: Cardonia stellata, nov. gen., nov. sp., located close to the surface of amber pieces, is abundant and displays chains of conidia and isolated aleuriospore. Nocardiopsis ? sp. D is rare. Actinomycete “de type Salignac” is abundant. Its filaments often display a tendril shape, which seems to prelude to a mycelium fragmentation. Other bacteria: Leptotrichites resinatus Schmidt ( Schmidt and Schäfer, 2005), poorly represented, is more variable than the already known material; cf. Sphaerotilus sp., very abundant, also displays differences with the Cenomanian “Sphaerotilus sp.”. Eukaryotes: one fungal filament, and a group of spores, pollens or cysts. Inorganic inclusions: gas bubbles, pseudo-protists of B and C? types, and tiny, transparent, cubic crystals. It seems that most of the quoted prokaryotes were resinicolous organisms, able to settle on the surface of the exudate, and grow in the resin, after inoculation either by a contact with the substrate, or by an anemophilic dispersion of spores. This “taphonomic way” seems here to be more general than trapping.  相似文献   

5.
The Candona clivosa-group, a new group of Candoninae - is erected on the base of the folded inner lamella observed on the postero-ventral border of the female valve. The elongated sub-triangular and rectangular valves of this group are described from the Miocene and Quaternary deposits of Europe. A folded inner lamella is also observed in 11 species of Candona from the Upper Miocene of the Turiec Basin of which 8 are new - Candona fatrica nov. sp., C. tatrica nov. sp., C. lacustris nov. sp., C. palustris nov. sp., C. stagnosa nov. sp., C. laterisimilis nov. sp., C. jiriceki nov. sp. and C. incurva nov. sp. They show a higher variability of the outline, calcification of the valves and width of the zone of concrescence. The extrinsic and intrinsic aspects of this morphological diversification in the Turiec Basin are discussed.  相似文献   

6.
The discovery in the uppermost Jurassic of Lebanon of a species of the ostracod genus Microceratina Swanson, 1980 (Eucytherurinae), of which the oldest known species was until now of Maastrichtian age, confirms the Tethyan origin of this genus. Two new species are created: Microceratina bhannesensis nov. sp. from the Upper Jurassic (Kimmeridgian) of Lebanon, and Microceratina azazoulensis nov. sp. from the Cenomanian of Morocco. The genera Chapmanicytherura Weaver, 1982 and Erratacytheridea Herrig et al., 1997, are considered as probable junior synonyms of Microceratina. An exhaustive bibliographical analysis allowed to identifying several other Cretaceous species susceptible to be assigned to the genus Microceratina.  相似文献   

7.
Found in Chiapas (South-East of Mexico), Praealveolina michaudi nov. sp. and Chubbina jamaicensis (of Campanian-Maestrichtian age) are described, both evolved from Nummoloculina sp. while Raadshoovenia guatemalensis (upper Paleocene-lower Eocene) arises from Quinqueloculina. We precisely analyze and modelize the nepionic coiling during the evolutionary change from Miliolacea to Alveolinacea. During ontogenesis as well as during phylogenesis, quinqueloculine coiling progresses to streptospiral and then to planispiral chamber arrangement with the increase of volume of embryo and of chambers. Appearance of these large foraminifers are understood as a consequence of the rise of K-strategies in their mode of life, following the development of photosynthetic symbioses.  相似文献   

8.
L Rulleau  P Neige 《Geobios》2003,36(3):317-348
The genera usually considered into the Bouleiceratinae subfamily belong in fact to different lineages of the Hildoceratidae family. An approach using paleogeographical, stratigraphical and morphological arguments on one hand and a cladistic approach on the other hand have allowed to separate 3 clusters with different paleogeographical and stratigraphical localisations. These are:
the Bouleiceratinae s.s. (genera Bouleiceras, Nejdia and Kohaticeras) from lower Toarcian;
the Leukadiellinae (genera Leukadiella and Renziceras) from middle Toarcian;
and the Paroniceratinae (genera Frechiella, Paroniceras and Oxyparoniceras) from middle and upper Toarcian. These latters are mainly present and the Tethyan domain, but are also known in the NW of Europe and especially in France where new populations have been studied in the Causses, in the centre-ouest and in the Lyon area. New taxa have been erected here: Oxyparoniceras (Neoparoniceras) nov. sub. gen., O. (N.) brocardi nov. sp. and O. (N.) sciaui nov. sp.
  相似文献   

9.
Forty-four ostracod species are recognised from the upper part of the Eifelian to the base of the Famennian of the Djebel Mech Irdane, Bou Tchrafine and El Atrous sections, in the Tafilalt. The majority are in open nomenclature, and one is new: Tubulibairdia tafilaltensis nov. sp. Ostracods belong principally to the Eifelian Mega-Assemblage and they are generally indicative of poorly oxygenated relatively deep marine environments below storm wave base. However, in the base of the Famennian of the Bou Tchrafine section, ostracods belong to the Myodocopid Mega-Assemblage indicative of strong hypoxic water conditions. They confirm that the hypoxic water conditions linked to the “Upper Kellwasser Horizon”, subsisted in North Africa, in the extreme base of the Famennian. Twenty-four ostracod species are recognized in the Djebel Mech Irdane Eifelian/Givetian stratotype, where the most important change in the ostracod fauna is related to the 40 cm-thick level of grey silty-marl located 10 cm below the boundary. However, this change is not indicative of an extinction event at this level. Three zones established on ostracods are recognized in the Frasnian and in the base of the Famennian of the Tafilalt.  相似文献   

10.
Complete, articulated starfish fossils are rare. However, more frequently encountered dissociated skeletal elements (ossicles) permit reliable taxonomic identification, making them a valuable data source for diversity estimates. Nearly 300 asteroid ossicles, collected from the middle Toarcian marls in western France can be assigned to five species. Four species and two genera are described: Comptoniaster vrinensis nov. sp. (Goniasteridae), Poncetaster crateri nov. gen. nov. sp. (Stauranderasteridae), Galbaster recurrans nov. gen. nov. sp. (Goniasteridae) and Pentasteria? liasica nov. sp. (Astropectinidae). The known diversity of Early Jurassic asteroids is increased from 12 to 16 species. These taxa illustrate the diversification of crown-group asteroids early in the Jurassic, following the Permo-Triassic crisis. They also reflect bias of the fossil record, and imply the existence of numerous ghost lineages in the evolutionary trees of extant groups. Variation in asteroid diversity across the “Seuil du Poitou” was driven by ecological constraints. The relative frequency (abundance of ossicles and diversity) of goniasterids and stauranderasterids increases in shallower environments. The Benthopectinidae, represented by Plesiastropecten hallovensis, occurred primarily from deep-shelf sediments. Similar ecological patterns are observed for more recent fossil and extant relatives, which further supports the idea of conservative evolution in post-Palaeozoic starfishes since the Early Jurassic.  相似文献   

11.
A Belouze  C Atallah 《Geobios》2003,36(3):241-273
New specimens from Cenomanian outcrops of Lebanon permit redescribtion of the first eel-like fossil fishes. Anguillavus bathshebaeHay, 1903 becomes synonymous with the type species A. quadripinnisHay, 1903. A new fossil eel with pelvic fins, Anguillavus mazeni nov. sp., is furthermore proposed. In the same way, the revision of Luenchelys minimus nov. gen., nov. sp., reveals some morphological variations at the specific level and a widespread biogeographical repartition which potentially can be important. This whole anatomical revision is a necessary basis for integrating these fossils into the Anguilliformes (Teleostei, Elopomorpha) and gives an idea of the plesiomorphic structural pattern of the order, in which the modern forms are particularly specialised.  相似文献   

12.
The originality of the sedimentary deposits and ammonite faunas in the jebel Bou Rharraf concerns “Ammonitico Rosso” facies, the westernmost known for the Pliensbachian, and a strong diversity of the Phylloceratida (Phylloceras, Calaiceras, Zetoceras, Partschiceras and Juraphyllites). The morphological disparity is also important in Galaticeras, Miltoceras and Tauromeniceras. If some taxa like Miltoceras taguendoufi and Mauretaniaceras elmii nov. gen., nov. sp. seem endemic to the High Atlas, most part of the Pliensbachien ammonites of the eastern High Atlas are classic for the southern margin of the western Tethys. Three genera (Callomoniceras, Appenninoceras, Mauretaniaceras) and three new species (Miltoceras involutum, Tropidoceras heterogeneum, Mauretaniaceras elmii) are described. An analysis using the “Discrete Cosine Transform” (DCT) method allows the better understanding of the morphospace of the rib patterns for the Fuciniceras from jebel Bou Rharraf. The biostratigraphy of the High Atlas is also improved with a set of 19 biohorizons for the Pliensbachian and the base of the Toarcian that are correlable with the Tethyan areas.  相似文献   

13.
Doryaspis groenhorgensis nov. sp. is a new pteraspidiform from the lower devonian of Spitsbergen. The genus Doryaspis is now considered as the most abundant pteraspidiform of the Wood Bay formation, with five described species. Moreover, the pteraspidiform diversity of this formation has been under rated all along the XXth century. A morpho-functional analysis of the Doryaspis generic characters (e.g. flat dorsal shield, ventral pseudorostrum, long cornual plates) allows to consider two possible mode of life. However, none of the pelagic or benthic mode of life is better supported than the other. The same analysis introduce some interpretative hypothesis on histology and moving of the Pteraspidiformes. The Pteraspidiformes diversity of Spitsbergen is important for further Devonian circum-arctic comparisons (e.g. siberian platform).  相似文献   

14.
Twelve species of the family Cyprididae were found in the Upper Miocene of the Turiec Basin, of which three are new - Herpetocypris denticulata nov. sp., H. pusilla nov. sp. et Psychrodromus janzi nov. sp. The occurrence of Mediocypris suggests that ostracods occupied the Turiec Basin since the Middle Miocene. The psychrophilic genera (Psychrodromus and Cavernocypris) provide evidence of cold springs around the lake. In the sediments studied, the Cyprididae are associated with other ostracods that characterise shallow aquatic habitats and a diverse community of both aquatic and terrestrial plants. The sexual paleo-populations of Heterocypris salina (Brady, 1868), Herpetocypris pusilla nov. sp. and Psychrodromus janzi nov. sp. are observed.  相似文献   

15.
L Taverne 《Geobios》2002,35(5):605
The osteology of Pseudanogmius maiseyi gen. and sp. nov., a marine teleost of the Upper Cretaceous of Kansas, is studied. This fish belongs to the order Tselfatiiformes and more particularly to the group with a more or less flat skull roof and with large, quadrangular and joined parietals. Pseudanogmius maiseyi, formerly named Anogmius sp. by Hay (1903), differs from Bananogmius and the other genera known in the order by three autapomorphies: an elongated and very narrow vomer, a peculiar relief of the toothed part of the parasphenoid, and transverse processes on the caudal vertebrae. Within the order, it shows a few evolved characters, such as the loss of the preural 1 hemal arch and of the sixth autogenous hypural and by the shortening of the preural 1 neural spine.  相似文献   

16.
A new species of DionideBarrande, Dionide mareki nov. sp., is described from siltstones of Llandeilo age in the Armorican Massif and north Portugal. The known geographical distribution of this species presents new evidence for the strong palaeobiogeographical relationship, during the Llandeilo, between the Valongo district (near Porto) and the Martigné-Ferchaud and Saint-Julien-de-Vouvantes synclinoriums south of Rennes.  相似文献   

17.
Three genera and seven species belonging to the subfamily Zigzagiceratinae (family Perisphinctidae) are described from the Lower Bathonian of France and Saudi Arabia. Intraspecific dimorphism is recognized. A revision of the genus Franchia proposed by Sturani (1967), based on the syntypes and new specimens from south‐east France, is presented. Franchia arkelli Sturani, Franchia subalpina sp. nov., Protozigzagiceras torrensi (Sturani), Protozigzagiceras tethycum sp. nov., Protozigzagiceras flexum sp. nov. and Protozigzagiceras densum sp. nov. are described from the Digne–Castellane region of south‐east France. Megazigzagiceras subarabicum, gen. et sp. nov. is described from the Dharma region of Saudi Arabia. The successive Early Bathonian species of Franchia and Protozigzagiceras herein identified in West Tethyan areas, as members of the Mediterranean–Caucasian Subrealm, formed lasting separate peramorphoclines characterized by increasing hydrodynamic coiling of the shell. In contrast, rapid proterogenesis originated and diversified the earliest Bathonian zigzagiceratin lineages, giving paedomorphic members, commonly neotenic and more scarcely progenetic. ProceritesSiemiradzkia seems to be the oldest zigzagiceratin member in the French Subalpine, Iberian and Lusitanian basins, branched off by paedomorphosis from leptosphinctins at the Bajocian–Bathonian transition. The Mediterranean–Caucasian genera Franchia, Zigzagiceras, Zigzagites and Wagnericeras branched from successive species of Protozigzagiceras, in turn, a direct derivative of Procerites. The oldest lineages of the clade Zigzagiceratinae evolved by iterative, rapid, paedomorphic changes and additional, lasting, peramorphic modifications during the Early Bathonian.  相似文献   

18.
The detailed study of the Miocene strata of Bonifacio has revealed an atypical Miogypsinid assemblage. In addition to the three already cited genera, Miogypsinoides, Miogypsina and Miolepidocyclina from this region, Miogypsinodella is for the first time represented by two new species (Mdella corsicana nov. sp. et Mdella pillaria nov.sp.). The stratigraphical ranges of each genus in the Miogypsinidae are not verified here. However, Mdes bantamensis is still present in the Upper Burdigalian and the genus Miogypsinoides is also present in the Lower Langhian. Six species of Miogypsina coexist in the Upper Burdigalian (M. tani, M. globulina, M. intermedia, M. cf. sabahensis, M. cushmani, M. mediterranea) and two species are present in the Lower Langhian (M. antillea, M. digitata). This distribution is apparently an example of palaeoendemism resulting from the geographic isolation and the rotation of the Corso-Sardinian block and also from the palaeogeographical and palaeoecological favourable environment during that time.  相似文献   

19.
A new genus and two new species, Salagouneura chimaira nov. gen. and nov. sp. and Phaneroneura minuta nov. sp., together with several other specimens of uncertain affinities, are herein assigned to the family Martynoviidae. This family was previously only known from the Lower Permian of Oklahoma and Kansas (USA). The new specimens have been discovered in the Salagou Formation (Permian; Hérault, France). Stratigraphical and palaeoecological implications of the occurrence of this family in the Salagou Formation are discussed. These discoveries seem correlated with similar palaeoenvironmental conditions between the Salagou Formation and the Midco Salt Lake Formation (Oklahoma).  相似文献   

20.
Ten species of trilobites belonging to 4 genera of the sub-family Asteropyginae DELO are described from the Devonian (Givetian-Frasnian) of Iran. Three of which are new: Neocalmonia lutensis nov. sp., Neocalmonia yazdii nov. sp. and Radiopyge sardarensis nov. sp. The study of this material have required the revision of Heliopyge sharudensis(PILLET, 1974) from the Givetian of the Eastern Alborz Mountains and of Neocalmonia quadricosta PILLET, 1969, type-species of the genus Neocalmonia, from the Frasnian of Afghanistan. The recognition of genera and species in common with the Givetian and the Frasnian of Afghanistan emphasizes the close relations between these two regions. The genera Bradocryphaeus, Heliopyge, Neocalmonia, Radiopyge, represented by related species, are likewise present in Iran, Afghanistan and Western Europe. Their presence confirms that these regions belong, during the Devonian, to the North Gondwanian domain.  相似文献   

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