351 research outputs found

    Sharks of the order Carcharhiniformes from the British Coniacian, Santonian and Campanian (Upper Cretaceous).

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    Bulk sampling of phosphate-rich horizons within the British Coniacian to Campanian (Upper Cretaceous) yielded very large samples of shark and ray teeth. All of these samples yielded teeth of diverse members of the Carcharhiniformes, which commonly dominate the fauna. The following species are recorded and described: Pseudoscyliorhinus reussi (Herman, 1977) comb. nov., Crassescyliorhinus germanicus (Herman, 1982) gen. nov., Scyliorhinus elongatus (Davis, 1887), Scyliorhinus brumarivulensis sp. nov., ? Palaeoscyllium sp., Prohaploblepharus riegrafi (MĂŒller, 1989) gen. nov., ? Cretascyliorhinus sp., Scyliorhinidae inc. sedis 1, Scyliorhinidae inc. sedis 2, Pteroscyllium hermani sp. nov., Protoscyliorhinus sp., Leptocharias cretaceus sp. nov., Palaeogaleus havreensis Herman, 1977, Paratriakis subserratus sp. nov., Paratriakis tenuis sp. nov., Paratriakis sp. indet. and ? Loxodon sp. Taxa belonging to the families ?Proscylliidae, Leptochariidae, and Carcharhinidae are described from the Cretaceous for the first time. The evolutionary and palaeoecological implications of these newly recognised faunas are discussed

    Sensory cutaneous papillae in the sea lamprey (Petromyzonmarinus L.) : I. Neuroanatomy and physiology

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    Molecules present in an animal's environment can indicate the presence of predators,food, or sexual partners and consequently, induce migratory, reproductive, foraging,or escape behaviors. Three sensory systems, the olfactory, gustatory, and solitarychemosensory cell (SCC) systems detect chemical stimuli in vertebrates. While agreat deal of research has focused on the olfactory and gustatory system over theyears, it is only recently that significant attention has been devoted to the SCC sys-tem. The SCCs are microvillous cells that were first discovered on the skin of fish,and later in amphibians, reptiles, and mammals. Lampreys also possess SCCs that areparticularly numerous on cutaneous papillae. However, little is known regarding theirprecise distribution, innervation, and function. Here, we show that sea lampreys(Petromyzon marinus L.) have cutaneous papillae located around the oral disk, nostril,gill pores, and on the dorsal fins and that SCCs are particularly numerous on thesepapillae. Tract-tracing experiments demonstrated that the oral and nasal papillae areinnervated by the trigeminal nerve, the gill pore papillae are innervated by branchialnerves, and the dorsal fin papillae are innervated by spinal nerves. We also character-ized the response profile of gill pore papillae to some chemicals and showed thattrout-derived chemicals, amino acids, and a bile acid produced potent responses.Together with a companion study (Suntres et al., Journal of Comparative Neurology,this issue), our results provide new insights on the function and evolution of the SCCsystem in vertebrates

    Skeletal Morphology of Opius dissitus and Biosteres carbonarius (Hymenoptera: Braconidae), with a Discussion of Terminology

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    The Braconidae, a family of parasitic wasps, constitute a major taxonomic challenge with an estimated diversity of 40,000 to 120,000 species worldwide, only 18,000 of which have been described to date. The skeletal morphology of braconids is still not adequately understood and the terminology is partly idiosyncratic, despite the fact that anatomical features form the basis for most taxonomic work on the group. To help address this problem, we describe the external skeletal morphology of Opius dissitus Muesebeck 1963 and Biosteres carbonarius Nees 1834, two diverse representatives of one of the least known and most diverse braconid subfamilies, the Opiinae. We review the terminology used to describe skeletal features in the Ichneumonoidea in general and the Opiinae in particular, and identify a list of recommend terms, which are linked to the online Hymenoptera Anatomy Ontology. The morphology of the studied species is illustrated with SEM-micrographs, photos and line drawings. Based on the examined species, we discuss intraspecific and interspecific morphological variation in the Opiinae and point out character complexes that merit further study

    The Butterfly Fauna Of The Italian Maritime Alps:Results Of The «Edit» Project

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    Bonelli, Simona, Barbero, Francesca, Casacci, Luca Pietro, Cerrato, Cristiana, Balletto, Emilio (2015): The butterfly fauna of the Italian Maritime Alps: results of the EDIT project. Zoosystema 37 (1): 139-167, DOI: 10.5252/z2015n1a6, URL: http://dx.doi.org/10.5252/z2015n1a

    Facilitating the development of controlled vocabularies for metabolomics technologies with text mining

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    BACKGROUND: Many bioinformatics applications rely on controlled vocabularies or ontologies to consistently interpret and seamlessly integrate information scattered across public resources. Experimental data sets from metabolomics studies need to be integrated with one another, but also with data produced by other types of omics studies in the spirit of systems biology, hence the pressing need for vocabularies and ontologies in metabolomics. However, it is time-consuming and non trivial to construct these resources manually. RESULTS: We describe a methodology for rapid development of controlled vocabularies, a study originally motivated by the needs for vocabularies describing metabolomics technologies. We present case studies involving two controlled vocabularies (for nuclear magnetic resonance spectroscopy and gas chromatography) whose development is currently underway as part of the Metabolomics Standards Initiative. The initial vocabularies were compiled manually, providing a total of 243 and 152 terms. A total of 5,699 and 2,612 new terms were acquired automatically from the literature. The analysis of the results showed that full-text articles (especially the Materials and Methods sections) are the major source of technology-specific terms as opposed to paper abstracts. CONCLUSIONS: We suggest a text mining method for efficient corpus-based term acquisition as a way of rapidly expanding a set of controlled vocabularies with the terms used in the scientific literature. We adopted an integrative approach, combining relatively generic software and data resources for time- and cost-effective development of a text mining tool for expansion of controlled vocabularies across various domains, as a practical alternative to both manual term collection and tailor-made named entity recognition methods

    Classification of Camellia (Theaceae) Species Using Leaf Architecture Variations and Pattern Recognition Techniques

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    Leaf characters have been successfully utilized to classify Camellia (Theaceae) species; however, leaf characters combined with supervised pattern recognition techniques have not been previously explored. We present results of using leaf morphological and venation characters of 93 species from five sections of genus Camellia to assess the effectiveness of several supervised pattern recognition techniques for classifications and compare their accuracy. Clustering approach, Learning Vector Quantization neural network (LVQ-ANN), Dynamic Architecture for Artificial Neural Networks (DAN2), and C-support vector machines (SVM) are used to discriminate 93 species from five sections of genus Camellia (11 in sect. Furfuracea, 16 in sect. Paracamellia, 12 in sect. Tuberculata, 34 in sect. Camellia, and 20 in sect. Theopsis). DAN2 and SVM show excellent classification results for genus Camellia with DAN2's accuracy of 97.92% and 91.11% for training and testing data sets respectively. The RBF-SVM results of 97.92% and 97.78% for training and testing offer the best classification accuracy. A hierarchical dendrogram based on leaf architecture data has confirmed the morphological classification of the five sections as previously proposed. The overall results suggest that leaf architecture-based data analysis using supervised pattern recognition techniques, especially DAN2 and SVM discrimination methods, is excellent for identification of Camellia species

    Biology and conservation of freshwater bivalves : past, present and future perspectives

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    Freshwater bivalves have been highly threatened by human activities, and recently their global decline has been causing conservational and social concern. In this paper, we review the most important research events in freshwater bivalve biology calling attention to the main scientific achievements. A great bias exists in the research effort, with much more information available for bivalve species belonging to the Unionida in comparison to other groups. The same is true for the origin of these studies, since the publishing pattern does not always correspond to the hotspots of biodiversity but is concentrated in the northern hemisphere mainly in North America, Europe and Russia, with regions such as Africa and Southeast Asia being quite understudied. We also summarize information about past, present and future perspectives concerning the most important research topics that include taxonomy, systematics, anatomy, physiology, ecology and conservation of freshwater bivalves. Finally, we introduce the articles published in this Hydrobiologia special issue related with the International Meeting on Biology and Conservation of Freshwater Bivalves held in 2012 in Bragancža, Portugal.We would like to express our gratitude to our sponsors and institutions, especially to the Polytechnic Institute of Braganca for all the logistic support. We acknowledge all keynote speakers, authors, session chairpersons and especially to all attendees whose contributions were fundamental for the success of this meeting. We would also like to thank all referees of this special issue and to Koen Martens, Editor-in-Chief of Hydrobiologia, for all the valuable comments and suggestions. The chronogram was built with the help of the expert opinion of fellow colleagues Rafael Araujo, Arthur Bogan, Kevin Cummings, Dan Graf, Wendell Haag, Karl-Otto Nagel and David Strayer to whom we are very grateful. The authors acknowledge the support provided by Portuguese Foundation for Science and Technology (FCT) and COMPETE funds-projects CONBI (Contract: PTDC/AAC-AMB/117688/2010) and ECO-IAS (Contract: PTDC/AAC-AMB/116685/2010), and by the European Regional Development Fund (ERDF) through the COMPETE, under the project "PEst-C/MAR/LA0015/2011"

    Phylogeny of the Aplousobranchia (Tunicata: Ascidiacea)

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