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Harald Ahnelt - One of the best experts on this subject based on the ideXlab platform.
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European minnows through time: museum collections aid genetic assessment of species introductions in freshwater fishes (Cyprinidae: Phoxinus species complex)
Heredity, 2020Co-Authors: Anja Palandačić, Luise Kruckenhauser, Harald Ahnelt, Ernst MikschiAbstract:Massive fish introductions have taken place throughout much of the world, mostly over the last 70 years, and present a major threat to the genetic diversity of native fishes. Introductions have been reported for European Phoxinus , a ubiquitous small cyprinid that populates a wide variety of habitats. Species delineation in European Phoxinus has proven difficult with one reason being ranges of distribution that often traverse drainage boundaries. The present study combines recent samples with museum samples to better understand the current distribution of Phoxinus species and their distributions prior to the massive introductions of fishes in Europe, and to evaluate the use of museum specimens for species distribution studies. For these purposes, genetic lineages from sites collected prior to 1900 ( n = 14), and between 1900 and 1950 ( n = 8), were analysed using two mitochondrial and nuclear markers. Although possible fish introductions were detected, our results show that the distribution of genetic lineages of museum samples is comparable to that of the extant lineages of European Phoxinus present in those areas. These observations suggest that in the studied ranges the distribution of Phoxinus lineages has been driven by natural processes.
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contrasting morphology with molecular data an approach to revision of species complexes based on the example of european Phoxinus cyprinidae
BMC Evolutionary Biology, 2017Co-Authors: Anja Palandacic, Harald Ahnelt, Alexander Naseka, David RamlerAbstract:Molecular taxonomy studies and barcoding projects can provide rapid means of detecting cryptic diversity. Nevertheless, the use of molecular data for species delimitation should be undertaken with caution. Especially the single-gene approaches are linked with certain pitfalls for taxonomical inference. In the present study, recent and historical species descriptions based upon morphology were used as primary species hypotheses, which were then evaluated with molecular data (including in type and historical museum material) to form secondary species hypotheses. As an example of cryptic diversity and taxonomic controversy, the European Phoxinus Phoxinus species complex was used. The results of the revision showed that of the fourteen primary species hypotheses, three were rejected, namely P. ketmaieri, P. likai, and P. apollonicus. For three species (P. strandjae, P. strymonicus, P. morella), further investigation with increased data sampling was suggested, while two primary hypotheses, P. bigerri and P. colchicus, were supported as secondary species hypotheses. Finally, six of the primary species hypotheses (P. Phoxinus, P. lumaireul, P. karsticus, P. septimanae, P. marsilii and P. csikii) were well supported by mitochondrial but only limitedly corroborated by nuclear data analysis. The approach has proven useful for revision of species complexes, and the study can serve as an overview of the Phoxinus genus in Europe, as well as a solid basis for further work.
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Corrigendum to «Contrasting morphology with molecular data: an approach to revision of species complexes based on the example of European (Cyprinidae)» by Palandačić et al. 2017.
Pensoft Publishers, 2017Co-Authors: Anja Palandacic, Alexander Naseka, David Ramler, Harald AhneltAbstract:This corrigendum, in the sense of the Glossary of the International Code of Zoological Nomenclature (ICZN 1999, p. 102), is to ensure that the ICZN criteria for the availability of the two new nomenclatural acts, namely the designations of the neotype of Phoxinus csikii Hankó, 1922 and the lectotype of Phoxinus marsilii Heckel, 1836, are satisfied
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morphological divergence of lake and stream Phoxinus of northern italy and the danube basin based on geometric morphometric analysis
Ecology and Evolution, 2017Co-Authors: Harald Ahnelt, Anja Palandacic, David Ramler, Giovanni B Delmastro, Josef WanzenbockAbstract:Minnows of the genus Phoxinus are promising candidates to investigate adaptive divergence, as they inhabit both still and running waters of a variety of altitudes and climatic zones in Europe. We used landmark-based geometric morphometric methods to quantify the level of morphological variability in Phoxinus populations from streams and lakes of Northern Italy and the Danube basin. We analyzed body shape differences of populations in the dorsal, lateral, and ventral planes, using a large array of landmarks and semilandmarks. As the species identification of Phoxinus on morphological characters is ambiguous, we used two mitochondrial genes to determine the genetic background of the samples and to ensure we are comparing homogenous groups. We have found significant body shape differences between habitats: Minnow populations inhabiting streams had a deeper body and caudal peduncle and more laterally inserted pectoral fins than minnows inhabiting lakes. We have also found significant body shape differences between genetic groups: Italian minnows had deeper bodies, deeper and shorter caudal peduncles, and a shorter and wider gape than both groups from the Danube. Our results show that the morphology of Phoxinus is highly influenced by habitat and that body shape variation between habitats was within the same range as between genetic groups. These morphological differences are possibly linked to different modes of swimming and foraging in the respective habitats and are likely results of phenotypic plasticity. However, differences in shape and interlandmark distances between the groups suggest that some (though few) morphometric characters might be useful for separating Phoxinus species.
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Contrasting morphology with molecular data: an approach to revision of species complexes based on the example of European Phoxinus (Cyprinidae)
BMC, 2017Co-Authors: Anja Palandačić, Alexander Naseka, David Ramler, Harald AhneltAbstract:Abstract Background Molecular taxonomy studies and barcoding projects can provide rapid means of detecting cryptic diversity. Nevertheless, the use of molecular data for species delimitation should be undertaken with caution. Especially the single-gene approaches are linked with certain pitfalls for taxonomical inference. In the present study, recent and historical species descriptions based upon morphology were used as primary species hypotheses, which were then evaluated with molecular data (including in type and historical museum material) to form secondary species hypotheses. As an example of cryptic diversity and taxonomic controversy, the European Phoxinus Phoxinus species complex was used. Results The results of the revision showed that of the fourteen primary species hypotheses, three were rejected, namely P. ketmaieri, P. likai, and P. apollonicus. For three species (P. strandjae, P. strymonicus, P. morella), further investigation with increased data sampling was suggested, while two primary hypotheses, P. bigerri and P. colchicus, were supported as secondary species hypotheses. Finally, six of the primary species hypotheses (P. Phoxinus, P. lumaireul, P. karsticus, P. septimanae, P. marsilii and P. csikii) were well supported by mitochondrial but only limitedly corroborated by nuclear data analysis. Conclusion The approach has proven useful for revision of species complexes, and the study can serve as an overview of the Phoxinus genus in Europe, as well as a solid basis for further work
David Ramler - One of the best experts on this subject based on the ideXlab platform.
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contrasting morphology with molecular data an approach to revision of species complexes based on the example of european Phoxinus cyprinidae
BMC Evolutionary Biology, 2017Co-Authors: Anja Palandacic, Harald Ahnelt, Alexander Naseka, David RamlerAbstract:Molecular taxonomy studies and barcoding projects can provide rapid means of detecting cryptic diversity. Nevertheless, the use of molecular data for species delimitation should be undertaken with caution. Especially the single-gene approaches are linked with certain pitfalls for taxonomical inference. In the present study, recent and historical species descriptions based upon morphology were used as primary species hypotheses, which were then evaluated with molecular data (including in type and historical museum material) to form secondary species hypotheses. As an example of cryptic diversity and taxonomic controversy, the European Phoxinus Phoxinus species complex was used. The results of the revision showed that of the fourteen primary species hypotheses, three were rejected, namely P. ketmaieri, P. likai, and P. apollonicus. For three species (P. strandjae, P. strymonicus, P. morella), further investigation with increased data sampling was suggested, while two primary hypotheses, P. bigerri and P. colchicus, were supported as secondary species hypotheses. Finally, six of the primary species hypotheses (P. Phoxinus, P. lumaireul, P. karsticus, P. septimanae, P. marsilii and P. csikii) were well supported by mitochondrial but only limitedly corroborated by nuclear data analysis. The approach has proven useful for revision of species complexes, and the study can serve as an overview of the Phoxinus genus in Europe, as well as a solid basis for further work.
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Corrigendum to «Contrasting morphology with molecular data: an approach to revision of species complexes based on the example of European (Cyprinidae)» by Palandačić et al. 2017.
Pensoft Publishers, 2017Co-Authors: Anja Palandacic, Alexander Naseka, David Ramler, Harald AhneltAbstract:This corrigendum, in the sense of the Glossary of the International Code of Zoological Nomenclature (ICZN 1999, p. 102), is to ensure that the ICZN criteria for the availability of the two new nomenclatural acts, namely the designations of the neotype of Phoxinus csikii Hankó, 1922 and the lectotype of Phoxinus marsilii Heckel, 1836, are satisfied
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morphological divergence of lake and stream Phoxinus of northern italy and the danube basin based on geometric morphometric analysis
Ecology and Evolution, 2017Co-Authors: Harald Ahnelt, Anja Palandacic, David Ramler, Giovanni B Delmastro, Josef WanzenbockAbstract:Minnows of the genus Phoxinus are promising candidates to investigate adaptive divergence, as they inhabit both still and running waters of a variety of altitudes and climatic zones in Europe. We used landmark-based geometric morphometric methods to quantify the level of morphological variability in Phoxinus populations from streams and lakes of Northern Italy and the Danube basin. We analyzed body shape differences of populations in the dorsal, lateral, and ventral planes, using a large array of landmarks and semilandmarks. As the species identification of Phoxinus on morphological characters is ambiguous, we used two mitochondrial genes to determine the genetic background of the samples and to ensure we are comparing homogenous groups. We have found significant body shape differences between habitats: Minnow populations inhabiting streams had a deeper body and caudal peduncle and more laterally inserted pectoral fins than minnows inhabiting lakes. We have also found significant body shape differences between genetic groups: Italian minnows had deeper bodies, deeper and shorter caudal peduncles, and a shorter and wider gape than both groups from the Danube. Our results show that the morphology of Phoxinus is highly influenced by habitat and that body shape variation between habitats was within the same range as between genetic groups. These morphological differences are possibly linked to different modes of swimming and foraging in the respective habitats and are likely results of phenotypic plasticity. However, differences in shape and interlandmark distances between the groups suggest that some (though few) morphometric characters might be useful for separating Phoxinus species.
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Contrasting morphology with molecular data: an approach to revision of species complexes based on the example of European Phoxinus (Cyprinidae)
BMC, 2017Co-Authors: Anja Palandačić, Alexander Naseka, David Ramler, Harald AhneltAbstract:Abstract Background Molecular taxonomy studies and barcoding projects can provide rapid means of detecting cryptic diversity. Nevertheless, the use of molecular data for species delimitation should be undertaken with caution. Especially the single-gene approaches are linked with certain pitfalls for taxonomical inference. In the present study, recent and historical species descriptions based upon morphology were used as primary species hypotheses, which were then evaluated with molecular data (including in type and historical museum material) to form secondary species hypotheses. As an example of cryptic diversity and taxonomic controversy, the European Phoxinus Phoxinus species complex was used. Results The results of the revision showed that of the fourteen primary species hypotheses, three were rejected, namely P. ketmaieri, P. likai, and P. apollonicus. For three species (P. strandjae, P. strymonicus, P. morella), further investigation with increased data sampling was suggested, while two primary hypotheses, P. bigerri and P. colchicus, were supported as secondary species hypotheses. Finally, six of the primary species hypotheses (P. Phoxinus, P. lumaireul, P. karsticus, P. septimanae, P. marsilii and P. csikii) were well supported by mitochondrial but only limitedly corroborated by nuclear data analysis. Conclusion The approach has proven useful for revision of species complexes, and the study can serve as an overview of the Phoxinus genus in Europe, as well as a solid basis for further work
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Additional file 1: Table S1. of Contrasting morphology with molecular data: an approach to revision of species complexes based on the example of European Phoxinus (Cyprinidae)
2017Co-Authors: Anja Palandačić, Alexander Naseka, David Ramler, Harald AhneltAbstract:Characters used in the literature for distinguishing species/subspecies of P. Phoxinus s.l. (XLS 39 kb
Jean-nicolas Beisel - One of the best experts on this subject based on the ideXlab platform.
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glochidial infestation by the endangered mollusc unio crassus in rivers of north eastern france Phoxinus Phoxinus and cottus gobio as primary fish hosts
Aquatic Conservation-marine and Freshwater Ecosystems, 2016Co-Authors: Florent Lamand, Kevin Roche, Jean-nicolas BeiselAbstract:The thick-shelled river mussel Unio crassus is an endangered freshwater bivalve species with a life cycle that includes an obligate glochidial larval stage that attaches to the gills of freshwater fish for several days to months. Fish hosts were identified in nine north-eastern French rivers in order to improve unionid conservation management. Eurasian minnow Phoxinus Phoxinus was the most important host at all study sites, with prevalence ranging from 15–100% (122 of 238 individuals infested), and bullhead Cottus gobio usually the second most important (prevalence 0–73%; 37 of 121). Other host species had a relatively low rate of infestation: chub Squalius cephalus (5 of 41), roach Rutilus rutilus (1 of 23), gudgeon Gobio gobio (2 of 50), stone loach Barbatula barbatula (2 of 58) and dace Leuciscus leuciscus (1 of 19). No glochidia were found on spirlin Alburnoides bipunctatus (0 of 24). Parasitic load usually ranged between one and three per fish (60% of cases), and rarely exceeded 10. First results suggest that U. crassus glochidia influence the weight:length ratio of P. Phoxinus but not C. gobio, with infested fish being heavier. To date, the ecological function of P. Phoxinus (and C. gobio) in small streams has been largely underestimated or ignored as the species is small, common and of no interest to anglers. There is increasing evidence, however, that P. Phoxinus deserves conservation management owing to the essential role it plays in the reproduction, development and distribution of U. crassus. Copyright © 2016 John Wiley & Sons, Ltd.
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Glochidial infestation by the endangered mollusc Unio crassus in rivers of north‐eastern France: Phoxinus Phoxinus and Cottus gobio as primary fish hosts
Aquatic Conservation: Marine and Freshwater Ecosystems, 2016Co-Authors: Florent Lamand, Kevin Roche, Jean-nicolas BeiselAbstract:The thick-shelled river mussel Unio crassus is an endangered freshwater bivalve species with a life cycle that includes an obligate glochidial larval stage that attaches to the gills of freshwater fish for several days to months. Fish hosts were identified in nine north-eastern French rivers in order to improve unionid conservation management. Eurasian minnow Phoxinus Phoxinus was the most important host at all study sites, with prevalence ranging from 15–100% (122 of 238 individuals infested), and bullhead Cottus gobio usually the second most important (prevalence 0–73%; 37 of 121). Other host species had a relatively low rate of infestation: chub Squalius cephalus (5 of 41), roach Rutilus rutilus (1 of 23), gudgeon Gobio gobio (2 of 50), stone loach Barbatula barbatula (2 of 58) and dace Leuciscus leuciscus (1 of 19). No glochidia were found on spirlin Alburnoides bipunctatus (0 of 24). Parasitic load usually ranged between one and three per fish (60% of cases), and rarely exceeded 10. First results suggest that U. crassus glochidia influence the weight:length ratio of P. Phoxinus but not C. gobio, with infested fish being heavier. To date, the ecological function of P. Phoxinus (and C. gobio) in small streams has been largely underestimated or ignored as the species is small, common and of no interest to anglers. There is increasing evidence, however, that P. Phoxinus deserves conservation management owing to the essential role it plays in the reproduction, development and distribution of U. crassus. Copyright © 2016 John Wiley & Sons, Ltd.
Anja Palandačić - One of the best experts on this subject based on the ideXlab platform.
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European minnows through time: museum collections aid genetic assessment of species introductions in freshwater fishes (Cyprinidae: Phoxinus species complex)
Heredity, 2020Co-Authors: Anja Palandačić, Luise Kruckenhauser, Harald Ahnelt, Ernst MikschiAbstract:Massive fish introductions have taken place throughout much of the world, mostly over the last 70 years, and present a major threat to the genetic diversity of native fishes. Introductions have been reported for European Phoxinus , a ubiquitous small cyprinid that populates a wide variety of habitats. Species delineation in European Phoxinus has proven difficult with one reason being ranges of distribution that often traverse drainage boundaries. The present study combines recent samples with museum samples to better understand the current distribution of Phoxinus species and their distributions prior to the massive introductions of fishes in Europe, and to evaluate the use of museum specimens for species distribution studies. For these purposes, genetic lineages from sites collected prior to 1900 ( n = 14), and between 1900 and 1950 ( n = 8), were analysed using two mitochondrial and nuclear markers. Although possible fish introductions were detected, our results show that the distribution of genetic lineages of museum samples is comparable to that of the extant lineages of European Phoxinus present in those areas. These observations suggest that in the studied ranges the distribution of Phoxinus lineages has been driven by natural processes.
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Contrasting morphology with molecular data: an approach to revision of species complexes based on the example of European Phoxinus (Cyprinidae)
BMC, 2017Co-Authors: Anja Palandačić, Alexander Naseka, David Ramler, Harald AhneltAbstract:Abstract Background Molecular taxonomy studies and barcoding projects can provide rapid means of detecting cryptic diversity. Nevertheless, the use of molecular data for species delimitation should be undertaken with caution. Especially the single-gene approaches are linked with certain pitfalls for taxonomical inference. In the present study, recent and historical species descriptions based upon morphology were used as primary species hypotheses, which were then evaluated with molecular data (including in type and historical museum material) to form secondary species hypotheses. As an example of cryptic diversity and taxonomic controversy, the European Phoxinus Phoxinus species complex was used. Results The results of the revision showed that of the fourteen primary species hypotheses, three were rejected, namely P. ketmaieri, P. likai, and P. apollonicus. For three species (P. strandjae, P. strymonicus, P. morella), further investigation with increased data sampling was suggested, while two primary hypotheses, P. bigerri and P. colchicus, were supported as secondary species hypotheses. Finally, six of the primary species hypotheses (P. Phoxinus, P. lumaireul, P. karsticus, P. septimanae, P. marsilii and P. csikii) were well supported by mitochondrial but only limitedly corroborated by nuclear data analysis. Conclusion The approach has proven useful for revision of species complexes, and the study can serve as an overview of the Phoxinus genus in Europe, as well as a solid basis for further work
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Additional file 1: Table S1. of Contrasting morphology with molecular data: an approach to revision of species complexes based on the example of European Phoxinus (Cyprinidae)
2017Co-Authors: Anja Palandačić, Alexander Naseka, David Ramler, Harald AhneltAbstract:Characters used in the literature for distinguishing species/subspecies of P. Phoxinus s.l. (XLS 39 kb
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Molecular data suggest a multispecies complex of Phoxinus (Cyprinidae) in the Western Balkan Peninsula.
Molecular phylogenetics and evolution, 2015Co-Authors: Anja Palandačić, Jernej Bravničar, Primož Zupančič, Radek Šanda, Aleš SnojAbstract:Abstract This study aimed to evaluate the phylogeographic distribution of Phoxinus Phoxinus sensu lato populations in the Balkan Peninsula using molecular methods. For the western Balkan Peninsula, two species (Danubian P. Phoxinus and Adriatic P. lumaireul ) have been suggested, but not confirmed by subsequent morphological studies or by genetic data. For the present study, more than 300 specimens were collected from the western Balkans. A partial sequence of the mt cyt b gene analysed using Bayesian and ML methods revealed several well-supported clades, with distances ranging from 4% to 11%. The clades were corroborated by RAG1 sequence analysis. Thus, the molecular analysis points to a multispecies complex of Phoxinus sp. with ranges of the clades extending north-west to south-east along the western Balkan Peninsula. In addition, the dispersion of fish through subterranean water connections in karst is indicated.
Jonathan A Mee - One of the best experts on this subject based on the ideXlab platform.
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repeat swimming performance and its implications for inferring the relative fitness of asexual hybrid dace pisces Phoxinus and their sexually reproducing parental species
Physiological and Biochemical Zoology, 2011Co-Authors: Jonathan A Mee, Colin J Brauner, Eric B TaylorAbstract:AbstractWhile theories explaining the evolution and maintenance of sex are abundant, empirical data on the costs and benefits of asexual relative to sexual reproduction are less common. Asexually reproducing vertebrates, while few, provide a rare opportunity to measure differences in fitness between asexual and sexual species. All known asexually reproducing vertebrates are of hybrid origin, and hybrid disadvantage (i.e., reduced hybrid fitness) is thought to facilitate long-term coexistence between asexual and sexual species. We used repeat swimming performance as a proxy for fitness to compare the fitness of asexual hybrid dace (Pisces: Phoxinus) and their sexually reproducing parental species, finescale dace (Phoxinus neogaeus) and northern redbelly dace (Phoxinus eos). We tested the prediction that, given the widespread coexistence of these hybrid and parental dace, the parental species should show equivalent and perhaps superior repeat performance relative to hybrids. A repeat constant acceleration t...
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Distribution of Phoxinus eos, Phoxinus neogaeus, and their asexually-reproducing hybrids (Pisces: Cyprinidae) in Algonquin Provincial Park, Ontario.
PloS one, 2010Co-Authors: Jonathan A Mee, Locke RoweAbstract:Hybrid Phoxinus are one of the few asexually reproducing vertebrates species. The distribution of hybrid Phoxinus among lakes in Algonquin Park, Ontario, was evaluated relative to the distribution of parental species and relative to physiochemical lake characteristics. No association between the distribution of hybrids and the distribution of parental species was found, suggesting that the hybrids can successfully coexist with either parental species. In addition, we found no association between hybrid distribution and the physiochemical characteristics of lakes, suggesting that the hybrids are generalists with respect to the ecological niches available in Algonquin Park. There was a difference between the physiochemical characteristics of lakes with and without the parental species P. neogaeus. The lakes containing P. neogaeus were lower elevation than the lakes containing the other parental species, P. eos. The difference in distribution between the parental species may therefore be due to different dispersal abilities, to later arrival following post-glacial dispersal, or to differences in ecology. These results suggest that asexual reproduction is a successful strategy for hybrid Phoxinus in Algonquin Park because these sperm-dependent asexual hybrids are able to survive and persist regardless of which parental species is present, and regardless of the physiochemical characteristics of their habitat.