Search results for "phylogenetic tree"
showing 10 items of 557 documents
Species complexes and phylogenetic lineages of Hoferellus (Myxozoa, Cnidaria) including revision of the genus: A problematic case for taxonomy
2015
Background Myxozoans are metazoan parasites whose traditional spore morphology-based taxonomy conflicts DNA based phylogenies. Freshwater species of the genus Hoferellus are parasites of the excretory system, with several members infecting food and ornamental fish species, as well as amphibians. This study aims to increase our understanding of their molecular diversity and development, aspects about which little is known, and to generate a molecular diagnostic tool to discriminate between different pathogenic and non-pathogenic Hoferellus spp. Methods SSU and ITS rDNA phylogeny, along with morphological descriptions using light and electron microscopy were used to identify and characterize …
Introduction of an single nucleodite polymorphism-based “Major Y-chromosome haplogroup typing kit” suitable for predicting the geographical origin of…
2005
The European Consortium "High-throughput analysis of single nucleotide polymorphisms for the forensic identification of persons--SNPforID", has performed a selection of candidate Y-chromosome single nucleotide polymorphisms (SNPs) for making inferences on the geographic origin of an unknown sample. From more than 200 SNPs compiled in the phylogenetic tree published by the Y-Chromosome Consortium, and looking at the population studies previously published, a package of 29 SNPs has been selected for the identification of major population haplogroups. A "Major Y-chromosome haplogroup typing kit" has been developed, which allows the multiplex amplification of all 29 SNPs in a single reaction. A…
Cardicola aurata sp. n. (Digenea: Sanguinicolidae) from Mediterranean Sparus aurata L. (Teleostei: Sparidae) and its unexpected phylogenetic relation…
2008
A new sanguinicolid trematode, Cardicola aurata sp. n., is described from gilthead seabream Sparus aurata L., from off the Spanish Mediterranean coast. The morphology of C. aurata sp. n. generally agrees with the diagnosis of the genus, however, in contrast to all other reported Cardicola spp. the male pore is located sub-medially at the posterior end of the body instead of sinistrally before the posterior end of the body. Based on a comparison of the morphology as well as partial 28S and ITS2 rDNA sequence data from the present species with that from closely related species, it was decided to emend the diagnosis of Cardicola rather than create a new genus, as the aberrant position of the m…
Genes coding for intermediate filament proteins closely related to the hagfish "thread keratins (TK)" alpha and gamma also exist in lamprey, teleosts…
2005
The "thread keratins (TK)" alpha and gamma so far have been considered highly specialized intermediate filament (IF) proteins restricted to hagfish. From lamprey, we now have sequenced five novel IF proteins closely related to TKalpha and TKgamma, respectively. Moreover, we have detected corresponding sequences in EST and genomic databases of teleosts and amphibians. The structure of the TKalpha genes and the positions of their deduced amino acid sequences in a phylogenetic tree clearly support their classification as type II keratins. The genes encoding TKgamma show a structure typical for type III IF proteins, whereas their positions in phylogenetic trees favor a close relationship to the…
Weak phylogenetic effects on ecological niches of Sylvia warblers
2003
To understand the evolution of ecological niches it is important to know whether niche evolution is constrained by phylogeny. We approached this question for Sylvia warblers by testing if closely related species are more similar in 20 ecologically relevant morphological traits than distantly related species. Phylogenetic relatedness was quantified using a molecular phylogeny based on the mitochondrial cytochrome b gene. By Principal Component Analysis (PCA) two major niche axes were extracted. We tested the individual ecomorphological traits and the positions of the species on the PCA axes for phylogenetic effects using Mantel tests. The results demonstrated small but significant phylogenet…
Revision of the Shore-fly Genera Parahyadina Tonnoir and Malloch and New Zealand Hyadina Haliday (Diptera: Ephydridae).
2019
Two genera of the shore-fly tribe Hyadinini, Hyadina Haliday and Parahyadina Tonnoir & Malloch, are revised, and all species treated, save P. lacustris Tonnoir & Malloch, are described for the first time. The phylogenetic position of both genera within Hyadinini is presented along with confirming, morphological evidence. The New Zealand fauna of Hyadina is now limited to the single new species H. breva, and Parahyadina is expanded from being a monotypic genus based on P. lacustris to also include the following 9 endemic new species: P. angusta, P. atra, P. bifurcata, P. bulla, P. debilis, P. edmistoni, P. hennigi, P. irwini, and P. latistylis. For both genera, emphasis is given to s…
Escherichia coli of human and avian origin: detection of clonal groups associated with fluoroquinolone and multidrug resistance in Italy
2012
Objectives: Poultry have been suggested as a reservoir for fluoroquinolone-resistant extraintestinal pathogenic Escherichia coli (ExPEC). Our aim was to investigate whether genotypes associated with ciprofloxacin and multidrug resistance were shared among human and avian E. coli. Methods: We compared 277 human ExPEC isolates from urinary tract infection (UTI) and sepsis (142 susceptible and 135 ciprofloxacin resistant) and 101 avian isolates (68 susceptible and 33 ciprofloxacin resistant) by antimicrobial resistance phenotype, phylogenetic group and multilocus sequence type (ST). Results: Most ciprofloxacin-resistant isolates from both human and avian sources were multidrug resistant. Human…
Facial patterns in Cercopithecoidea and Hominoidea: a geometric approach.
2006
The maxillofacial and orbital compartments of the primate skull contribute to the ontogenetic and phylogenetic variability of the viscerocranium and are of crucial evolutionary relevance. As the form of organisms changes depending on endo- and exogenous factors, metrical evaluation of specific adaptations and incorporation of the results into a biological framework could be helpful in identifying valid characters for separation of taxa (e.g. family, genus, and species) and in understanding divergence and convergence. During the last two decades a morphometric "revolution" heralded by Rohlf & Marcus (1993), Adams et al. (2004) and Oxnard (2004) brought about a synthesis of traditional quanti…
Lung-worms (Nematoda: Pseudaliidae) of harbour porpoises (Phocoena phocoena) in Norwegian waters: patterns of colonization
1994
SUMMARYWe studied the component community of lung-worms of the harbour porpoise, attempting to establish the relative importance of ecological and evolutionary factors on its development. The lungs of 64 porpoises by-caught in Norwegian waters were examined for helminths. Three pseudaliid species were detected. The porpoises appear to be readily colonized by lung-worms, the structure of the component community of calves being fairly similar to that of the remainder. Prenatal and/or transmammary infections might partly account for these early infections. However, host age was correlated with the number of lung-worm species, suggesting that the lung-worms may have heteroxenous cycles similar …
Phylogenetic reconstruction of HCV genotype 1b dissemination in a small city centre: The Camporeale model
2008
Several seroepidemiological population-based surveys carried out in Italy have shown a high prevalence of hepatitis C virus (HCV) infection. Camporeale (CP), a small Sicilian town with a 10.4% prevalence of HCV mostly genotype 1b, probably represents a specific context, since intravenous drug addiction, and sexual promiscuity are almost absent. In order to reconstruct the pattern of introduction and diffusion of HCV in this ecological niche, the NS5 genomic region of 72 HCV genotype 1 isolates (39 from CP and 33 collected throughout Sicily) was amplified and sequenced. Sequences were aligned and analyzed by BioEdit, PAUP and BEAST, and their molecular evolution compared. Thirty-eight HCV ge…