Interprétation paléogéographique des données palynologiques du site du Paléolithique supérieur de Mezhyrich (Ukraine)

The results of palynological study of the Upper Paleolithic Mezhyrich site in central Ukraine are presented. Four local pollen zones were identified. The results of the palynological investigations allow us to hypothesize that the plant cover during Upper Paleolithic had a mosaic structure. The pollen record shows the presence of a few tree species with the predominance of herbaceous plants. We suggest that the river valleys and other local favorable sites were natural refugia where forest elements could survive even during the Last Glacial Maximum. These favorable landscapes to the existence of prehistoric hunters may have persisted during the Last Pleniglacial.     

Analyse biostratigraphique et paléontologique de l'Albien marin d'Estremadura (Portugal)

The marine Albain from Estremadura is splited up into four Orbitolinidae zones, adjusted to biostratigraphic scales from mesogean province: zone with Orbitolina (Mesorbitolina) minuta (lower to middle Albian); zone with Neorbitolinopsis conulus (base of upper Albian); zone with Orbitolina (Orbitolina) concava (top of upper Albian) and zone with Orbitolina (Orbitolina) duranddelgai (Vraconian). The vertical extension of the main fossils is replaced in the framework of these zones. The most interesting species for biostratigraphy, paleoecology or taxinomy are summarily described.     

Nanisme écologique de deux espèces d'échinides irréguliers dans l'Hauterivien de la région de Castellane (Alpes-de-Haute-Provence)

Three species of irregular see-urchins form the settlement of a marly level (lower Hauterivian) of the Castellane area. Two of them are strongly smaller than the norm. Their stunting is prouved by ontogenic, mecanical, sedimentological and ecological arguments. The ecological grounds of stunting are discussed.     

La cicatrisation cryptalgaire des diastèmes en tantqu'indicateur paléogéographique: Exemple de la Lettenkohle

Lettenkohle's lagoonal sediments of eastern Franceshow cryptalgal laminites close to diastems between two types of sequences: fluviolacustrine or «mediolittoral (french terminology, Pérès, 1966).The transition between inferior marine and middlenon-marine formations coincided with the development of stromatolitic structures, which molded and preserved the dessicated gypsiferous dolomicrites of inferior Lettenkohle.This phenomena is repeated with an inverse trend,by the way marking transition from middle to upper Lettenkohle, prior to the installation of variegated clays of inferior Keuper.     

Faunes d'oiseaux du pléistocène de France: Systématique, évolution et adaptation,interprétation paléoclimatique

Statistical comparison between bird populations from Lower and Middle Pleistocene and present ones makes it possible to demonstrate evolutionnary shifts such as increase in size or, on the contrary, decrease in size in some lineages and to discover some species or subspecies already found in Central Europe, in layers of the same epoch. In some other lineages the observed variations seem to be regarded as possible adaptations to local geographical conditions.Moreover the study of the birds contributes richly to the reconstitution of climates and biotops. The percentage variations of «cold birds in a given site makes it possible to confirm climatic fluctuations already discovered by other methods of study.     

Scolécodontes,assemblage et appareil de vers annelidespolychetes errantes de l'aptien de la région d'Agadir,Maroc

From the Aptian scolecodonts inventory of the Agadir area one jaw apparatus and one joining of polychetes are reconstructed. One is the elementary species Schistomeringos expectatusSzaniawski & Gazdzicki, 1978, the oldest representative of the multielementary family Dorvilleidae Chamberlin 1919. The other is a representative of either the multielementary families Atraktoprionidae Kielan Jaworowska 1966 emend. Kozur, 1970 or Arabellidae Hartman 1944. This joining is considered as an hypothesis since all the necessary criteria, defined by H. Szaniawski & A. Gazdzicki 1978, are not all present.     

Signification paléoécologique et paléogéographique des bivalves du Carbonifère inférieur du bassin d’Ancenis (Massif armoricain)

Palaeoecological and palaeogeographical inferences from Early Carboniferous bivalves of the Ancenis Basin (Variscan belt, France). In the basal part of the Ancenis Formation, of Dinantian age, greenish to purple mudstones display a few bivalves, assigned to the genera Lithophaga, Modiolus, and Naiadites. Because Naiadites is considered to be a non-marine bivalve, and is only previously reported in Scotland in Dinantian rocks, a brackish environment can be assumed for the Ancenis Basin during the Early Carboniferous. To cite this article: M. Ballèvre, H. Lardeux, C. R. Palevol 4 (2005).     

Echinodermes (Homalozoa: Cornuta et Mitrata) nouveaux pour l'Ordovicien du Massif Armoricain et conséquences paléogéographiques

Two specific genera of Bohemian Llanvirn(Sarka Formation), Reticulocarpos and Lagynocystis have been recognized in Traveusot, le Pissot and Pierre Melière Formations (Llanvirn and Llandeilo of the Armorican Massif). Though three species are new (R. pissotensis, R. sp., Lagynocystis sp.) this discovery once more underlines the relationships between Bohemia and Armorican Massif during this period.     

L'âge du complexe récifal des côtes de meuse entre verdun et commercy et la stratigraphie de l'oxfordien dans l'est du bassin de Paris

The question of the age of «Hauts de Meuse coral rag is studied again using new faunas of brachiopods and ammonites collected above, below and inside the coral rag. Ammonites fauna of the well known «Calcaires de Creuë is revised. Results obtained agree closely.The «Hauts de Meuse coral rag grew up during Middle Oxfordian time; and extend part of the Plicatilis zone (Antecedens Subzone) and the whole Transversarium Zone up to the basis of the Bifurcatus Zone, for the first time identified in Lorraine. So it span a short depositional time, about 1 MY, with a high deposition rate, the thickness of the coral rag being more than 100 meters, reaching 150 meters in Saint-Mihiel area. Towards SE, on the other side of the Marne Gap, the sudden change into basinal facies go with a reducing of thickness and deposition rate.Upper Oxfordian deposits show a relative uniformity of facies and thickness. At the top of Middle Oxfordian limestones, the age of the discontinuity and the Sequanian renewal of deposition is basal Bifurcatus Zone. Erosional renewal and terrigeneous deposits are a wide spread event by the beginning of Upper Oxfordian.In the paleontological part, species upon which are based new ages and interpretations are only figured, except the species new or with new paleontological data, which are described. Type specimen of Perisphinctes mosensisBayle, from the «Calcaires de Creuë, is described and photographically figured for the first time.     

13C NMR des alcaloïdes des Strychnos: Les dérivés de l'harmane et de l'usambarensine

¹³C NMR spectra of some tertiary and quaternary indole alkaloids are recorded and the signals assigned. Graphic interpretation of off-resonance spectra and substituent shielding effects together with the effect of N_b-methylation are utilized in the spectral interpretation.     

Évolution des constituants biochimiques des principaux compartiments de l'oursin Arbacia lixula (L.) au cours d'un cycle sexuel et effets d'un jeûne de courte durée au cours de la maturation sexuelle

The importance of the different compartments of the body in Arbacia lixula (L.) has been investigated by means of short duration starvation experiments carried out during periods of sexual rest and of maturity. The oxygen consumption was also determined during those two phases of the sexual cycle. The amount of calories furnished by the transformation of the biochemical constituents where significant lowering of the levels has been noted, cover largely the needs of standard metabolism.Annual variations of the protein, lipid and carbohydrate percentage in the 3 compartments: test, gut, gonads, have been followed from September 1973 to May 1974. An increase in the proteins is observed in the gonads from the beginning of growth to maturity, as well as an increase in the carbohydrates and the lipids during the period of growth. The carbohydrates of the gut increase in winter and the lipids in spring.An estimate has been made of the quantity of energy liberated by the 3 compartments on the death of the sea urchin.     

Les ostracodes et l'évolution paléogéographiqueau quaternaire récent du site d'Ashtart (golfe de gabès,tunisie orientale)

enTwenty-seven samples have been collected in AshtartBasin (Pelagian Sea), along the core KST 100. Studies on ostracods species enables us to recognize four main associations from - 27 000 years to the Recent; the first can be linked to the Würm III regression and the other ones to the Versilian transgression.     

Mise à jour taxonomique et répartition des puces du genre Ctenophthalmus Kolenati 1856 en région paléarctique occidentale (Insecta : Siphonaptera : Ctenophthalmidae)

Summary. Taxonomic update and geographic distribution of fleas of the genus Ctenophthalmus Kolenati 1856 in the Western Palearctic Region (Insecta: Siphonaptera: Ctenophthalmidae). Among fleas (Siphonaptera), the genus Ctenophthalmus is the one that comprises the largest number of taxa and is also characterized by a large geographical range. Here, we present a taxonomic revision of the Western Paleartic subgenera, groups, species and subspecies. We recognized a total of 143 taxa (57 species and 86 subspecies). These taxa are clustered into 23 groups of species, which fall into seven of the 16 subgenera of the genus Ctenophthalmus. According to Hopkins & Rothschild (1966), the subgenus Ctenophthalmus would only include the agyrtes group, itself divided into subgroups. We decided to raise these subgroups to group status to clarify taxonomic relationships within the subgenus Ctenophthalmus. Within this subgenus, the arvernus group is renamed baeticus, the fransmiti group is confirmed, and the egregius group is created. For each taxon, we provided information on geographical distribution, mammalian hosts, and host specificity.     

Les ostracodes et foraminifères associés des dépôts de l’Éocène moyen et supérieur de la coupe de Jebel Serj (Tunisie centrale). Intérêt biostratigraphique,paléoécologique et paléobiogéographique

The ostracod fauna collected from the Cherahil formation that crops out at the Jebel Serj section (central Tunisia) contains 24 species belonging to 12 genera. These ostracods are associated with 9 genera of benthic Foraminifera (including 4 Nummulites species) and 7 genera of planktonic Foraminifera. The biostratigraphic study of ostracod assemblages results to the recognition of 6 biozones which are correlated with Lutetian-Priabonian. The Shannon Weaver, Margalef and equitability indices point to internal platform netritic conditions, with minor fluctuations in depth and oxygenation. The palaeobiogeographic distribution of ostracod species found in the study area of Central of Tunisia establishes a good connexion with the basins developed in Northern Africa (Tunisia, Algeria, Libya and Mauritania) and the Middle East (Egypt and Jordan).     

A propos des fossiles du Pliocène d'Aguilas(Sud d'Almeria,Espagne) découverte de Cirripèdes operculés (Crustacés) et discussion sur l'étho-écologie des formes épizoaires

A benthic taphocoenose from the Pliocene I of Aguilas (provinces of Murcia-Almeria, Southern Spain) conseals four Cirripedia (family of BalanidaeLeach): Balanus (Balanus) perforatus angustusGmelin, B. (B.) amphitriteDarwin, B. (Megabalanus) tintinnabulum tintinnabulumLinné and Creusia (Withersia) phryxaPajaud.The study of the last one is especially interestingfrom an ecological point of view. Indeed, all species, well-known in the Creusia-Pyrgoma group are more or less dependent on Anthozoa since Miocene, the cuplike basis of their shell buried on corallites. But not corallites were gathered in the deposits of Aguilas and the morphology of Creusia phryxa leads us to believe a fixation of the shell on a flaccid substratum. From which we may suppose that the host of this Cirriped was perhaps an Actiniaria.     

Les remplissages sédimentaires des coquilles de céphalopodes triasiques. Mécanismes et intérêt paléoécologique

Experiments have been carried out in laboratory onplastic cephalopod models in order to study most aspects of sedimentary shell filling of Ceratites and Nautilus from the German Upper Muschelkalk. In most cases the shells had a horizontal position when being filled by the sediment. The exception of filling in upright position has been observed mainly for Ceratites nodosus nodosus (Bruguière, 1792), Acanthoceratites spinosus (Philippi, 1901) except the species A. spinosus penndorfi (Rothe, 1955), Acanthoceratites evolutus (Philippi, 1901) and the nautilus Germanonautilus bidorsatus (Schlotheim, 1804); it is due to the width of their shells. In no case the sediment filling of cephalopod shells gives information about the depth of the depositional environment. On the other hand it is a good indicator of the waving occurring on the sea floor and the reworking of the sediment.     

Figures sédimentaireset traces d'origine biologique du Trias moyen de la bordure orientale du Massif Central signification sédimentologique et paléoécologique

The sandstones with foot-prints of reptiles and saltcasts from the Middle Triassic of the eastern border of the Massif Central (France) show a striking reptilian ichnofauna. The numerous sedimentary figures and trace fossils which are described here allow to deduce the following characteristics of the depositional environment: shallow water, lower flow regime, periodical increase of salinity. The reptiles used to pass through that environment where numerous stretches of water alternated with emerged, plant overgrown areas.