title: Molecular phylogeny of three oxymonad genera: Pyrsonympha, Dinenympha and Oxymonas.
abstract: Oxymonads are a morphologically well-characterized and highly diverse lineage of protists. They are, however, under sampled at a molecular level. It has recently been demonstrated that a genus of oxymonads, Pyrsonympha, is phylogenetically related to the excavate taxon Trimastix. Here, we addressed issues of internal oxymonad evolution. Pyrsonympha and Dinenympha are shown, by fluorescent in situ hybridization and phylogenetic evidence, to be separate genera and not morphotypes of the same organism. We demonstrated that three genera of oxymonads, Dinenympha, Pyrsonympha, and Oxymonas are each monophyletic and together form a clade which excludes other known eukaryotes. We have presented a taxonomic scheme of oxymonads taking into account their sisterhood with Trimastix and speculated on morphological evolution of oxymonads, particularly of their attachment apparatuses. Our biogeographical analysis with Japanese and Canadian Pyrsonympha and Dinenympha suggests that these genera diverged before the separation of termites that inhabit Eastern Asia and Western North America.
authors.affiliation: Bioscience Technology Center, RIKEN institute, 2-1, Hirosawa, Wako, Saitama 351-0198, Japan. smoriya@postman.riken.go.jp
authors.forename: Shigeharu
authors.initials: S
authors.lastname: Moriya
authors.forename: Joel B
authors.initials: JB
authors.lastname: Dacks
authors.forename: Aika
authors.initials: A
authors.lastname: Takagi
authors.forename: Satoko
authors.initials: S
authors.lastname: Noda
authors.forename: Moriya
authors.initials: M
authors.lastname: Ohkuma
authors.forename: W Ford
authors.initials: WF
authors.lastname: Doolittle
authors.forename: Toshiaki
authors.initials: T
authors.lastname: Kudo
mesh_terms: D000818:Animals; D004275:DNA, Ribosomal / Q000032:analysis; D005057:Eukaryotic Cells / Q000145:classification*; D019143:Evolution, Molecular; D017403:In Situ Hybridization; D020049:Isoptera / Q000469:parasitology; D010802:Phylogeny; D017422:Sequence Analysis, DNA
chemical_list: D004275:DNA, Ribosomal