Topic
Stenodus
About: Stenodus is a research topic. Over the lifetime, 19 publications have been published within this topic receiving 582 citations.
Papers
TL;DR: It is found that some groups in Salmonidae are older than previously thought and that the mitochondrial rate of molecular divergence varies markedly among genes and clades, and some species require taxonomic revision, including two monotypic genera, Stenodus and Salvethymus.
Abstract: Considerable research efforts have focused on elucidating the systematic relationships among salmonid fishes; an understanding of these patterns of relatedness will inform conservation- and fisheries-related issues, as well as provide a framework for investigating evolutionary mechanisms in the group However, uncertainties persist in current Salmonidae phylogenies due to biological and methodological factors, and a comprehensive phylogeny including most representatives of the family could provide insight into the causes of these difficulties Here we increase taxon sampling by including nearly all described salmonid species (n = 63) to present a time-calibrated and more complete portrait of Salmonidae using a combination of molecular markers and analytical techniques This strategy improved resolution by increasing the signal-to-noise ratio and helped discriminate methodological and systematic errors from sources of difficulty associated with biological processes Our results highlight novel aspects of salmonid evolution First, we call into question the widely-accepted evolutionary relationships among sub-families and suggest that Thymallinae, rather than Coregoninae, is the sister group to the remainder of Salmonidae Second, we find that some groups in Salmonidae are older than previously thought and that the mitochondrial rate of molecular divergence varies markedly among genes and clades We estimate the age of the family to be 591 MY (CI: 632-581 MY) old, which likely corresponds to the timing of whole genome duplication in salmonids The average, albeit highly variable, mitochondrial rate of molecular divergence was estimated as ∼031%/MY (CI: 027–036%/MY) Finally, we suggest that some species require taxonomic revision, including two monotypic genera, Stenodus and Salvethymus In addition, we resolve some relationships that have been notoriously difficult to discern and present a clearer picture of the evolution of the group Our findings represent an important contribution to the systematics of Salmonidae, and provide a useful tool for addressing questions related to fundamental and applied evolutionary issues
247 citations
TL;DR: The widespread genetic groupings obtained for ciscoes indicate that they do not constitute a single closely related group within the genus Coregonus, and European and lake whitefish may be conspecific.
Abstract: The genetic relationships among New and Old World coregonid fishes were studied by electrophoresis. The genetic composition of 60 populations, representing perhaps nine commonly recognized species of Coregonus and Stenodus from Europe and North America was determined for 37 genetic loci. Six distinct genetic groups were evident. The first contained only populations of the inconnu, Stenodus leucichthys (Guldenstadt). The Nei genetic distance between Stenodus and Coregonus was 0.305, a relatively small value as compared to other salmonid inter-generic comparisons. The second genetic grouping contained the Arctic cisco, C. autumnalis (Pallas), the N. American lake cisco, C. artedii Lesueur, and the Irish pollan, C. autumnalis pollan Thompson. These three taxa appear to be conspecific on the basis of genetic distances. The third genetic grouping contained the European whitefish, C. lavaretus (L.), and the N. American lake whitefish, C. clupeaformis (Mitchill). European and lake whitefish may be conspecific. Lake whitefish from northwestern N. America were more closely related to European whitefish (genetic distance 0.038) than to lake whitefish from central N. America (genetic distance 0.098). The fourth group contained the broad whitefish, C. nasus (Pallas), which is perhaps more closely related to the European/lake whitefish groups than other coregonids. The fifth genetic grouping contained only the Asian endemic, C. peled (Gmelin), and the sixth contained the least cisco, C. sardinella Valenciennes, and vendace, C. albula (L.), which also appear to be conspecific. The widespread genetic groupings obtained for ciscoes indicate that they do not constitute a single closely related group within the genus Coregonus.
73 citations
TL;DR: A four-year study of the fish of Great Slave Lake was initiated one year before the lake was opened for commercial fishing, information has been obtained about the composition, distribution and general ecology of the major species.
Abstract: A four-year study of the fish of Great Slave Lake was initiated one year before the lake was opened for commercial fishing. Information has been obtained about the composition, distribution and general ecology of the major species. Twenty-one species are listed and the ciscoes, probably of three species, await identification. Lake trout, common whitefish and ciscoes dominate the population and the former two species support an extensive gill-net fishery. The inconnu Stenodus, and the deepwater sculpin, Triglopsis, are of special zoogeographic interest.Sampling was mainly with standardized 300-yard gangs of gill net. In these, some 12,000 fish weighing about 20,000 pounds were taken. Some data were obtained on the selective effect of mesh size. Young and small fish were collected by seining.Great Slave Lake's area of 10,500 square miles includes a large open portion and two great arms, one to the north, the other extending eastward. Part of the north arm is shallow and its fish population is much like that...
58 citations
TL;DR: Phylogenetic analyses based on morphometrics, data on protein electrophoresis, and mitochondrial DNA have given conflicting phylogenetic hypotheses for the subfamily Coregoninae, and a nuclear gene, the first internal transcribed spacer (ITS1) of the ribosomal DNA (rDNA) was used to resolve conflicts.
Abstract: Phylogenetic analyses based on morphometrics, data on protein electrophoresis, and mitochondrial DNA have given conflicting phylogenetic hypotheses for the subfamily Coregoninae (Prosopium, Coregonus, and Stenodus). To resolve these conflicts, phylogenetic analysis of 13 taxa of Coregoninae was done using a nuclear gene, the first internal transcribed spacer (ITS1) of the ribosomal DNA (rDNA). ITS1 sequences of all North American ciscoes were identical. In agreement with analyses based on other molecular data, the genus Stenodus was included in Coregonus, and there was no support for the monophyly of the ciscoes. The analysis based on rDNA also placed C. peled as the sister species to C. lavaretus, but this may represent a case of hybridization and introgression. A length polymorphism involving a repeating unit of 65-67 base pairs was found in the ITS1. All ciscoes except C. peled had one copy of the repeat. Coregonus peled, C. lavaretus, and Eurasian and Beringian C. clupeaformis had two copies of the re...
40 citations
TL;DR: This DNA barcode‐based assay promises to aid fishery managers and researchers by providing a cost‐effective alternative to large‐scale sequence analysis for identification of North American coregonine fishes.
Abstract: Coregonine fishes have a circumpolar distribution in the Arctic and sub-Arctic Northern Hemisphere. This subfamily of Salmonidae consists of three genera: Prosopium, Stenodus and Coregonus, including over 30 species. Many species overlap spatially and are difficult to distinguish based on morphological characteristics, especially as larvae or juveniles. Here we present a method for rapid and cost-effective species identification for representatives of the three genera based on sequence variation at the mitochondrial cytochrome c oxidase subunit I gene (COI). We examined eight species common to North America with distributional overlap in Alaska. Mean pairwise sequence divergence for all eight species was 7.04% and ranged from 0.46% to 14.23%. This sequence variation was used to develop a genetic assay based on restriction fragment length polymorphism. In a blind test, this assay provided correct species assignment for 48 of 49 individuals representing all eight species. The single incorrect assignment may reflect hybridization between two closely related species. This DNA barcode-based assay promises to aid fishery managers and researchers by providing a cost-effective alternative to large-scale sequence analysis for identification of North American coregonine fishes.
24 citations
Related Topics (5)
Performance Metrics
| Year | Papers |
|---|---|
| 2014 | 1 |
| 2012 | 2 |
| 2010 | 1 |
| 2008 | 1 |
| 1999 | 1 |
| 1998 | 1 |