It is commonly accepted that among recent fishes the lungfishes are the closest relatives of the tetrapods. According to this hypothesis, the tetrapods, lungfishes and coelacanths constitute a group of specialized fishes (Sarcopterygii) to the exclusion of other bony fishes. Here, we describe basal relationships among gnathostome (jawed) vertebrates as reconstructed by analysis of complete mitochondrial DNA sequences. The study includes all major extant groups of both tetrapods and fishes and uses agnathan (jawless) vertebrates as an outgroup to root the trees. The analyses split extant gnathostomes into two monophyletic groups: tetrapods and fishes (including cartilaginous fishes). Cladistia (bichirs, ropefish) is in a basal position on the piscine branch. Thus, contrary to the traditional view, the mitogenomic results suggest that among living gnathostomes a tetrapod is a tetrapod and a fish, a fish. Similarly, analyses of 18S and 28S rRNA genes (both nuclear) do not support the commonly accepted tree.
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http://dx.doi.org/10.1016/j.gene.2004.02.014 | DOI Listing |
Dev Growth Differ
January 2025
Graduate School of Science and Engineering, Saitama University, Saitama, Japan.
The usefulness of zebrafish for understanding the human nervous system is exemplified by the articles in part 1. The virtual special issue part 2 not only covers more work using this well-established species, but also highlights that other fish species may serve as alternative or more appropriate models, due to unique biological or evolutionary characteristics, to explore genetic and molecular mechanisms of neurological and psychiatric disorders.
View Article and Find Full Text PDFEnviron Toxicol
January 2025
Biochemistry and Molecular Biology Program, School of Integrative Biological and Chemical Sciences, University of Texas Rio Grande Valley, Brownsville, Texas, USA.
Roundup is one of the most widely used glyphosate-based harmful herbicides in the United States as well as globally, which poses a severe risk for terrestrial and aquatic organisms. In order to identify the detrimental effects of Roundup exposure in aquatic organisms, we investigated the environmentally relevant concentrations of Roundup exposure (low dose: 0.5 μg/L and high dose: 5.
View Article and Find Full Text PDFConserv Biol
January 2025
UMR ENTROPIE (IRD, UR, CNRS, IFREMER, UNC), CS 41096, La Reunion, France.
Predatory and large-bodied coral reef fishes have fundamental roles in the functioning and biodiversity of coral reef ecosystems, but their populations are declining, largely due to overexploitation in fisheries. These fishes include sharks, groupers, Humphead wrasse (Cheilinus undulatus), and Green Humphead parrotfish (Bolbometopon muricatum). In the western Indian Ocean, this situation is exacerbated by limited population data on these fishes, including from conventional visual census methods, which limit the surface area surveyed.
View Article and Find Full Text PDFActa Parasitol
January 2025
Laboratory of Morpho-Molecular Integration and Technologies (LIMT), Federal Rural University of the Amazon (UFRA), Belém, Pará, Brazil.
Background: Freshwater fish are affected with much parasitic diseases, among the most common are Henneguyosis caused by myxozoans of the genus Henneguya, which exhibit great diversity in fish from South America, particularly in the Brazilian Amazon.
Purpose: In this present study, we describe the morphological and phylogenetic aspects of the small ribosomal subunit (SSU rDNA) of two new species of Henneguya infecting the gills from Hypophthalmus marginatus, a freshwater catfish from the Amazon.
Methods: In 148 specimens, has been observed cyst formation in different regions of the gills, intrafilamentary and intralamellar.
Environ Sci Pollut Res Int
January 2025
Department of Chemistry, University of Pretoria, Hatfield, Pretoria, South Africa.
Pollution in marine creeks has been increasing due to anthropogenic activities and has been a global concern. Limited research has been conducted on pharmaceuticals in marine sediment and macroalgae in African countries. In the present study, the levels of pharmaceuticals were assessed in surface sediment and different species of macroalgae (ulvophyceae; Cladophora sudanensis, Chaetomorpha crassa, Chaetomorpha indica, Enteromorpha kylinii, Ulva reticulate, Ulva lactuca and Cladophora sibugae) in Mombasa peri-urban creeks (Tudor, Makupa and Mtwapa creek) and Gazi bay during dry and wet seasons.
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