Des serpents (Reptilia,Squamata) de type nord-américain dans le Miocène Français. Évolution parallèle ou dispersion?

The French Miocene (Orleanian and Astaracian) yielded five new species of snakes referable to four genera from the Neogene or Recent of North America: Texasophis meini nov. sp., Paleoheterodon arcuatus nov. sp., Neonatrix europaea nov. sp., Neonatrix crassa nov. sp. (Colibridae) and Micrurus gallicus nov. sp. («Elapidae). It is suggested that Micrurus and the previously described boid snake Albaneryx from the French Miocene probably represent lineages that originated in North America and reached Europe by way of Asia. Paleoheterodon and Neonatrix could have originated in Asia and subsequently reached Europe on one hand and North America on the other. Texasophis may have originated in North America and followed the same route as Micrurus and Albaneryx, but an alternative hypothesis is that it originated in Asia and spread toward Europe and North America in the same manner as Paleoheterodon and Neonatrix.     

Les ongulés en périgord et Nord-Ouest du Quercydurant le würm III. Chronoclimatologie,paléobiogéographie,palethnologie

The studies of Ungulate associations present in Würm III deposits of Southwest France lead to state biological paleoenvironments and paleoclimates more precisely. The second climatic phasis brought to light by H. Laville in Perigord seems cold and dry and the third one (Arcy) would be the most temperate and humid phasis during the Würm III period. Two posterior climatic ameliorations (fifth phasis = «Kesselt and seventh phasis = Tursac) are separated by a colder period. From the eighth phasis, a climatic threshold is crossed; paleontological as well as geological and palynological studies show the establishment of global cold conditions which would continue after Würm III–IV «interstadial (Laugerie). This one looks like a minor humid oscillation.Although data come from geographically close sites, clear differences appear between contemporary faunal associations. In Perigord, Ungulate associations strongly vary during the first seven phasis whereas in Northwest Quercy, in Auniac plain, Reindeer dominates all along this period.Lastly, comparisons between the results of paleontological,geological and palynological studies enable us to approach the question of the game choice made by prehistoric men. The perigordian men who inhabit La Ferrassie rockshelter during the sixth climatic phasis preferentially hunt Reddeer. They deliberately give up hunting other Ungulates yet well represented in contemporary levels of not distant sites.     

The origin of Jurassic reefs: Current research developments and results

Summary In order to elucidate the control of local, regional and global factors on occurrence, distribution and character of Jurassic reefs, reefal settings of Mid and Late Jurassic age from southwestern Germany, Iberia and Romania were compared in terms of their sedimentological (including diagenetic), palaeoecological, architectural, stratigraphic and sequential aspects. Upper Jurassic reefs of southern Germany are dominated by siliceous sponge—microbial crust automicritic to allomicritic mounds. During the Oxfordian these form small to large buildups, whereas during the Kimmeridgian they more frequently are but marginal parts of large grain-dominated massive buildups. Diagenesis of sponge facies is largely governed by the original composition and fabric of sediments. The latest Kimmeridgian and Tithonian spongiolite development is locally accompanied by coral facies, forming large reefs on spongiolitic topographic elevations or, more frequently, small meadows and patch reefs within bioclastic to oolitic shoal and apron sediments. New biostratigraphic results indicate a narrower time gap between Swabian and Franconian coral development than previously thought. Palynostratigraphy and mineralostratigraphy partly allow good stratigraphic resolution also in spongiolitic buildups, and even in dolomitised massive limestones. Spongiolite development of the Bajocian and Oxfordian of eastern Spain shares many similarities. They are both dominated by extensive biostromal development which is related to hardground formation during flooding events. The Upper Jurassic siliceous sponge facies from Portugal is more localised, though more differentiated, comprising biostromal, mudmound and sponge-thrombolite as well as frequent mixed coral-sponge facies. The Iberian Upper Jurassic coral facies includes a great variety of coral reef and platform types, a pattern which together with the analysis of coral associations reflects the great variability of reefal environments. Microbial reefs ranging from coralrich to siliceous sponge-bearing to pure thrombolites frequently developed at different water depths. Reef corals even thrived within terrigeneous settings. In eastern Romania, small coral reefs of various types as well as larger siliceous sponge-microbial crust mounds grew contemporaneously during the Oxfordian, occupying different bathymetric positions on a homoclinal ramp. Application of sequence stratigraphic concepts demonstrates that onset or, in other cases, maximum development of reef growth is related to sea level rise (transgressions and early highstand) which caused a reduction in allochthonous sedimentation. The connection of reef development with low background sedimentation is corroborated by the richness of reefs in encrusting organisms, borers and microbial crusts. Microbial crusts and other automicrites can largely contribute to the formation of reef rock during allosedimentary hiatuses. However, many reefs could cope with variable, though reduced, rates of background sedimentation. This is reflected by differences in faunal diversities and the partial dominance of morphologically adapted forms. Besides corals, some sponges and associated brachiopods show distinct morphologies reflecting sedimentation rate and substrate consistency. Bathymetry is another important factor in the determination of reefal composition. Not only a generally deeper position of siliceous sponge facies relative to coral facies, but also further bathymetric differentiation within both facies groups is reflected by changes in the composition, diversity and, partly, morphology of sponges, corals, cementing bivalves and microencrusters. Criteria such as authigenic glauconite, dysaerobic epibentic bivalves,Chondrites burrows or framboidal pyrite in the surrounding sediments of many Upper Jurassic thrombolitic buildups suggest that oxygen depletion excluded higher reefal metazoans in many of these reefs. Their position within shallowing-upwards successions and associated fauna from aerated settings show that thrombolitic reefs occurred over a broad bathymetric area, from moderately shallow to deep water. Increases in the alkalinity of sea water possibly enhanced calcification. Reefs were much more common during the Late Jurassic than during the older parts of this period. Particularly the differences between the Mid and Late Jurassic frequencies of reefs can be largely explained by a wider availability of suitable reef habitats provided by the general sea level rise, rather than by an evolutionary radiation of reef biota. The scarcity of siliceous sponge reefs on the tectonically more active southern Tethyan margin as well as in the Lusitanian Basin of west-central Portugal reflects the scarcity of suitable mid to outer ramp niches. Coral reefs occurred in a larger variety of structural settings. Upper Jurassic coral reefs partly grew in high latitudinal areas suggesting an equilibrated climate. This appears to be an effect of the buffering capacity of high sea level. These feedback effects of high sea level also may have reduced oceanic circulation particularly during flooding events of third and higher order, which gave rise to the development of black shales and dysaerobic thrombolite reefs. Hence, the interplay of local, regional and global factors caused Jurassic reefs to be more differentiated than modern ones, including near-actualistic coral reefs as well as non-actualistic sponge and microbial reefs.     

Species of Bursaphelenchus Fuchs, 1937 (Nematoda: Parasitaphelenchidae) and other nematode genera associated with insects from Pinus pinaster in Portugal

Insects associated with maritime pine, Pinus pinaster, in Portugal were collected and screened for the presence of Bursaphelenchus species. Nematodes were identified using Internal Transcribed Spacers‐Restriction Fragment Length Polymorphism (ITS‐RFLP) analysis of dauer juveniles and morphological identification of adults that developed from dauer juveniles on fungal cultures or on cultures in pine wood segments at 26°C. Several associations are described: Bursaphelenchus teratospicularis and Bursaphelenchus sexdentati are associated with Orthotomicus erosus; Bursaphelenchus tusciae, B. sexdentati and/or Bursaphelenchus pinophilus with Hylurgus ligniperda and Bursaphelenchus hellenicus with Tomicus piniperda, Ips sexdentatus and H. ligniperda. An unidentified Bursaphelenchus species is vectored by Hylobius sp. The previously reported association of Bursaphelenchus xylophilus with Monochamus galloprovincialis was confirmed. The association of Bursaphelenchus leoni with Pityogenes sp. is not definitively established and needs further studies for clarification. Other nematode genera besides Bursaphelenchus were found to be associated with the insects sampled, including two different species of Ektaphelenchus, Parasitorhabditis sp., Parasitaphelenchus sp., Contortylenchus sp. and other unidentified nematodes. The Ektaphelenchus species found in O. erosus is morphologically similar to B. teratospicularis found in the same insect; adults of both the species are found in cocoon‐like structures under the elytra of the insects.     

Do distributional shifts of northern and southern species of algae match the warming pattern?

Well-documented changes in species abundances and distributions coinciding with global warming have been increasing during recent years. A trend of raising sea-surface temperature has also been observed along the Portuguese coast which could affect intertidal species' ranges. The present study aimed at evaluating the direction and intensity of distribution changes of macroalgae in the area. The last 50-year trend of coastal air and sea temperature was reassessed, providing an accurate estimate of the warming process. Information on species' range shifts was obtained by comparing data from recent resurveys with historical records of algal distributions collected during the 1950s and 1960s. Although a prevalence of northward migrations was anticipated, this work showed a marked difference in the average direction of changes between cold- and warm-water species. Cold-water species, when considered together, showed no particular shifting trend, because the number of species that shifted north or south was the same. Contrarily, all shifting warm-water species expanded their range northwards. Therefore, generalizations about poleward range shifts due to increasing temperature should be made with caution.     

Influence du type de culture et de l'antécédent cultural sur les déplacements des adultes de la pyrale du maïs Ostrinia nubilalis

Résumé Au cours de l'été 1983 dans un agrosystème de Charente (Nord du Bassin Aquitain), les auteurs ont utilisé la technique du piégeage lumineux associée à des lâchers d'insectes marqués. Afin de mimer les émergences possibles des papillons à partir de chenilles hivernantes, les insectes colorés étainent lâchés dans une parcelle de blé (Triticum) (à antécédent cultural maïs), à égale distance de 4 pièges disposés dans 4 parcelles adjacentes. Les captures d'insectes colorés montrent clairement que les femelles quittent le blé et se dirigent vers le maïs, confirmant par là le rôle de l'antécédent cultural sur les infestations annuelles. Les captures d'insectes sauvages indiquent à cette époque une prédominance des mâles due probablement à la protandrie d'environ 8 jours chez l'espèce et à une mobilité naturelle supérieure à celle des femelles. Les implications écologiques et agronomiques de ces déplacements sont discutées et un schéma d'explication des différents types de mouvements des papillons de pyrale: déplacements d'émergence et déplacements quotidiens alternatifs, est proposé.     

Analyse en olfactomètre de l'attraction des larves d‘Acrolepiopsis assectella par des substances allélochimiques

Un olfactomètre a deux flux d'air parallèles comportant un fil en Y est décrit et utilisé pour édudier l'attraction des larves néonates et de 5ème stade de la teigne du poireau par la plante-hôte, les composés volatils soufrés qu'elle émet et quelques odeurs originaires d'autres végétaux. Le poreau, les disulfures, les thiosulfinates et les thiosulfonates sont attractifs. L'action des composés soufrés dépend de la concentration utilisée et du stade larvaire. Les résultats sont comparés à ceux obtenus antérieurement sur la phagostimulation larvaire et sur l'attraction des adultes.     

Phylogenetic analysis of the calvaria of Homo floresiensis

Because until 2006 the Liang Bua human fossil remains were not available to the entire paleoanthropological community, the taxonomic position of Homo floresiensis was only a matter of opinion in publications. From the beginning, two schools of thought prevailed, and this situation persists today. One purports that the Liang Bua human series belongs to a local modern human (Homo sapiens sapiens) with anatomical particularities or pathologies that may be due to insular isolation/endogamy. The second argues in favour of the existence of a new species that, depending on the authors, is either a descendant of local Homo erectus, or belongs to a much more basal taxon, closer to archaic Homo or to australopithecines. Because there are no postcranial remains confidently attributed to Homo erectus in the fossil record, and because the Homo erectus type specimen is a single and partial calvaria, a cladistic analysis was undertaken using both nonmetric morphological features and metrics of the calvariae of human fossil specimens including LB1 to test if it belongs to this taxon. Our results indicate that LB1 is included in the Homo erectus clade.     

Floristic changes of epiphytic flora in the Metropolitan Lisbon area between 1980–1981 and 2010–2011 related to urban air quality

Epiphytic lichen and bryophyte Floristic Richness (FR) and distribution were investigated in Lisbon and the adjacent southern riverbank, in the centre-west of Portugal within the Lisbon Metropolitan Area (LMA). Field studies were carried out in the years 2010–2011 to replicate research conducted 30 years ago in 1980–1981.Compared to previous surveys, we confirm that the overall environmental condition has largely improved, with higher epiphyte richness. The two areas have been recolonized during the last 30 years by sensitive species mainly due to changes in SO₂ levels. However, the traffic-related NO₂ and dust deposition have become the main pollutants and the increase of nitrophilous and saxicolous/terricolous taxa reflects this influence. But, besides air pollution, the important variable affecting the epiphytic flora of LMA, currently updated to more than 200 taxa, is the influence of arborisation system type, road type and road proximity of the new surveys, in addition to urbanization (calculated in an Index of Human Impact – IHI).According to their current epiphyte diversity, with Floristic Richness (RF) ranging from 4 to more than 90 taxa (lichens and bryophytes), five zones were identified in LMA and related with air quality.As a conclusion, significant changes in the Floristic Richness (FR) were observed over the past 30 years, not only the value but also the spatial pattern which differs greatly between the two areas, linked significantly with air quality and other human influences.Due to the few number of available air quality monitoring stations, in particularly for NO₂ values, the important contributions of epiphytic flora in defining the distribution range and spatial patterns of urban disturbance imply that FR may be a practical and useful indicator of air quality in LMA.