22 research outputs found

    The Centipede Genus Scolopendra in Mainland Southeast Asia: Molecular Phylogenetics, Geometric Morphometrics and External Morphology as Tools for Species Delimitation

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    Copyright: © 2015 The PLOS ONE Staff. This is an open access article distributed under the terms of the Creative Commons Attribution License [4.0], which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. The attached file S1 is the corrected, republished version of the article. The attached file S2 is the original, uncorrected version of the article

    An annotated type catalogue of seven genera of operculate land snails (Caenogastropoda, Cyclophoridae) in the Natural History Museum, London

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    The collection of the seven cyclophorid snail genera housed in the Natural History Museum, London (NHM), includes 95 available species-level names belonging to the genera Pterocyclos Benson, 1832, Cyclotus Swainson, 1840, Myxostoma Troschel, 1847, Rhiostoma Benson, 1860, Scabrina Blanford, 1863, Crossopoma Martens, 1891, and Pearsonia Kobelt, 1902. Lectotypes are here designated for twelve available species-level names to stabilise existing the nomenclature. A complete catalogue of these types, including colour photographs, is provided for the first time. After examining these type specimens, an unpublished manuscript name was found and is described herein as Pterocyclos anamullayensis Sutcharit & Panha, sp. n.This is an open access article distributed under the terms of the Creative Commons Attribution License (CC BY 4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. The attached file is the published version of the article.NHM Repositor

    Membrane electrode assembly degradation under idle conditions via unsymmetrical reactant relative humidity cycling

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    The objective of this study is to investigate membrane electrode assembly (MEA) failure modes under accelerated test conditions via reactant relative humidity (RH) cycling. In this study, the anode and cathode underwent RH cycling in an unsymmetrical manner and the cell was run at a minimal \u201cidle\u201d current during endurance testing. The cell performance was monitored periodically and the degradation curve showed a difference in the anode and cathode induced RH cycling modes. Anode RH cycling had a more pronounced effect on MEA degradation than cathode RH cycling. Electrochemical diagnostic testing methods such as AC impedance and H2 crossover measurements revealed the degradation phenomena in more detail. The fluoride release data of the anode RH cycling cell showed a sudden increase in fluoride rate within a short period of endurance testing. The infrared imaging results revealed thinning and hotspot pinholes in the membrane, and ionomer delamination from the PTFE reinforcement layer was identified by scanning electron microscopy. The anode RH cycling cell had a shorter lifespan than the cell with cathode RH cycling, highlighting the significance of anode humidification for MEA durability.Peer reviewed: YesNRC publication: Ye

    Notes on the sinistral helicoid snail Bertia cambojiensis (Reeve, 1860) from Vietnam (Eupulmonata, Dyakiidae)

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    Since the time of the original description there have been no precise locality records in Cambodia of Bertia cambojiensis (Reeve, 1860) and it was believed to be extinct. In 2012, a joint Natural History Museum survey with Vietnamese colleagues rediscovered living populations of this huge sinistral helicoid snail in a protected area of southern Vietnam. The genitalia and radula morphology are re-assessed and type specimens of all recognised congeners are figured herein. The unique morphological characters of this species are a small and simple penis, well-developed amatorial organ complex that incorporates four amatorial organ ducts, a short gametolytic organ complex and spiked papilla, and radula morphology with unicuspid teeth. The type locality of B. cambojiensis, which has been contentious, is determined here to be in the vicinity of ‘Brelum’, Vietnam, near the border with Cambodia. In addition, the nucleotide sequences of barcoding genes COI, 16SrRNA and 28S fragments were provided for further comparison.Copyright Chirasak Sutcharit et al. This is an open access article distributed under the terms of the Creative Commons Attribution License (CC BY 4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.NHM Repositor

    Fusiforma themisticola n. gen., n. sp., a New Genus and Species of Apostome Ciliate Infecting the Hyperiid Amphipod Themisto libellula in the Canadian Beaufort Sea (Arctic Ocean), and Establishment of the Pseudocolliniidae (Ciliophora, Apostomatia)

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    A novel parasitic ciliate Fusiforma themisticola n. gen., n. sp. was discovered infecting 4.4% of the hyperiid amphipod Themisto libellula. Ciliates were isolated from a formaldehyde-fixed whole amphipod and the DNA was extracted for amplification of the small subunit (SSU) rRNA gene. Sequence and phylogenetic analyses showed unambiguously that this ciliate is an apostome and about 2% divergent from the krill-infesting apostome species assigned to the genus Pseudocollinia. Protargol silver impregnation showed a highly unusual infraciliature for an apostome. There are typically 8 (6-9) bipolar somatic kineties covering the banana-shaped body. The anterior end of the oral cavity begins about 1/3 of the body length from the anterior end and is composed of an inpocketing that is lined on its anterior and left wall with an oral field of densely packed ciliated kinetosomes. Stomatogenesis begins with some dedifferentiation of the parental oral field and elongation of its paroral and oral kineties. A new oral field develops midventrally and the paroral and oral kineties break to form the oral apparatus of the opisthe, which completes development by additional kinetosomal proliferation and migration of the paroral. This morphology is novel among apostomes and justifies the establishment of a new genus and specie
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