North 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 PDFThe extent and nature of genetic differentiation in Semotilus atromaculatus, one of the most abundant and widespread leuciscids in North America, were evaluated based on mitochondrial (mt) and nuclear DNA sequence variation. Phylogenetic relationships were first inferred based on a fragment of the cytochrome b (cytb) region and the nuclear intron s7 gene for S. atromaculatus and all other congeners as well as representative species from all other genera in the creek chub-plagopterin clade.
View Article and Find Full Text PDFThe phylogenetic relationships and classification of the freshwater fish order Cypriniformes, like many other species-rich groups of vertebrates, has evolved over time with some consistency and inconsistencies of relationships across various studies. Within Cypriniformes, the Holarctic family Leuciscidae is one of the most widely distributed and highly diverse monophyletic groups of cyprinoids. Despite several studies conducted on this group, alternative hypotheses exist as to the composition and relationships within Leuciscidae.
View Article and Find Full Text PDFThis study represents a phylogenetic analysis of Pimephales notatus, a widely distributed North American cyprinid fish species, using one mitochondrial (cytb) and two nuclear (S7 and Rag1) genes. Despite the broad geographic distribution of this species that includes independent basins, results suggest a largely drainage-independent genetic structure. Results reveal a well-supported lineage in the Ozark Highlands, which is highly divergent from the remaining populations and may represent a long-term isolated lineage that should be considered as a separate conservation and management unit.
View Article and Find Full Text PDFSpecies of Gila comprise a heterogeneous and widespread group of freshwater fishes inhabiting drainage systems of western North America. The classification of species of Gila and relatives has been complicated and sometimes compromised by differences in body shapes, sizes, habitats, variable taxonomic placement by early taxonomists, and instances of hypothesized hybridization. While most attention on Gila has focused on hybridization in USA, little is actually know about their intra and intergeneric relationships.
View Article and Find Full Text PDFAccurate delimitation of species is a critical first step in protecting biodiversity. Detection of distinct species is especially important for groups of organisms that inhabit sensitive environments subject to recent degradation, such as creeks, springs, and rivers in arid or semi-desert regions. The genus Dionda currently includes six recognized and described species of minnows that live in clear springs and spring-fed creeks of Texas, New Mexico (USA), and northern Mexico, but the boundaries, delimitation, and characterization of species in this genus have not been examined rigorously.
View Article and Find Full Text PDFMembers of the genus Cyprinella are abundant and broadly distributed cyprinids in central and eastern rivers of North America. Currently, 30 species are placed in this genus, including seven species restricted to Mexico and three barbeled species formerly placed in different genera (Hybopsis, Erimonax). Phylogenetic analyses were performed for all recognized species of Cyprinella plus species from 14 related genera using complete nucleotide sequences of one mitochondrial (cytochrome b) and one nuclear (Rag1) gene.
View Article and Find Full Text PDFMost of the recognized species of the genus Dionda inhabit drainages of the Gulf of Mexico from central Mexico to central Texas, USA, and have been considered a monophyletic group based on morphological, osteological, and allozyme investigations. Phylogenetic relationships of 15 species of Dionda and 34 species from closely related genera were inferred from one mitochondrial (cytb) and three nuclear gene sequences (S7, Rhodopsin, Rag1) totaling 4487 nucleotides. Separate analyses of all four genes yield congruent phylogenies; however the 15 putative species of Dionda evaluated were never recovered as a monophyletic group when species from nine related genera were included in the analyses.
View Article and Find Full Text PDFMitochondrial 16S rRNA sequences from morphological validated grouper (Epinephelus aeneus, E. caninus, E. costae, and E.
View Article and Find Full Text PDF