Molecular phylogeny of the Acanthocephala (class Palaeacanthocephala) with a paraphyletic assemblage of the orders Polymorphida and Echinorhynchida

• Published in: PloS one 2011-12, Vol.6 (12), p.e28285-e28285
• Main Authors: Verweyen, Lisa, Klimpel, Sven, Palm, Harry W
• Format: Article
• Language: English
• Subjects: Acanthocephala; Acanthocephala - genetics; Acanthocephala - physiology; Analysis; Animals; Archiacanthocephala; Bayes Theorem; Bayesian analysis; Biodiversity; Bioinformatics; Biology; Chaetognatha; Cycliophora; Datasets; Deoxyribonucleic acid; DNA; DNA, Helminth - genetics; Echinorhynchida; Ecological monitoring; Ecology; Ecosystem; Electrophoresis - methods; Eoacanthocephala; Evolution; Female; Filisoma rizalinum; Genera; Gnathostomulida; Life cycles; Likelihood Functions; Male; Marine ecosystems; Microscopy, Electron, Scanning - methods; Models, Genetic; Morphology; New records; Nucleic Acids - genetics; Palaeacanthocephala; Parasitology; Phylogenetics; Phylogeny; Polyacanthocephala; Polymorphida; Reproducibility of Results; Reptiles & amphibians; Restriction Mapping - methods; Rhadinorhynchus lintoni; RNA, Ribosomal, 18S - metabolism; Rotifera; Sequence Analysis, DNA; Species; Species Specificity; Statistical inference; Stochastic models; Studies; Taxa; Taxonomy
• ISSN: 1932-6203; 1932-6203
• DOI: 10.1371/journal.pone.0028285

Acanthocephalans are attractive candidates as model organisms for studying the ecology and co-evolutionary history of parasitic life cycles in the marine ecosystem. Adding to earlier molecular analyses of this taxon, a total of 36 acanthocephalans belonging to the classes Archiacanthocephala (3 species), Eoacanthocephala (3 species), Palaeacanthocephala (29 species), Polyacanthocephala (1 species) and Rotifera as outgroup (3 species) were analyzed by using Bayesian Inference and Maximum Likelihood analyses of nuclear 18S rDNA sequence. This data set included three re-collected and six newly collected taxa, Bolbosoma vasculosum from Lepturacanthus savala, Filisoma rizalinum from Scatophagus argus, Rhadinorhynchus pristis from Gempylus serpens, R. lintoni from Selar crumenophthalmus, Serrasentis sagittifer from Johnius coitor, and Southwellina hispida from Epinephelus coioides, representing 5 new host and 3 new locality records. The resulting trees suggest a paraphyletic arrangement of the Echinorhynchida and Polymorphida inside the Palaeacanthocephala. This questions the placement of the genera Serrasentis and Gorgorhynchoides within the Echinorhynchida and not the Polymorphida, necessitating further insights into the systematic position of these taxa based on morphology.