title: Mitochondrial phylogeny of trematomid fishes (Nototheniidae, Perciformes) and the evolution of Antarctic fish.
abstract: The subfamily of fishes Trematominae is endemic to the subzero waters of antarctica and is part of the longer notothenioid radiation. Partial mitochondrial sequences from the 12S and 16S ribosomal RNA (rRNA) genes and a phylogeny for 10 trematomid species are presented. As has been previously suggested, two taxa, Trematomus scotti and T. newnesi, do not appear to be part of the main trematomid radiation. The genus Pagothenia is nested within the genus Trematomus and has evolved a unique cyropelagic existence, an association with pack ice. Using a mitochondrial rRNA molecular clock rate of 0.14% transversion changes per million years, the average age of the trematomids is estimated at 3.4 million years (MY). If the age of the trematomids is approximately 3.4 MY, this group could have speciated during the period of deglaciation in Antarctica 2.5-4.8 million years ago. This era was marked by significant changes on the Antarctic shores, such as the opening of fjords, which might have provided a stimulus for specification.
authors.affiliation: School of Biological Sciences, University of Auckland, New Zealand.
authors.forename: P A
authors.initials: PA
authors.lastname: Ritchie
authors.forename: L
authors.initials: L
authors.lastname: Bargelloni
authors.forename: A
authors.initials: A
authors.lastname: Meyer
authors.forename: J A
authors.initials: JA
authors.lastname: Taylor
authors.forename: J A
authors.initials: JA
authors.lastname: Macdonald
authors.forename: D M
authors.initials: DM
authors.lastname: Lambert
mesh_terms: D000818:Animals; D000864:Antarctic Regions; D001483:Base Sequence; D005075:Biological Evolution; D017931:DNA Primers; D004272:DNA, Mitochondrial / Q000235:genetics*; D004275:DNA, Ribosomal / Q000235:genetics; D014644:Genetic Variation; D008930:Mitochondria, Liver / Q000378:metabolism; D008931:Mitochondria, Muscle / Q000378:metabolism; D008969:Molecular Sequence Data; D018482:Muscle, Skeletal / Q000378:metabolism; D010473:Perciformes / Q000145:classification / Q000235:genetics*; D010802:Phylogeny; D016133:Polymerase Chain Reaction; D012335:RNA, Ribosomal / Q000235:genetics*; D012336:RNA, Ribosomal, 16S / Q000235:genetics*; D012044:Regression Analysis; D012689:Sequence Homology, Nucleic Acid
chemical_list: D017931:DNA Primers; D004272:DNA, Mitochondrial; D004275:DNA, Ribosomal; D012335:RNA, Ribosomal; D012336:RNA, Ribosomal, 16S; C075526:RNA, ribosomal, 12S