0000000000053927

AUTHOR

Peter D. Olson

0000-0002-4183-4533

showing 5 related works from this author

Molecules and morphology reveal cryptic variation among digeneans infecting sympatric mullets in the Mediterranean.

2009

SUMMARYWe applied a combined molecular and morphological approach to resolve the taxonomic status of Saccocoelium spp. parasitizing sympatric mullets (Mugilidae) in the Mediterranean. Eight morphotypes of Saccocoelium were distinguished by means of multivariate statistical analyses: 2 of Saccocoelium obesum ex Liza spp.; 4 of S. tensum ex Liza spp.; and 2 (S. cephali and Saccocoelium sp.) ex Mugil cephalus. Sequences of the 28S and ITS2 rRNA gene regions were obtained for a total of 21 isolates of these morphotypes. Combining sequence data analysis with a detailed morphological and multivariate morphometric study of the specimens allowed the demonstration of cryptic diversity thus rejecting…

SympatrySpecies complexMolecular Sequence DataZoologyTrematode InfectionsFish DiseasesSpecies SpecificityGenetic variationDNA Ribosomal SpacerRNA Ribosomal 28SMediterranean SeaAnimalsRibosomal DNAPhylogenyGenetic diversitybiologyMugilGenetic VariationSequence Analysis DNADNA Helminthbiology.organism_classificationSmegmamorphaGenetic divergenceInfectious DiseasesSympatric speciationAnimal Science and ZoologyParasitologyTrematodaSequence AlignmentParasitology
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Independent host switching events by digenean parasites of cetaceans inferred from ribosomal DNA

2015

Cetaceans harbour a unique fauna of digeneans whose origin and relationships have sparked considerable debate during recent decades. Disparity in the species reported indicates that they do not share close affinities, but their unusual morphology has made their taxonomic identities and phylogenetic positions uncertain. Here we use sequence data to investigate the phylogenetic relationships of the main species of flukes infecting cetaceans. We sequenced the 18S, 28S and internal transcribed spacer 2 rDNA of digenean species representing all known families reported from cetaceans: Braunina cordiformis (Brauninidae), Ogmogaster antarcticus (Notocotylidae), Pholeter gastrophilus (Heterophyidae)…

ParaphylyMolecular Sequence DataZoologyHeterophyidaeDNA RibosomalDigeneaDNA Ribosomal SpacerRNA Ribosomal 28SRNA Ribosomal 18SAnimalsCluster AnalysisCladePhylogenybiologyPhylogenetic treeBiodiversitySequence Analysis DNADNA Helminthbiology.organism_classificationOpisthorchiidaeInfectious DiseasesMolecular phylogeneticsParasitologyTaxonomy (biology)CetaceaTrematodaInternational Journal for Parasitology
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Insight into the role of cetaceans in the life cycle of the tetraphyllideans (Platyhelminthes: Cestoda)

2007

Abstract Four types of tetraphyllidean larvae infect cetaceans worldwide: two plerocercoids differing in size, ‘small’ (SP) and ‘large’ (LP), and two merocercoids referred to as Phyllobothrium delphini and Monorygma grimaldii . The latter merocercoid larvae parasitize marine mammals exclusively and exhibit a specialised cystic structure. Adult stages are unknown for any of the larvae and thus the role of cetaceans in the life cycle of these species has been a long-standing problem. The SP and LP forms are thought to be earlier stages of P. delphini and M. grimaldii that are presumed to infect large pelagic sharks that feed on cetaceans. A molecular analysis of the D2 variable region of the …

Life Cycle StagesLarvabiologyEcologyDolphinsCestodaZoologyCetaceaMarine invertebratesCestode Infectionsbiology.organism_classificationHost-Parasite InteractionsTetraphyllideaInfectious DiseasesGenusPlerocercoidAnimalsCestodaParasitologyMesenteriesInternational Journal for Parasitology
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Morphological and molecular characterization of tetraphyllidean merocercoids (Platyhelminthes: Cestoda) of striped dolphins (Stenella coeruleoalba) f…

2005

Two types of tetraphyllidean merocercoids, Phyllobothrium delphini and Monorygma grimaldii, are well known from most cetaceans world-wide. The role of cetaceans in the life-cycle of these merocercoids is unclear because their specific identity is as yet unknown. The problem is compounded by poor descriptions of both merocercoids. We used light and scanning electron microscopy, and histological techniques to provide a thorough description of merocercoids collected from 11 striped dolphins, Stenella coeruleoalba, from the Spanish Mediterranean. We also described, for the first time, specimens of P. delphini with immature proglottides. Our merocercoids were morphologically similar to those des…

MaleDolphinsCestodaCetaceaZoologyHelminth geneticsStenella coeruleoalbaPolymerase Chain ReactionPhylogeneticsbiology.animalMediterranean SeaParasite hostingAnimalsCladePhylogenybiologyBase SequenceAbdominal CavityDNA Helminthbiology.organism_classificationTetraphyllideaInfectious DiseasesRNA RibosomalSpainMicroscopy Electron ScanningCestodaAnimal Science and ZoologyParasitologyFemaleParasitology
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Interrelationships of the Haploporinae (Digenea: Haploporidae): A molecular test of the taxonomic framework based on morphology

2009

The taxonomic framework of the Haploporidae is evaluated and the relationships within the Haploporinae are assessed for the first time at the generic level using molecular data. Partial 28S and complete ITS2 rDNA sequences from representatives of six of the nine recognised genera within the Haploporinae were analysed together with published sequences representing members of two haploporid subfamilies and of the closely related family Atractotrematidae. Molecular analyses revealed: (i) a close relationship between the Atractotrematidae and the Haploporidae; (ii) strong support for the monophyly of the Haploporinae, Dicrogaster and Saccocoelium, and the position of Ragaia within the Haplopori…

biologyZoologySequence Analysis DNATrematode InfectionsDNA Helminthbiology.organism_classificationDNA RibosomalSmegmamorphaDigeneaCladisticsEvolution MolecularFish DiseasesMonophylyInfectious DiseasesSister groupGenusDNA Ribosomal SpacerRNA Ribosomal 28SMolecular phylogeneticsAnimalsParasitologyTaxonomy (biology)TrematodaPhylogenyHaploporusParasitology International
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