title: New insights into the molecular phylogeny of Balantidium (Ciliophora, Vetibuliferida) based on the analysis of new sequences of species from fish hosts.
abstract: We obtained sequences of the small subunit ribosomal RNA (rRNA) for two new isolates of Balantidium from fishes, Balantidium polyvacuolum and Balantidium ctenopharingodoni. This is the first introduction of molecular data of Balantidium species from fish hosts in the phylogenetic analyses of the ciliate subclass Trichostomatia. Despite the fact that these species share morphological characteristics common to other species of Balantidium, the phylogenetic analysis of their sequences has shown that they are to be placed in a different branch closely related to the so-called Australian clade. Thus, our results indicate that the genus Balantidium is polyphyletic and possibly should be represented by two different genera; however, the analysis of more species from other poikilothermic hosts (amphibians, reptiles) should be made before a revised taxonomical proposal could be made.
authors.affiliation: Hubei Key Laboratory of Animal Nutrition and Feed Science, Wuhan Polytechnic University, Wuhan, 430023, China.
authors.forename: Ming
authors.initials: M
authors.lastname: Li
authors.forename: Francisco
authors.initials: F
authors.lastname: Ponce-Gordo
authors.forename: J Norman
authors.initials: JN
authors.lastname: Grim
authors.forename: Chong
authors.initials: C
authors.lastname: Wang
authors.forename: Frank
authors.initials: F
authors.lastname: Nilsen
mesh_terms: D000818:Animals; D001447:Balantidiasis / Q000469:parasitology / Q000662:veterinary*; D001448:Balantidium / Q000145:classification* / Q000235:genetics / Q000302:isolation & purification; D001483:Base Sequence; D016054:DNA, Protozoan / Q000737:chemistry / Q000235:genetics; D004275:DNA, Ribosomal / Q000737:chemistry / Q000235:genetics; D005393:Fish Diseases / Q000469:parasitology*; D005399:Fishes; D008969:Molecular Sequence Data; D010802:Phylogeny; D054679:Ribosome Subunits, Small / Q000235:genetics; D017422:Sequence Analysis, DNA / Q000662:veterinary
chemical_list: D016054:DNA, Protozoan; D004275:DNA, Ribosomal