title: Molecular phylogeny of parabasalids inferred from small subunit rRNA sequences, with emphasis on the Hypermastigea.
abstract: Small subunit rRNA gene sequences were identified without cultivation from parabasalid symbionts of termites belonging to the hypermastigid orders Trichonymphida (the genera Hoplonympha, Staurojoenina, Teranympha, and Eucomonympha) and Spirotrichonymphida (Spirotrichonymphella), and from four yet-unidentified parabasalid symbionts of the termite Incisitermes minor. All these new sequences were analyzed by Bayesian, likelihood, and parsimony methods in a broad phylogeny including all identified parabasalid sequences available in databases and some as yet unidentified sequences probably derived from hypermastigids. A salient point of our study focused on hypermastigids was the polyphyly of this class. We also noted a clear dichotomy between Trichonymphida and the other parabasalid taxa. However, this hypermastigid order was apparently polyphyletic, probably reflecting its morphological diversity. Among Trichonymphida, Teranympha (Teranymphidae) grouped together with the members of the family Eucomonymphidae, suggesting that its family status is ambiguous. The monophyletic lineage composed by Spirotrichonymphida exhibited a narrower branching pattern than Trichonymphida. The root of parabasalids was examined but could not be discerned accurately.
authors.affiliation: Environmental Molecular Biology Laboratory, RIKEN, Wako, Saitama 351-0198, Japan. mohkuma@riken.jp
authors.forename: Moriya
authors.initials: M
authors.lastname: Ohkuma
authors.forename: Toshiya
authors.initials: T
authors.lastname: Iida
authors.forename: Kuniyo
authors.initials: K
authors.lastname: Ohtoko
authors.forename: Hiroe
authors.initials: H
authors.lastname: Yuzawa
authors.forename: Satoko
authors.initials: S
authors.lastname: Noda
authors.forename: Eric
authors.initials: E
authors.lastname: Viscogliosi
authors.forename: Toshiaki
authors.initials: T
authors.lastname: Kudo
mesh_terms: D000818:Animals; D001483:Base Sequence; D001499:Bayes Theorem; D019295:Computational Biology; D017931:DNA Primers; D056890:Eukaryota / Q000145:classification / Q000166:cytology* / Q000235:genetics*; D020049:Isoptera / Q000469:parasitology*; D007564:Japan; D016013:Likelihood Functions; D008957:Models, Genetic; D008969:Molecular Sequence Data; D010802:Phylogeny; D012335:RNA, Ribosomal / Q000235:genetics; D017422:Sequence Analysis, DNA
chemical_list: D017931:DNA Primers; D012335:RNA, Ribosomal