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Michel Sartori - One of the best experts on this subject based on the ideXlab platform.

  • Molecular phylogeny and timing of diversification in Alpine Rhithrogena (Ephemeroptera: Heptageniidae).
    BMC evolutionary biology, 2016
    Co-Authors: Laurent Vuataz, Michael T. Monaghan, Sereina Rutschmann, Michel Sartori
    Abstract:

    Larvae of the Holarctic mayfly genus Rhithrogena Eaton, 1881 (Ephemeroptera, Heptageniidae) are a diverse and abundant member of stream and river communities and are routinely used as bio-indicators of water quality. Rhithrogena is well diversified in the European Alps, with a number of locally endemic species, and several cryptic species have been recently detected. While several informal species groups are morphologically well defined, a lack of reliable characters for species identification considerably hampers their study. Their relationships, origin, timing of speciation and mechanisms promoting their diversification in the Alps are unknown. Here we present a species-level phylogeny of Rhithrogena in Europe using two mitochondrial and three nuclear gene regions. To improve sampling in a genus with many cryptic species, individuals were selected for analysis according to a recent DNA-based taxonomy rather than traditional nomenclature. A coalescent-based species tree and a reconstruction based on a supermatrix approach supported five of the species groups as monophyletic. A molecular clock, mapped on the most resolved phylogeny and calibrated using published mitochondrial evolution rates for insects, suggested an origin of Alpine Rhithrogena in the Oligocene/Miocene boundary. A diversification analysis that included simulation of missing species indicated a constant speciation rate over time, rather than any pronounced periods of rapid speciation. Ancestral state reconstructions provided evidence for downstream diversification in at least two species groups. Our species-level analyses of five gene regions provide clearer definitions of species groups within European Rhithrogena. A constant speciation rate over time suggests that the paleoclimatic fluctuations, including the Pleistocene glaciations, did not significantly influence the tempo of diversification of Alpine species. A downstream diversification trend in the hybrida and alpestris species groups supports a previously proposed headwater origin hypothesis for aquatic insects.

  • What is Ecdyonurus sumatranus Ulmer, 1939? A contribution to the knowledge of the genus Rhithrogena in the Oriental Region (Ephemeroptera, Heptageniidae)
    Zootaxa, 2014
    Co-Authors: Michel Sartori
    Abstract:

    The species Ecdyonurus sumatranus Ulmer, 1939 was described from Sumatra based on a female imago and a single nymph. It was designated as the type-species of the genus Ecdyonuroides Dang, 1967, erected because of the peculiar morphology of the nymph. This genus was put into synonymy later and the species is currently known as Thalerosphyrus sumatranus (Ulmer, 1939). The female imago holotype of Ecdyonurus sumatranus Ulmer, 1939 is reinvestigated and revealed to belong to the genus Rhithrogena Eaton, 1881. The combination Rhithrogena sumatrana (Ulmer, 1939) comb. nov. is thus proposed. The nymphs described by Ulmer (1939) from Java sub. nom. Rhithrogena parva (?) are associated to this species, and are redescribed with new material coming from Java and Lombok. Rhithrogena parva (Ulmer, 1912) is redescribed based on the syntype series from Taiwan and male genitalia are illustrated for the first time. Supplementary description is provided for the nymph of Rh. parva and for the one of Rh. ampla Kang & Yang, 1994, also from Taiwan. The status of the subgenus Tumungula Zhou & Peters, 2004 is briefly discussed. The nymph associated by Ulmer (1939) to Ecdyonurus sumatranus is renamed Thalerosphyrus lamuriensis sp. nov. The genus Ecdyonuroides Dang, 1967 is considered as a synonym of Rhithrogena syn. nov.

  • what is ecdyonurus sumatranus ulmer 1939 a contribution to the knowledge of the genus Rhithrogena in the oriental region ephemeroptera heptageniidae
    Zootaxa, 2014
    Co-Authors: Michel Sartori
    Abstract:

    The species Ecdyonurus sumatranus Ulmer, 1939 was described from Sumatra based on a female imago and a single nymph. It was designated as the type-species of the genus Ecdyonuroides Dang, 1967, erected because of the peculiar morphology of the nymph. This genus was put into synonymy later and the species is currently known as Thalerosphyrus sumatranus (Ulmer, 1939). The female imago holotype of Ecdyonurus sumatranus Ulmer, 1939 is reinvestigated and revealed to belong to the genus Rhithrogena Eaton, 1881. The combination Rhithrogena sumatrana (Ulmer, 1939) comb. nov. is thus proposed. The nymphs described by Ulmer (1939) from Java sub. nom. Rhithrogena parva (?) are associated to this species, and are redescribed with new material coming from Java and Lombok. Rhithrogena parva (Ulmer, 1912) is redescribed based on the syntype series from Taiwan and male genitalia are illustrated for the first time. Supplementary description is provided for the nymph of Rh. parva and for the one of Rh. ampla Kang & Yang, 1994, also from Taiwan. The status of the subgenus Tumungula Zhou & Peters, 2004 is briefly discussed. The nymph associated by Ulmer (1939) to Ecdyonurus sumatranus is renamed Thalerosphyrus lamuriensis sp. nov. The genus Ecdyonuroides Dang, 1967 is considered as a synonym of Rhithrogena syn. nov.

  • MT: Toward a DNA taxonomy of alpine Rhithrogena (Ephemeroptera: Heptageniidae) using a mixed Yulecoalescent analysis of mitochondrial and nuclear DNA. PLoS One 2011
    2013
    Co-Authors: Laurent Vuataz, Michel Sartori, André Wagner, Michael T. Monaghan
    Abstract:

    Aquatic larvae of many Rhithrogena mayflies (Ephemeroptera) inhabit sensitive Alpine environments. A number of species are on the IUCN Red List and many recognized species have restricted distributions and are of conservation interest. Despite their ecological and conservation importance, ambiguous morphological differences among closely related species suggest that the current taxonomy may not accurately reflect the evolutionary diversity of the group. Here we examined the species status of nearly 50 % of European Rhithrogena diversity using a widespread sampling scheme of Alpine species that included 22 type localities, general mixed Yule-coalescent (GMYC) model analysis of one standard mtDNA marker and one newly developed nDNA marker, and morphological identification where possible. Using sequences from 533 individuals from 144 sampling localities, we observed significant clustering of the mitochondrial (cox1) marker into 31 GMYC species. Twenty-one of these could be identified based on the presence of topotypes (expertly identified specimens from the species ’ type locality) or unambiguous morphology. These results strongly suggest the presence of both cryptic diversity and taxonomic oversplitting in Rhithrogena. Significant clustering was not detected with protein-coding nuclear PEPCK, although nine GMYC species were congruent with well supported terminal clusters of nDNA. Lack of greater congruence in the two data sets may be the result of incomplete sorting of ancestral polymorphism. Bayesian phylogenetic analyses of both gene regions recovered four of the six recognized Rhithrogena species groups in our samples as monophyletic. Futur

  • Bayesian majority-rule consensus tree of the reduced PEPCK data set obtained using MrBayes.
    2013
    Co-Authors: Laurent Vuataz, Michel Sartori, André Wagner, Michael T. Monaghan
    Abstract:

    Lineages 1 to 4 correspond to four different Rhithrogena morphological species groups (1: alpestris; 2: loyolaea; 3: diaphana; 4: semicolorata). Lineage 5 includes clades belonging to the hercynia species group (arrows) and the hybrida species group. Triangles represent collapsed lineages, (width proportional to the number of haplotypes). Filled stars indicate posterior probabilities (PP)>0.95, open stars indicate PP>0.75.

Braasch Dietrich - One of the best experts on this subject based on the ideXlab platform.

Michael T. Monaghan - One of the best experts on this subject based on the ideXlab platform.

  • Molecular phylogeny and timing of diversification in Alpine Rhithrogena (Ephemeroptera: Heptageniidae).
    BMC evolutionary biology, 2016
    Co-Authors: Laurent Vuataz, Michael T. Monaghan, Sereina Rutschmann, Michel Sartori
    Abstract:

    Larvae of the Holarctic mayfly genus Rhithrogena Eaton, 1881 (Ephemeroptera, Heptageniidae) are a diverse and abundant member of stream and river communities and are routinely used as bio-indicators of water quality. Rhithrogena is well diversified in the European Alps, with a number of locally endemic species, and several cryptic species have been recently detected. While several informal species groups are morphologically well defined, a lack of reliable characters for species identification considerably hampers their study. Their relationships, origin, timing of speciation and mechanisms promoting their diversification in the Alps are unknown. Here we present a species-level phylogeny of Rhithrogena in Europe using two mitochondrial and three nuclear gene regions. To improve sampling in a genus with many cryptic species, individuals were selected for analysis according to a recent DNA-based taxonomy rather than traditional nomenclature. A coalescent-based species tree and a reconstruction based on a supermatrix approach supported five of the species groups as monophyletic. A molecular clock, mapped on the most resolved phylogeny and calibrated using published mitochondrial evolution rates for insects, suggested an origin of Alpine Rhithrogena in the Oligocene/Miocene boundary. A diversification analysis that included simulation of missing species indicated a constant speciation rate over time, rather than any pronounced periods of rapid speciation. Ancestral state reconstructions provided evidence for downstream diversification in at least two species groups. Our species-level analyses of five gene regions provide clearer definitions of species groups within European Rhithrogena. A constant speciation rate over time suggests that the paleoclimatic fluctuations, including the Pleistocene glaciations, did not significantly influence the tempo of diversification of Alpine species. A downstream diversification trend in the hybrida and alpestris species groups supports a previously proposed headwater origin hypothesis for aquatic insects.

  • MT: Toward a DNA taxonomy of alpine Rhithrogena (Ephemeroptera: Heptageniidae) using a mixed Yulecoalescent analysis of mitochondrial and nuclear DNA. PLoS One 2011
    2013
    Co-Authors: Laurent Vuataz, Michel Sartori, André Wagner, Michael T. Monaghan
    Abstract:

    Aquatic larvae of many Rhithrogena mayflies (Ephemeroptera) inhabit sensitive Alpine environments. A number of species are on the IUCN Red List and many recognized species have restricted distributions and are of conservation interest. Despite their ecological and conservation importance, ambiguous morphological differences among closely related species suggest that the current taxonomy may not accurately reflect the evolutionary diversity of the group. Here we examined the species status of nearly 50 % of European Rhithrogena diversity using a widespread sampling scheme of Alpine species that included 22 type localities, general mixed Yule-coalescent (GMYC) model analysis of one standard mtDNA marker and one newly developed nDNA marker, and morphological identification where possible. Using sequences from 533 individuals from 144 sampling localities, we observed significant clustering of the mitochondrial (cox1) marker into 31 GMYC species. Twenty-one of these could be identified based on the presence of topotypes (expertly identified specimens from the species ’ type locality) or unambiguous morphology. These results strongly suggest the presence of both cryptic diversity and taxonomic oversplitting in Rhithrogena. Significant clustering was not detected with protein-coding nuclear PEPCK, although nine GMYC species were congruent with well supported terminal clusters of nDNA. Lack of greater congruence in the two data sets may be the result of incomplete sorting of ancestral polymorphism. Bayesian phylogenetic analyses of both gene regions recovered four of the six recognized Rhithrogena species groups in our samples as monophyletic. Futur

  • Bayesian majority-rule consensus tree of the reduced PEPCK data set obtained using MrBayes.
    2013
    Co-Authors: Laurent Vuataz, Michel Sartori, André Wagner, Michael T. Monaghan
    Abstract:

    Lineages 1 to 4 correspond to four different Rhithrogena morphological species groups (1: alpestris; 2: loyolaea; 3: diaphana; 4: semicolorata). Lineage 5 includes clades belonging to the hercynia species group (arrows) and the hybrida species group. Triangles represent collapsed lineages, (width proportional to the number of haplotypes). Filled stars indicate posterior probabilities (PP)>0.95, open stars indicate PP>0.75.

  • Bayesian majority-rule consensus tree of the reduced cox1 data set obtained using MrBayes.
    2013
    Co-Authors: Laurent Vuataz, Michel Sartori, André Wagner, Michael T. Monaghan
    Abstract:

    Lineages 1 to 4 correspond to four different Rhithrogena morphological species groups (1: alpestris; 2: loyolaea; 3: diaphana; 4: semicolorata). Lineage 5 includes clades belonging to the hercynia species group (arrows) and the hybrida species group. Triangles represent collapsed lineages, (width proportional to the number of haplotypes). Filled stars indicate posterior probabilities (PP)>0.95, open stars indicate PP>0.75.

  • Toward a DNA Taxonomy of Alpine Rhithrogena (Ephemeroptera: Heptageniidae) Using a Mixed Yule-Coalescent Analysis of Mitochondrial and Nuclear DNA
    PloS one, 2011
    Co-Authors: Laurent Vuataz, Michel Sartori, André Wagner, Michael T. Monaghan
    Abstract:

    Aquatic larvae of many Rhithrogena mayflies (Ephemeroptera) inhabit sensitive Alpine environments. A number of species are on the IUCN Red List and many recognized species have restricted distributions and are of conservation interest. Despite their ecological and conservation importance, ambiguous morphological differences among closely related species suggest that the current taxonomy may not accurately reflect the evolutionary diversity of the group. Here we examined the species status of nearly 50% of European Rhithrogena diversity using a widespread sampling scheme of Alpine species that included 22 type localities, general mixed Yule-coalescent (GMYC) model analysis of one standard mtDNA marker and one newly developed nDNA marker, and morphological identification where possible. Using sequences from 533 individuals from 144 sampling localities, we observed significant clustering of the mitochondrial (cox1) marker into 31 GMYC species. Twenty-one of these could be identified based on the presence of topotypes (expertly identified specimens from the species' type locality) or unambiguous morphology. These results strongly suggest the presence of both cryptic diversity and taxonomic oversplitting in Rhithrogena. Significant clustering was not detected with protein-coding nuclear PEPCK, although nine GMYC species were congruent with well supported terminal clusters of nDNA. Lack of greater congruence in the two data sets may be the result of incomplete sorting of ancestral polymorphism. Bayesian phylogenetic analyses of both gene regions recovered four of the six recognized Rhithrogena species groups in our samples as monophyletic. Future development of more nuclear markers would facilitate multi-locus analysis of unresolved, closely related species pairs. The DNA taxonomy developed here lays the groundwork for a future revision of the important but cryptic Rhithrogena genus in Europe.

Boonsoong Boonsatien - One of the best experts on this subject based on the ideXlab platform.

Laurent Vuataz - One of the best experts on this subject based on the ideXlab platform.

  • Molecular phylogeny and timing of diversification in Alpine Rhithrogena (Ephemeroptera: Heptageniidae).
    BMC evolutionary biology, 2016
    Co-Authors: Laurent Vuataz, Michael T. Monaghan, Sereina Rutschmann, Michel Sartori
    Abstract:

    Larvae of the Holarctic mayfly genus Rhithrogena Eaton, 1881 (Ephemeroptera, Heptageniidae) are a diverse and abundant member of stream and river communities and are routinely used as bio-indicators of water quality. Rhithrogena is well diversified in the European Alps, with a number of locally endemic species, and several cryptic species have been recently detected. While several informal species groups are morphologically well defined, a lack of reliable characters for species identification considerably hampers their study. Their relationships, origin, timing of speciation and mechanisms promoting their diversification in the Alps are unknown. Here we present a species-level phylogeny of Rhithrogena in Europe using two mitochondrial and three nuclear gene regions. To improve sampling in a genus with many cryptic species, individuals were selected for analysis according to a recent DNA-based taxonomy rather than traditional nomenclature. A coalescent-based species tree and a reconstruction based on a supermatrix approach supported five of the species groups as monophyletic. A molecular clock, mapped on the most resolved phylogeny and calibrated using published mitochondrial evolution rates for insects, suggested an origin of Alpine Rhithrogena in the Oligocene/Miocene boundary. A diversification analysis that included simulation of missing species indicated a constant speciation rate over time, rather than any pronounced periods of rapid speciation. Ancestral state reconstructions provided evidence for downstream diversification in at least two species groups. Our species-level analyses of five gene regions provide clearer definitions of species groups within European Rhithrogena. A constant speciation rate over time suggests that the paleoclimatic fluctuations, including the Pleistocene glaciations, did not significantly influence the tempo of diversification of Alpine species. A downstream diversification trend in the hybrida and alpestris species groups supports a previously proposed headwater origin hypothesis for aquatic insects.

  • MT: Toward a DNA taxonomy of alpine Rhithrogena (Ephemeroptera: Heptageniidae) using a mixed Yulecoalescent analysis of mitochondrial and nuclear DNA. PLoS One 2011
    2013
    Co-Authors: Laurent Vuataz, Michel Sartori, André Wagner, Michael T. Monaghan
    Abstract:

    Aquatic larvae of many Rhithrogena mayflies (Ephemeroptera) inhabit sensitive Alpine environments. A number of species are on the IUCN Red List and many recognized species have restricted distributions and are of conservation interest. Despite their ecological and conservation importance, ambiguous morphological differences among closely related species suggest that the current taxonomy may not accurately reflect the evolutionary diversity of the group. Here we examined the species status of nearly 50 % of European Rhithrogena diversity using a widespread sampling scheme of Alpine species that included 22 type localities, general mixed Yule-coalescent (GMYC) model analysis of one standard mtDNA marker and one newly developed nDNA marker, and morphological identification where possible. Using sequences from 533 individuals from 144 sampling localities, we observed significant clustering of the mitochondrial (cox1) marker into 31 GMYC species. Twenty-one of these could be identified based on the presence of topotypes (expertly identified specimens from the species ’ type locality) or unambiguous morphology. These results strongly suggest the presence of both cryptic diversity and taxonomic oversplitting in Rhithrogena. Significant clustering was not detected with protein-coding nuclear PEPCK, although nine GMYC species were congruent with well supported terminal clusters of nDNA. Lack of greater congruence in the two data sets may be the result of incomplete sorting of ancestral polymorphism. Bayesian phylogenetic analyses of both gene regions recovered four of the six recognized Rhithrogena species groups in our samples as monophyletic. Futur

  • Bayesian majority-rule consensus tree of the reduced PEPCK data set obtained using MrBayes.
    2013
    Co-Authors: Laurent Vuataz, Michel Sartori, André Wagner, Michael T. Monaghan
    Abstract:

    Lineages 1 to 4 correspond to four different Rhithrogena morphological species groups (1: alpestris; 2: loyolaea; 3: diaphana; 4: semicolorata). Lineage 5 includes clades belonging to the hercynia species group (arrows) and the hybrida species group. Triangles represent collapsed lineages, (width proportional to the number of haplotypes). Filled stars indicate posterior probabilities (PP)>0.95, open stars indicate PP>0.75.

  • Bayesian majority-rule consensus tree of the reduced cox1 data set obtained using MrBayes.
    2013
    Co-Authors: Laurent Vuataz, Michel Sartori, André Wagner, Michael T. Monaghan
    Abstract:

    Lineages 1 to 4 correspond to four different Rhithrogena morphological species groups (1: alpestris; 2: loyolaea; 3: diaphana; 4: semicolorata). Lineage 5 includes clades belonging to the hercynia species group (arrows) and the hybrida species group. Triangles represent collapsed lineages, (width proportional to the number of haplotypes). Filled stars indicate posterior probabilities (PP)>0.95, open stars indicate PP>0.75.

  • Toward a DNA Taxonomy of Alpine Rhithrogena (Ephemeroptera: Heptageniidae) Using a Mixed Yule-Coalescent Analysis of Mitochondrial and Nuclear DNA
    PloS one, 2011
    Co-Authors: Laurent Vuataz, Michel Sartori, André Wagner, Michael T. Monaghan
    Abstract:

    Aquatic larvae of many Rhithrogena mayflies (Ephemeroptera) inhabit sensitive Alpine environments. A number of species are on the IUCN Red List and many recognized species have restricted distributions and are of conservation interest. Despite their ecological and conservation importance, ambiguous morphological differences among closely related species suggest that the current taxonomy may not accurately reflect the evolutionary diversity of the group. Here we examined the species status of nearly 50% of European Rhithrogena diversity using a widespread sampling scheme of Alpine species that included 22 type localities, general mixed Yule-coalescent (GMYC) model analysis of one standard mtDNA marker and one newly developed nDNA marker, and morphological identification where possible. Using sequences from 533 individuals from 144 sampling localities, we observed significant clustering of the mitochondrial (cox1) marker into 31 GMYC species. Twenty-one of these could be identified based on the presence of topotypes (expertly identified specimens from the species' type locality) or unambiguous morphology. These results strongly suggest the presence of both cryptic diversity and taxonomic oversplitting in Rhithrogena. Significant clustering was not detected with protein-coding nuclear PEPCK, although nine GMYC species were congruent with well supported terminal clusters of nDNA. Lack of greater congruence in the two data sets may be the result of incomplete sorting of ancestral polymorphism. Bayesian phylogenetic analyses of both gene regions recovered four of the six recognized Rhithrogena species groups in our samples as monophyletic. Future development of more nuclear markers would facilitate multi-locus analysis of unresolved, closely related species pairs. The DNA taxonomy developed here lays the groundwork for a future revision of the important but cryptic Rhithrogena genus in Europe.