Jawless vertebrates once dominated Palaeozoic waters, but just two lineages have persisted to the present day: lampreys and hagfishes. Living lampreys are a relatively small clade, with just over 50 species described, but knowledge of their evolutionary relationships has always been based on either a few mitochondrial genes or a small number of taxa. Biogeographers have noted the disjunct antitropical distribution of living lamprey families.
View Article and Find Full Text PDFBiology (Basel)
December 2024
Fishes in the cypriniform family Catostomidae (suckers) are evolutionary tetraploids. The use of nuclear markers in the phylogenetic study of this important group has been greatly hindered by the challenge of identifying paralogous copies of genes. In the present study, we used two different methods to separate the gene copies of five single-copy nuclear genes (i.
View Article and Find Full Text PDFNorth American minnows of the Shiner Clade, within the family Leuciscidae, represent one of the most taxonomically complex clades of the order Cypriniformes due to the large number of taxa coupled with conserved morphologies. Species within this clade were moved between genera and subgenera until the community decided to lump many of the unclassified taxa with similar morphologies into one genus, , which has held up to 325 species. Despite phylogentic studies that began to re-elevate some genera merged into , such as , , , and , the large genus remained as a taxonomic repository for many shiners of uncertain placement.
View Article and Find Full Text PDFFive ecologically and phenotypically divergent ecomorphs of the genus Salmo are known from a landlocked alpine lake in the Caucasus, Lake Sevan. It is an example of sympatric diversification within a species-rich lineage with predominate mode of speciation being allopatric. The diversification of Sevan trouts was accompanied by spawning resource partitioning.
View Article and Find Full Text PDFDespite the rarity of polyploidy in animals, some groups with polyploid species exhibit complicated and interesting patterns of reticulate evolution. Here we focus on fishes in the subfamily Cyprininae, the largest polyploid group of vertebrates. The large number of polyploid taxa poses significant challenges for phylogenetic and evolutionary studies on this subfamily.
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