Angiostrongylus vasorumfrom South America and Europe represent distinct lineages

Abstract

SUMMARYAngiostrongylus vasorumis a nematode parasite of sylvan and domestic species of the family Canidae. It has a broad but patchy distribution worldwide, and there is evidence for geographical spread and increasing incidence of infection in recent years. While historicallyAngiostrongylus-like nematodes identified in dogs and foxes have been described asA. vasorumin Europe andAngiocaulus raillietiin South America, more recent taxonomic revision has amalgamated these into a single species,A. vasorum. Here we report, for the first time, the molecular characterization of isolates ofA. vasorumfrom Germany, Portugal, Denmark and the United Kingdom on the basis of the mitochondrial COI gene and the second ribosomal internal transcribed spacer. When compared with isolates from Brazil, sequence analysis revealed 2 distinct genotypes. Estimated rates of evolution based on COI sequences for both nematode and host are consistent with the hypothesis that the presence ofA. vasorumin South America is a result of an ancient evolutionary event.Angiostrongylus vasorumin South America potentially represents a separate species to that observed in Europe.