ABSTRACT
Pungitius is a highly diversified genus of sticklebacks (Gasterosteidae) occurring widely in northern parts of the Northern Hemisphere. Several ecologically and genetically divergent types that are largely isolated reproductively but occasionally hybridize in sympatry have been discovered in Northeast Asia, although the taxonomy and evolutionary relationships among them remain unclear. We used amplified fragment length polymorphism (AFLP) and mitochondrial DNA (mtDNA) markers to infer phylogenies among individuals collected from sympatric and allopatric populations, including the type localities of the described species. Phylogenetic analyses based on 2683 polymorphic AFLP loci confirmed seven species, each of which (except for one entirely allopatric species P. platygaster) was clearly differentiated from one or two other sympatric species and constituted a highly supported monophyletic clade with conspecific allopatric populations. The phylogeny showed that two lineages arose early; one gave rise to two species (circumpolar species P. pungitius and Paratethys species P. platygaster) and the other to five species endemic to Northeast Asia (P. sinensis, P. tymensis, P. polyakovi, P. kaibarae, and P. bussei). The brackish-water, freshwater, and Omono types previously discovered in Japan were reidentified as P. pungitius, P. sinensis, and P. kaibarae, respectively. A marked incongruence was noted between the phylogenies of AFLP and mtDNA markers, suggesting the occasional occurrence of hybridization and mtDNA introgression among distinct species. Our results highlight that the marginal seas of Northeast Asia played a key role as barriers to or facilitators of gene flow in the evolution of species diversity of Pungitius concentrated in this region.
Subject(s)
Amplified Fragment Length Polymorphism Analysis/methods , DNA, Mitochondrial/genetics , Genetic Variation , Phylogeny , Smegmamorpha/genetics , Animals , Calibration , Cytochromes b/genetics , Asia, Eastern , Genetic Markers , Geography , Species Specificity , Time FactorsABSTRACT
We sequenced two complete mitochondrial genomes of the white-spotted char Salvelinus leucomaenis from two wild populations. The complete genome is 16,655 bp in size and its gene content, arrangement, codon usage and base composition are identical with those observed in salmonids. The detailed comparison with other complete mitochondrial genomes of Salvelinus revealed signs of recombination in one of them.
Subject(s)
Genome, Mitochondrial/genetics , Salmonidae/genetics , Sequence Analysis, DNA , Animals , Genes, rRNA , Molecular Sequence Annotation , Molecular Sequence Data , Open Reading Frames/genetics , Phylogeny , RNA, Transfer/geneticsABSTRACT
The complete mitochondrial genome sequence of Mesocottus haitej has been obtained by the next generation sequencing, which contained 22 tRNA genes, 13 protein-coding genes, 2 rRNA genes and non-coding control region with the total length of 16,527 bp. The gene content, arrangement, codon usage and base composition of M. haitej mitogenome have no unusual features that distinguish it from most other teleost fishes. According to the result of a pilot phylogenetic analysis, the freshwater Mesocottus is a sister lineage to the Cottus clade. The new mitogenomic data could provide useful information for the further studies on molecular systematics and conservation genetics of cottids.
Subject(s)
Genome, Mitochondrial , Mitochondria/genetics , Perciformes/genetics , Animals , Base Composition , Gene Order , Molecular Sequence Data , Phylogeny , RNA, Ribosomal/genetics , RNA, Transfer/genetics , Sequence Analysis, DNAABSTRACT
The complete mitochondrial genome sequence of Parahucho perryi has been obtained by the next generation sequencing, which contained 22 tRNA genes, 13 protein-coding genes, 2 rRNA genes and non-coding control region with the total length of 16,651 bp. The gene content, arrangement, codon usage and base composition of P. perryi mitogenome are identical to those observed in salmonids and most other teleost fishes. The sequence data could provide useful information for the studies on molecular systematics and conservation genetics.
Subject(s)
Endangered Species , Genome, Mitochondrial , Salmonidae/genetics , Animals , Codon , Molecular Sequence Data , Proteins/genetics , RNA, Ribosomal/genetics , RNA, Transfer/geneticsABSTRACT
Analyses of allozyme (18 loci) and partial mitochondrial DNA (mtDNA) sequences (1295 bp, 16S rRNA) support the classification of phoxinin minnows from the northern Far East into 2 genera of 8 species: Phoxinus phoxinus, Rhynchocypris oxycephalus, R. perenurus, R. czekanowskii, R. kumgangensis, R. semotilus, R. lagowskii and R. sp. (bergi ?). Although R. lagowskii from Japan and the Amur basin and R. sp. from Vladivostok region to Korea have been classified into a single species by many authors as R. lagowskii, they form separate clusters in both analyses, suggesting different specific status. Some R. oxycephalus and R. perenurus had the mtDNA haplotypes of R. lagowskii and R. czekanowskii, respectively, which probably indicates that local introgression of mtDNA occurred through inter-specific hybridization. Rhynchocypris forms a monophyletic cluster with dace genera Tribolodon and Pseudaspius, not with Phoxinus. Eurasian and American Phoxinus are suggested to be paraphyletic.
