title: A molecular reassessment of the Leptomyxid amoebae.
abstract: Leptomyxid amoebae encompass a diverse assemblage of amoeboid protists that have been implicated as encephalitis-causing agents. This characteristic is attributed to recent studies identifying new members of the Leptomyxidae, in particular, Balamuthia mandrillaris, that cause the disease. Their morphologies range from limax to plasmodial, as well as reticulated and polyaxial. Although systematic studies have identified B. mandrillaris as a new member of the Leptomyxidae, its precise placement within the leptomyxids is uncertain. To further assess the taxonomic placement of Balamuthia among the leptomyxid amoebae and to determine whether the members of the Leptomyxida form a monophyletic assemblage, we have sequenced 16S-like rRNA genes from representatives of three leptomyxid families. Our phylogenetic analyses revealed that current members of the order Leptomyxida do not constitute a monophyletic assemblage. Our analyses clearly show that Gephyramoeba, as well as Balamuthia do not belong in the order Leptomyxida. We highlight where molecular data give differing insights than taxonomic schemes based on traditional characters.
authors.affiliation: The Josephine Bay Paul Center for Comparative Molecular Biology and Evolution, Marine Biological Laboratory, Woods Hole, MA 02543, USA.
authors.forename: L A
authors.initials: LA
authors.lastname: Amaral Zettler
authors.forename: T A
authors.initials: TA
authors.lastname: Nerad
authors.forename: C J
authors.initials: CJ
authors.lastname: O'Kelly
authors.forename: M T
authors.initials: MT
authors.lastname: Peglar
authors.forename: P M
authors.initials: PM
authors.lastname: Gillevet
authors.forename: J D
authors.initials: JD
authors.lastname: Silberman
authors.forename: M L
authors.initials: ML
authors.lastname: Sogin
mesh_terms: D000656:Amoeba / Q000235:genetics*; D000818:Animals; D016013:Likelihood Functions; D008969:Molecular Sequence Data; D010802:Phylogeny; D012336:RNA, Ribosomal, 16S; D017422:Sequence Analysis, DNA
chemical_list: D012336:RNA, Ribosomal, 16S