title: Further consideration of the phylogeny of some "traditional" heterotrichs (Protista, Ciliophora) of uncertain affinities, based on new sequences of the small subunit rRNA gene.
abstract: The systematic relationships and taxonomic positions of the traditional heterotrich genera Condylostentor, Climacostomum, Fabrea, Folliculina, Peritromus, and Condylostoma, as well as the licnophorid genus Licnophora, were re-examined using new data from sequences of the gene coding for small subunit ribosomal RNA. Trees constructed using distance-matrix, Bayesian inference, and maximum-parsimony methods all showed the following relationships: (1) the "traditional" heterotrichs consist of several paraphyletic groups, including the current classes Heterotrichea, Armophorea and part of the Spirotrichea; (2) the class Heterotrichea was confirmed as a monophyletic assemblage based on our analyses of 31 taxa, and the genus Peritromus was demonstrated to be a peripheral group; (3) the genus Licnophora occupied an isolated branch on one side of the deepest divergence in the subphylum Intramacronucleata and was closely affiliated with spirotrichs, armophoreans, and clevelandellids; (4) Condylostentor, a recently defined genus with several truly unique morphological features, is more closely related to Condylostoma than to Stentor; (5) Folliculina, Eufolliculina, and Maristentor always clustered together with high bootstrap support; and (6) Climacostomum occupied a paraphyletic position distant from Fabrea, showing a close relationship with Condylostomatidae and Chattonidiidae despite of modest support.
authors.affiliation: Ocean University of China, Qingdao, China.
authors.forename: Miao
authors.initials: M
authors.lastname: Miao
authors.forename: Weibo
authors.initials: W
authors.lastname: Song
authors.forename: John C
authors.initials: JC
authors.lastname: Clamp
authors.forename: Khaled A S
authors.initials: KA
authors.lastname: Al-Rasheid
authors.forename: Abdulaziz A
authors.initials: AA
authors.lastname: Al-Khedhairy
authors.forename: Saud
authors.initials: S
authors.lastname: Al-Arifi
mesh_terms: D000818:Animals; D001483:Base Sequence; D016798:Ciliophora / Q000145:classification* / Q000235:genetics; D016054:DNA, Protozoan / Q000737:chemistry / Q000235:genetics; D004275:DNA, Ribosomal / Q000737:chemistry / Q000235:genetics; D020459:Genes, rRNA; D008958:Models, Molecular; D008969:Molecular Sequence Data; D009690:Nucleic Acid Conformation; D010802:Phylogeny; D016053:RNA, Protozoan / Q000235:genetics; D012337:RNA, Ribosomal, 18S / Q000235:genetics; D017422:Sequence Analysis, DNA
chemical_list: D016054:DNA, Protozoan; D004275:DNA, Ribosomal; D016053:RNA, Protozoan; D012337:RNA, Ribosomal, 18S