The Experts below are selected from a list of 360 Experts worldwide ranked by ideXlab platform

Deeleman-reinhold Christa - One of the best experts on this subject based on the ideXlab platform.

Sergio Antonio Vanin - One of the best experts on this subject based on the ideXlab platform.

  • A new species of Pacholenus Schoenherr from southeastern Brazil (Coleoptera, Curculionidae, Molytinae), and new occurrences of species of the genus
    Universidade de São Paulo, 2008
    Co-Authors: Sergio Antonio Vanin
    Abstract:

    A new species of Pacholenus Schoenherr from southeastern Brazil (Coleoptera, Curculionidae, Molytinae), and new occurrences of species of the genus. Pacholenus monteiroi sp. nov. (type-locality Brazil, Rio de Janeiro state, Carapebus, Parque Nacional da Restinga de Jurubatiba) is described and illustrated. The weevil develops as a stem gall-former in Calyptranthes brasiliensis Spreng (Myrtaceae). The new species is easily distinguished from the other five known of the genus by the presence of a prominent supra-ocular ridge. An updated key for identification for all species of Pacholenus is provided. Three species of Pacholenus are presently recorded for the states of Rio de Janeiro and São Paulo; P. pelliceus and P. monteiroi occur in both states, while P. Penicillus is only known from Rio de Janeiro; P. hispidus occurs in São Paulo, being the most widespread species of the genus, ranging from Minas Gerais south to Santa Catarina.Nova espécie de Pacholenus Schoenherr do sudeste do Brasil (Coleoptera, Curculionidae, Molytinae), e novas ocorrências de espécies do gênero. Pacholenus monteiroi sp. nov. (localidade-tipo Brasil, Estado do Rio de Janeiro, Carapebus, Parque Nacional da Restinga de Jurubatiba) é descrita e ilustrada. Esse gorgulho se desenvolve em galhas caulinares de Calyptranthes brasiliensis Spreng (Myrtaceae). A nova espécie é facilmente distinta das outras cinco conhecidas do gênero devido à presença de uma crista supra-ocular proeminente. Uma chave atualizada para identificação das espécies de Pacholenus é fornecida. Três espécies de Pacholenus ocorrem nos estado do Rio de Janeiro e São Paulo; P. pelliceus e P. monteiroi ocorrem em ambos os estados, enquanto que P. Penicillus apenas no Rio de Janeiro; P. hispidus ocorre em São Paulo, sendo a espécie do gênero com a distribuição mais ampla, sendo encontrada desde Minas Gerais até Santa Catarina

  • A new species of Pacholenus Schoenherr from southeastern Brazil (Coleoptera, Curculionidae, Molytinae), and new occurrences of species of the genus
    Papéis Avulsos de Zoologia, 2008
    Co-Authors: Sergio Antonio Vanin
    Abstract:

    A new species of Pacholenus Schoenherr from southeastern Brazil (Coleoptera, Curculionidae, Molytinae), and new occurrences of species of the genus. Pacholenus monteiroi sp. nov. (type-locality Brazil, Rio de Janeiro state, Carapebus, Parque Nacional da Restinga de Jurubatiba) is described and illustrated. The weevil develops as a stem gall-former in Calyptranthes brasiliensis Spreng (Myrtaceae). The new species is easily distinguished from the other five known of the genus by the presence of a prominent supra-ocular ridge. An updated key for identification for all species of Pacholenus is provided. Three species of Pacholenus are presently recorded for the states of Rio de Janeiro and Sao Paulo; P. pelliceus and P. monteiroi occur in both states, while P. Penicillus is only known from Rio de Janeiro; P. hispidus occurs in Sao Paulo, being the most widespread species of the genus, ranging from Minas Gerais south to Santa Catarina.

Stefan Mayer - One of the best experts on this subject based on the ideXlab platform.

  • particle capture in the crown of the ciliary suspension feeding polychaete sabella Penicillus videotape recordings and interpretations
    Marine Biology, 1994
    Co-Authors: Stefan Mayer
    Abstract:

    An experimental setup was designed for in situ videotape recording of the particle capture process in the crown of the polychaete Sabella Penicillus. Intact individuals of S. Penicillus (collected in the Gullmornfjord, Sweden in 1992) were exposed to either 6 μm Latex spheres or Rhodomonas sp. flagellate cells (6 μm). The capture of the added particles was recorded on video. From frameby-frame analyses particle velocities were estimated and the shape of the three-dimensional particle paths was inferred. The mean velocity of particles approaching the crown was estimated to be ca. 1 mm s-1, increasing to ca. 1.7 mm s-1 in the interpinnule channel. At the moment of capture the particles were seen to follow a curved, near circular path close to the tips of the latero-frontal cilia. The transport velocities on the frontal side of the pinnules and filaments were estimated to be up to 0.15 and 0.5 mm s-1, respectively. Counting captured particles relative to particles arriving within the area of the pinnules gave a rough, direct estimate of nearly 100% retention rate when the polychaete was feeding undisturbed. Together with results from clearance measurements in the literature this implies that the worm is able to capture particles down to 3 μm entering the interpinnule channel almost 100% effectively. In view of the 80-μm wide interpinnule channel and 40-μm spacing between the tips of the latero-frontal cilia on both sides of the channel, this result cannot be explained by mechanisms based solely on direct mechanical contact between cilia and particles but must involve fluid mechanical mechanisms. The present work is the experimental basis for ongoing numerical simulations of the particle motion in the interpinnule channel.

Masahisa Wada - One of the best experts on this subject based on the ideXlab platform.

  • crystal transition between hydrate and anhydrous 1 3 β d xylan from Penicillus dumetosus
    Carbohydrate Polymers, 2013
    Co-Authors: Kayoko Kobayashi, Satoshi Kimura, Laurent Heux, Masahisa Wada
    Abstract:

    The crystal structures of hydrated and anhydrous (1→3)-β-d-xylan and the crystal transition between them were investigated. Highly crystalline samples of (1→3)-β-d-xylan were prepared from a siphoneous green alga, Penicillus dumetosus. The crystal structure was analyzed using synchrotron X-ray diffraction and solid-state (13)C NMR spectroscopy. The hydrated form was converted to the anhydrous form with contraction in both the a-axis and c-axis directions, and the crystallinity decreased considerably at the same time. The crystal transition between hydrated and anhydrous (1→3)-β-d-xylan was monitored using synchrotron X-ray diffraction under controlled relative humidity. The transition took place at certain transition points, and was accompanied by a large hysteresis. From the difference in the weight and unit-cell volume at the transition points, the number of water molecules in the hydrated form was estimated as one per xylose residue.

Agostinho Antunes - One of the best experts on this subject based on the ideXlab platform.

  • Evidence of unique and generalist microbes in distantly related sympatric intertidal marine sponges (Porifera: Demospongiae). PloS one. 2013; 8(11): e80653. doi: 10.1371/journal.pone.0080653 PMID: 24265835
    2016
    Co-Authors: Anoop Alex, Vitor Silva, Vitor Vasconcelos, Agostinho Antunes
    Abstract:

    The diversity and specificity of microbial communities in marine environments is a key aspect of the ecology and evolution of both the eukaryotic hosts and their associated prokaryotes. Marine sponges harbor phylogenetically diverse and complex microbial lineages. Here, we investigated the sponge bacterial community and distribution patterns of microbes in three sympatric intertidal marine demosponges, Hymeniacidon perlevis, Ophlitaspongia papilla and Polymastia Penicillus, from the Atlantic coast of Portugal using classical isolation techniques and 16S rRNA gene clone libraries. Microbial composition assessment, with nearly full-length 16S rRNA gene sequences (ca. 1400 bp) from the isolates (n = 31) and partial sequences (ca. 280 bp) from clone libraries (n = 349), revealed diverse bacterial communities and other sponge-associated microbes. The majority of the bacterial isolates were members of the order Vibrionales and other symbiotic bacteria like Pseudovibrio ascidiaceiocola, Roseobacter sp., Hahellaceae sp. and Cobetia sp. Extended analyses using ecological metrics comprising 142 OTUs supported the clear differentiation of bacterial community profiles among the sponge hosts and their ambient seawater. Phylogenetic analyses were insightful in defining clades representing shared bacterial communities, particularly between H. perlevis and the geographically distantly-related H. heliophila, but also among other sponges. Furthermore, we also observed three distinct and unique bacterial groups, Betaproteobactria (,81%), Spirochaetes (,7%) and Chloroflexi (,3%), which are strictly maintained in low-microbial-abundance host species O. papilla and P. Penicillus. Our study reveale

  • Evidence of Unique and Generalist Microbes in Distantly Related Sympatric Intertidal Marine Sponges (Porifera: Demospongiae)
    2013
    Co-Authors: Anoop Alex, Vitor Silva, Vitor Vasconcelos, Agostinho Antunes
    Abstract:

    The diversity and specificity of microbial communities in marine environments is a key aspect of the ecology and evolution of both the eukaryotic hosts and their associated prokaryotes. Marine sponges harbor phylogenetically diverse and complex microbial lineages. Here, we investigated the sponge bacterial community and distribution patterns of microbes in three sympatric intertidal marine demosponges, Hymeniacidon perlevis, Ophlitaspongia papilla and Polymastia Penicillus, from the Atlantic coast of Portugal using classical isolation techniques and 16S rRNA gene clone libraries. Microbial composition assessment, with nearly full-length 16S rRNA gene sequences (ca. 1400 bp) from the isolates (n = 31) and partial sequences (ca. 280 bp) from clone libraries (n = 349), revealed diverse bacterial communities and other sponge-associated microbes. The majority of the bacterial isolates were members of the order Vibrionales and other symbiotic bacteria like Pseudovibrio ascidiaceiocola, Roseobacter sp., Hahellaceae sp. and Cobetia sp. Extended analyses using ecological metrics comprising 142 OTUs supported the clear differentiation of bacterial community profiles among the sponge hosts and their ambient seawater. Phylogenetic analyses were insightful in defining clades representing shared bacterial communities, particularly between H. perlevis and the geographically distantly-related H. heliophila, but also among other sponges. Furthermore, we also observed three distinct and unique bacterial groups, Betaproteobactria (∼81%), Spirochaetes (∼7%) and Chloroflexi (∼3%), which are strictly maintained in low-microbial-abundance host species O. papilla and P. Penicillus. Our study revealed the largely generalist nature of microbial associations among these co-occurring intertidal marine sponges.