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Rolf G. Beutel - One of the best experts on this subject based on the ideXlab platform.
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Phylogenetic methods applied to extinct beetles — the case of † Tunguskagyrus (Gyrinidae or †Triaplidae)
Palaeoentomology, 2019Co-Authors: Rolf G. Beutel, Evgeny V. Yan, John F. LawrenceAbstract:†Tunguskagyrus, a Late Permian beetle fossil, was assigned to the Adephagan family Gyrinidae in the original description. This placement was challenged in a recent study, where the genus was considered as part of a broad new concept of the extinct family †Triaplidae and transferred from Adephaga to Archostemata. Even though some structural features deviate from the typical pattern found in extant Gyrinidae, we maintain the placement of †Tunguskagyrus in the stemgroup of this family as the most plausibe interpretation. The suggested taxonomic changes concerning †Triaplidae (and †Schizophoroidea) are invalidated by an insufficient phylogenetic approach and several misinterpretations of the fossil imprints. The arguments are based on 1) general habitual similarity, 2) ubiquitous characters, 3) plesiomorphies, or 4) apomorphic conditions (compared to the Coleopteran groundplan) occurring in many beetle groups, strongly affected by homoplasy. The taxonomic shift of †Tunguskagyrus and the new concept of †Schizophoroidea and †Triaplidae are discarded due to the lack of a defined phylogenetic methodology and synapomorphies.
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whirling in the late permian ancestral gyrinidae show early radiation of beetles before permian triassic mass extinction
BMC Evolutionary Biology, 2018Co-Authors: Rolf G. Beutel, Evgeny V. Yan, John F. LawrenceAbstract:Gyrinidae are a charismatic group of highly specialized beetles, adapted for a unique lifestyle of swimming on the water surface. They prey on drowning insects and other small arthropods caught in the surface film. Studies based on morphological and molecular data suggest that gyrinids were the first branch splitting off in Adephaga, the second largest suborder of beetles. Despite its basal position within this lineage and a very peculiar morphology, earliest Gyrinidae were recorded not earlier than from the Upper Triassic. Tunguskagyrus. with the single species Tunguskagyrus planus is described from Late Permian deposits of the Anakit area in Middle Siberia. The genus is assigned to the stemgroup of Gyrinidae, thus shifting back the minimum age of this taxon considerably: Tunguskagyrus demonstrates 250 million years of evolutionary stability for a very specialized lifestyle, with a number of key apomorphies characteristic for these epineuston predators and scavengers, but also with some preserved ancestral features not found in extant members of the family. It also implies that major splitting events in this suborder and in crown group Coleoptera had already occurred in the Permian. Gyrinidae and especially aquatic groups of Dytiscoidea flourished in the Mesozoic (for example Coptoclavidae and Dytiscidae) and most survive until the present day, despite the dramatic “Great Dying” – Permian-Triassic mass extinction, which took place shortly (in geological terms) after the time when Tunguskagyrus lived. Tunguskagyrus confirms a Permian origin of Adephaga, which was recently suggested by phylogenetic “tip-dating” analysis including both fossil and Recent gyrinids. This also confirms that main splitting events leading to the “modern” lineages of beetles took place before the Permian-Triassic mass extinction. Tunguskagyrus shows that Gyrinidae became adapted to swimming on the water surface long before Mesozoic invasions of the aquatic environment took place (Dytiscoidea). The Permian origin of Gyrinidae is consistent with a placement of this highly derived family as the sister group of all remaining Adephagan groups, as suggested based on morphological features of larvae and adults and recent analyses of molecular data.
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Whirling in the late Permian: ancestral Gyrinidae show early radiation of beetles before Permian-Triassic mass extinction
BMC, 2018Co-Authors: Evgeny V. Yan, Rolf G. Beutel, John F. LawrenceAbstract:Abstract Background Gyrinidae are a charismatic group of highly specialized beetles, adapted for a unique lifestyle of swimming on the water surface. They prey on drowning insects and other small arthropods caught in the surface film. Studies based on morphological and molecular data suggest that gyrinids were the first branch splitting off in Adephaga, the second largest suborder of beetles. Despite its basal position within this lineage and a very peculiar morphology, earliest Gyrinidae were recorded not earlier than from the Upper Triassic. Results Tunguskagyrus. with the single species Tunguskagyrus planus is described from Late Permian deposits of the Anakit area in Middle Siberia. The genus is assigned to the stemgroup of Gyrinidae, thus shifting back the minimum age of this taxon considerably: Tunguskagyrus demonstrates 250 million years of evolutionary stability for a very specialized lifestyle, with a number of key apomorphies characteristic for these epineuston predators and scavengers, but also with some preserved ancestral features not found in extant members of the family. It also implies that major splitting events in this suborder and in crown group Coleoptera had already occurred in the Permian. Gyrinidae and especially aquatic groups of Dytiscoidea flourished in the Mesozoic (for example Coptoclavidae and Dytiscidae) and most survive until the present day, despite the dramatic “Great Dying” – Permian-Triassic mass extinction, which took place shortly (in geological terms) after the time when Tunguskagyrus lived. Conclusions Tunguskagyrus confirms a Permian origin of Adephaga, which was recently suggested by phylogenetic “tip-dating” analysis including both fossil and Recent gyrinids. This also confirms that main splitting events leading to the “modern” lineages of beetles took place before the Permian-Triassic mass extinction. Tunguskagyrus shows that Gyrinidae became adapted to swimming on the water surface long before Mesozoic invasions of the aquatic environment took place (Dytiscoidea). The Permian origin of Gyrinidae is consistent with a placement of this highly derived family as the sister group of all remaining Adephagan groups, as suggested based on morphological features of larvae and adults and recent analyses of molecular data
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On the phylogeny and evolution of Mesozoic and extant lineages of Adephaga (Coleoptera, Insecta)
Cladistics, 2012Co-Authors: Rolf G. Beutel, Jingjing Tan, Dong Ren, Bo Wang, Xing-ke YangAbstract:The relationships of extant and extinct lineages of Adephaga were analysed formally for the first time. Emphasis is placed on the aquatic and semiaquatic groups and their evolution in the Mesozoic. †Triadogyrus and †Mesodineutus belong to Gyrinidae, the sister group of the remaining families. †Triaplidae are the sister group of the following groups (Haliplidae, GeAdephaga, Dytiscoidea incl. †Liadytidae, †Parahygrobiidae and †Coptoclavidae [major part]). The lack of a ventral procoxal joint and a very short prosternal process are plesiomorphies of †Triaplidae. †Coptoclavidae and †Timarchopsinae are paraphyletic. †Timarchopsis is placed in a geAdephagan clade. In contrast to other coptoclavids, its metathorax is close to the condition found in Haliplidae, with a complete transverse ridge and coxae with large plates and free mesal walls. †Coptoclavidae s.str., i.e. excl. †Timarchopsis, is a dytiscoid subgroup. The mesal metacoxal walls are fused, the coxal plates are reduced, and the transverse ridge is absent. †Stygeonectes belongs to this dytiscoid coptoclavid unit and is therefore misplaced in †Timarchopsinae. †Liadytidae belongs to a dytiscoid subgroup, which also comprises the extant families Aspidytidae, Amphizoidae, Hygrobiidae and Dytiscidae. †Parahygrobia is the sister group of Hygrobiidae. The larvae are characterized by a broad gula, the absence of the lacinia, retractile maxillary bases and very long urogomphi set with long setae. †Liadytiscinae is the sister group of extant Dytiscidae. There is no support for a clade †Eodromeinae and for Trachypachidae incl. †Eodromeinae. †Fortiseode is nested within Carabidae. The exclusion of fossil taxa has no effect on the branching pattern. The evolution of Adephaga in the Mesozoic is discussed. Possible reasons for the extinction of †Coptoclavidae are the rise of teleost fish and the competition of Gyrinidae and Dytiscidae, which possess efficient defensive glands and larval mandibular sucking channels.
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is meru a specialized noterid coleoptera Adephaga
Systematic Entomology, 2011Co-Authors: Carina Dressler, Rolf G. BeutelAbstract:Larval characters of Meru were extracted from the recently published description and added to an extensive data matrix from an earlier study on the phylogenetic position of the genus and family. The results confirm the earlier postulated clade Meruidae + Noteridae with strong support. The larvae share several characteristics with noterid larvae, notably the specific head shape, with the greatest width close to the foramen occipitale, the fissure-shaped posterior tentorial grooves at the posterior margin of the head capsule and the anteriorly cleft prementum. From a formal point of view, it would be justified to treat Meru as a subgroup of Noteridae (if the larva is properly identified). We refute the placement of Meruidae as a sister group of the remaining Dytiscoidea (including Noteridae). The new larval characters are valuable and informative, but a small set of external features is not sufficient for a reliable placement of Meruidae.
John F. Lawrence - One of the best experts on this subject based on the ideXlab platform.
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Phylogenetic methods applied to extinct beetles — the case of † Tunguskagyrus (Gyrinidae or †Triaplidae)
Palaeoentomology, 2019Co-Authors: Rolf G. Beutel, Evgeny V. Yan, John F. LawrenceAbstract:†Tunguskagyrus, a Late Permian beetle fossil, was assigned to the Adephagan family Gyrinidae in the original description. This placement was challenged in a recent study, where the genus was considered as part of a broad new concept of the extinct family †Triaplidae and transferred from Adephaga to Archostemata. Even though some structural features deviate from the typical pattern found in extant Gyrinidae, we maintain the placement of †Tunguskagyrus in the stemgroup of this family as the most plausibe interpretation. The suggested taxonomic changes concerning †Triaplidae (and †Schizophoroidea) are invalidated by an insufficient phylogenetic approach and several misinterpretations of the fossil imprints. The arguments are based on 1) general habitual similarity, 2) ubiquitous characters, 3) plesiomorphies, or 4) apomorphic conditions (compared to the Coleopteran groundplan) occurring in many beetle groups, strongly affected by homoplasy. The taxonomic shift of †Tunguskagyrus and the new concept of †Schizophoroidea and †Triaplidae are discarded due to the lack of a defined phylogenetic methodology and synapomorphies.
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Australian Beetles Volume 2: Archostemata, Myxophaga, Adephaga, Polyphaga (part)
2019Co-Authors: Adam Ślipiński, John F. LawrenceAbstract:This three-volume series represents a comprehensive treatment of the beetles of Australia, a relatively under-studied fauna that includes many unusual and unique lineages found nowhere else on Earth. Volume 2 contains 36 chapters, providing critical information and identification keys to the genera of the Australian beetle families included in suborders Archostemata, Myxophaga, Adephaga and several groups of Polyphaga (Scirtoidea, Hydrophiloidea, Scarabaeoidea, Buprestoidea and Tenebrionidae). Each chapter is richly illustrated in black and white drawings and photographs. The book also includes colour habitus figures for about 1000 Australian beetle genera and subgenera belonging to the families treated in this volume. This volume is a truly international collaborative effort, as the chapters have been written by 23 contributors from Australia, China, Czech Republic, Germany, Italy, Poland and USA.
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whirling in the late permian ancestral gyrinidae show early radiation of beetles before permian triassic mass extinction
BMC Evolutionary Biology, 2018Co-Authors: Rolf G. Beutel, Evgeny V. Yan, John F. LawrenceAbstract:Gyrinidae are a charismatic group of highly specialized beetles, adapted for a unique lifestyle of swimming on the water surface. They prey on drowning insects and other small arthropods caught in the surface film. Studies based on morphological and molecular data suggest that gyrinids were the first branch splitting off in Adephaga, the second largest suborder of beetles. Despite its basal position within this lineage and a very peculiar morphology, earliest Gyrinidae were recorded not earlier than from the Upper Triassic. Tunguskagyrus. with the single species Tunguskagyrus planus is described from Late Permian deposits of the Anakit area in Middle Siberia. The genus is assigned to the stemgroup of Gyrinidae, thus shifting back the minimum age of this taxon considerably: Tunguskagyrus demonstrates 250 million years of evolutionary stability for a very specialized lifestyle, with a number of key apomorphies characteristic for these epineuston predators and scavengers, but also with some preserved ancestral features not found in extant members of the family. It also implies that major splitting events in this suborder and in crown group Coleoptera had already occurred in the Permian. Gyrinidae and especially aquatic groups of Dytiscoidea flourished in the Mesozoic (for example Coptoclavidae and Dytiscidae) and most survive until the present day, despite the dramatic “Great Dying” – Permian-Triassic mass extinction, which took place shortly (in geological terms) after the time when Tunguskagyrus lived. Tunguskagyrus confirms a Permian origin of Adephaga, which was recently suggested by phylogenetic “tip-dating” analysis including both fossil and Recent gyrinids. This also confirms that main splitting events leading to the “modern” lineages of beetles took place before the Permian-Triassic mass extinction. Tunguskagyrus shows that Gyrinidae became adapted to swimming on the water surface long before Mesozoic invasions of the aquatic environment took place (Dytiscoidea). The Permian origin of Gyrinidae is consistent with a placement of this highly derived family as the sister group of all remaining Adephagan groups, as suggested based on morphological features of larvae and adults and recent analyses of molecular data.
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Whirling in the late Permian: ancestral Gyrinidae show early radiation of beetles before Permian-Triassic mass extinction
BMC, 2018Co-Authors: Evgeny V. Yan, Rolf G. Beutel, John F. LawrenceAbstract:Abstract Background Gyrinidae are a charismatic group of highly specialized beetles, adapted for a unique lifestyle of swimming on the water surface. They prey on drowning insects and other small arthropods caught in the surface film. Studies based on morphological and molecular data suggest that gyrinids were the first branch splitting off in Adephaga, the second largest suborder of beetles. Despite its basal position within this lineage and a very peculiar morphology, earliest Gyrinidae were recorded not earlier than from the Upper Triassic. Results Tunguskagyrus. with the single species Tunguskagyrus planus is described from Late Permian deposits of the Anakit area in Middle Siberia. The genus is assigned to the stemgroup of Gyrinidae, thus shifting back the minimum age of this taxon considerably: Tunguskagyrus demonstrates 250 million years of evolutionary stability for a very specialized lifestyle, with a number of key apomorphies characteristic for these epineuston predators and scavengers, but also with some preserved ancestral features not found in extant members of the family. It also implies that major splitting events in this suborder and in crown group Coleoptera had already occurred in the Permian. Gyrinidae and especially aquatic groups of Dytiscoidea flourished in the Mesozoic (for example Coptoclavidae and Dytiscidae) and most survive until the present day, despite the dramatic “Great Dying” – Permian-Triassic mass extinction, which took place shortly (in geological terms) after the time when Tunguskagyrus lived. Conclusions Tunguskagyrus confirms a Permian origin of Adephaga, which was recently suggested by phylogenetic “tip-dating” analysis including both fossil and Recent gyrinids. This also confirms that main splitting events leading to the “modern” lineages of beetles took place before the Permian-Triassic mass extinction. Tunguskagyrus shows that Gyrinidae became adapted to swimming on the water surface long before Mesozoic invasions of the aquatic environment took place (Dytiscoidea). The Permian origin of Gyrinidae is consistent with a placement of this highly derived family as the sister group of all remaining Adephagan groups, as suggested based on morphological features of larvae and adults and recent analyses of molecular data
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EVOLUTION OF THE HIND WING IN COLEOPTERA
The Canadian Entomologist, 1993Co-Authors: Jarmila Kukalová-peck, John F. LawrenceAbstract:A survey is made of the major features of the venation, articulation, and folding in the hind wings of Coleoptera. The documentation is based upon examination of 108 Coleoptera families and 200 specimens, and shown in 101 published figures. Wing veins and articular sclerites are homologized with elements of the neopteran wing groundplan, resulting in wing vein terminology that differs substantially from that generally used by coleopterists. We tabulate the differences between currently used venational nomenclature and the all-pterygote homologous symbols. The use of the neopteran groundplan, combined with the knowledge of the way in which veins evolved, provides many strong characters linked to the early evolutionary radiation of Coleoptera. The order originated with the development of the apical folding of the hind wings under the elytra executed by the radial and medial loop. The loops, which are very complex venational structures, further diversified in four distinctly different ways which mark the highest (suborder) taxa. The remaining venation and the wing articulation have changed with the loops, which formed additional synapomorphies and autapomorphies at the suborder, superfamily, and sometimes even family and tribe levels. Relationships among the four currently recognized suborders of Coleoptera are reexamined using hind wing characters. The number of wing-related apomorphies are 16 in Coleoptera, seven in Archostemata + Adephaga–Myxophaga, four in Adephaga–Myxophaga, seven in Myxophaga, nine in Archostemata, and five in Polyphaga. The following phylogenetic scheme is suggested: Polyphaga [Archostemata (Adephaga + Myxophaga)]. Venational evidence is given to define two major lineages (the hydrophiloid and the eucinetoid) within the suborder Polyphaga. The unique apical wing folding mechanism of beetles is described. Derived types of wing folding are discussed, based mainly on a survey of recent literature. A sister group relationship between Coleoptera and Strepsiptera is supported by hind wing evidence.
Carina Dressler - One of the best experts on this subject based on the ideXlab platform.
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is meru a specialized noterid coleoptera Adephaga
Systematic Entomology, 2011Co-Authors: Carina Dressler, Rolf G. BeutelAbstract:Larval characters of Meru were extracted from the recently published description and added to an extensive data matrix from an earlier study on the phylogenetic position of the genus and family. The results confirm the earlier postulated clade Meruidae + Noteridae with strong support. The larvae share several characteristics with noterid larvae, notably the specific head shape, with the greatest width close to the foramen occipitale, the fissure-shaped posterior tentorial grooves at the posterior margin of the head capsule and the anteriorly cleft prementum. From a formal point of view, it would be justified to treat Meru as a subgroup of Noteridae (if the larva is properly identified). We refute the placement of Meruidae as a sister group of the remaining Dytiscoidea (including Noteridae). The new larval characters are valuable and informative, but a small set of external features is not sufficient for a reliable placement of Meruidae.
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Is Meru a specialized noterid (Coleoptera, Adephaga)?
Systematic Entomology, 2011Co-Authors: Carina Dressler, Rolf G. BeutelAbstract:Larval characters of Meru were extracted from the recently published description and added to an extensive data matrix from an earlier study on the phylogenetic position of the genus and family. The results confirm the earlier postulated clade Meruidae + Noteridae with strong support. The larvae share several characteristics with noterid larvae, notably the specific head shape, with the greatest width close to the foramen occipitale, the fissure-shaped posterior tentorial grooves at the posterior margin of the head capsule and the anteriorly cleft prementum. From a formal point of view, it would be justified to treat Meru as a subgroup of Noteridae (if the larva is properly identified). We refute the placement of Meruidae as a sister group of the remaining Dytiscoidea (including Noteridae). The new larval characters are valuable and informative, but a small set of external features is not sufficient for a reliable placement of Meruidae.
Evgeny V. Yan - One of the best experts on this subject based on the ideXlab platform.
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Phylogenetic methods applied to extinct beetles — the case of † Tunguskagyrus (Gyrinidae or †Triaplidae)
Palaeoentomology, 2019Co-Authors: Rolf G. Beutel, Evgeny V. Yan, John F. LawrenceAbstract:†Tunguskagyrus, a Late Permian beetle fossil, was assigned to the Adephagan family Gyrinidae in the original description. This placement was challenged in a recent study, where the genus was considered as part of a broad new concept of the extinct family †Triaplidae and transferred from Adephaga to Archostemata. Even though some structural features deviate from the typical pattern found in extant Gyrinidae, we maintain the placement of †Tunguskagyrus in the stemgroup of this family as the most plausibe interpretation. The suggested taxonomic changes concerning †Triaplidae (and †Schizophoroidea) are invalidated by an insufficient phylogenetic approach and several misinterpretations of the fossil imprints. The arguments are based on 1) general habitual similarity, 2) ubiquitous characters, 3) plesiomorphies, or 4) apomorphic conditions (compared to the Coleopteran groundplan) occurring in many beetle groups, strongly affected by homoplasy. The taxonomic shift of †Tunguskagyrus and the new concept of †Schizophoroidea and †Triaplidae are discarded due to the lack of a defined phylogenetic methodology and synapomorphies.
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whirling in the late permian ancestral gyrinidae show early radiation of beetles before permian triassic mass extinction
BMC Evolutionary Biology, 2018Co-Authors: Rolf G. Beutel, Evgeny V. Yan, John F. LawrenceAbstract:Gyrinidae are a charismatic group of highly specialized beetles, adapted for a unique lifestyle of swimming on the water surface. They prey on drowning insects and other small arthropods caught in the surface film. Studies based on morphological and molecular data suggest that gyrinids were the first branch splitting off in Adephaga, the second largest suborder of beetles. Despite its basal position within this lineage and a very peculiar morphology, earliest Gyrinidae were recorded not earlier than from the Upper Triassic. Tunguskagyrus. with the single species Tunguskagyrus planus is described from Late Permian deposits of the Anakit area in Middle Siberia. The genus is assigned to the stemgroup of Gyrinidae, thus shifting back the minimum age of this taxon considerably: Tunguskagyrus demonstrates 250 million years of evolutionary stability for a very specialized lifestyle, with a number of key apomorphies characteristic for these epineuston predators and scavengers, but also with some preserved ancestral features not found in extant members of the family. It also implies that major splitting events in this suborder and in crown group Coleoptera had already occurred in the Permian. Gyrinidae and especially aquatic groups of Dytiscoidea flourished in the Mesozoic (for example Coptoclavidae and Dytiscidae) and most survive until the present day, despite the dramatic “Great Dying” – Permian-Triassic mass extinction, which took place shortly (in geological terms) after the time when Tunguskagyrus lived. Tunguskagyrus confirms a Permian origin of Adephaga, which was recently suggested by phylogenetic “tip-dating” analysis including both fossil and Recent gyrinids. This also confirms that main splitting events leading to the “modern” lineages of beetles took place before the Permian-Triassic mass extinction. Tunguskagyrus shows that Gyrinidae became adapted to swimming on the water surface long before Mesozoic invasions of the aquatic environment took place (Dytiscoidea). The Permian origin of Gyrinidae is consistent with a placement of this highly derived family as the sister group of all remaining Adephagan groups, as suggested based on morphological features of larvae and adults and recent analyses of molecular data.
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Whirling in the late Permian: ancestral Gyrinidae show early radiation of beetles before Permian-Triassic mass extinction
BMC, 2018Co-Authors: Evgeny V. Yan, Rolf G. Beutel, John F. LawrenceAbstract:Abstract Background Gyrinidae are a charismatic group of highly specialized beetles, adapted for a unique lifestyle of swimming on the water surface. They prey on drowning insects and other small arthropods caught in the surface film. Studies based on morphological and molecular data suggest that gyrinids were the first branch splitting off in Adephaga, the second largest suborder of beetles. Despite its basal position within this lineage and a very peculiar morphology, earliest Gyrinidae were recorded not earlier than from the Upper Triassic. Results Tunguskagyrus. with the single species Tunguskagyrus planus is described from Late Permian deposits of the Anakit area in Middle Siberia. The genus is assigned to the stemgroup of Gyrinidae, thus shifting back the minimum age of this taxon considerably: Tunguskagyrus demonstrates 250 million years of evolutionary stability for a very specialized lifestyle, with a number of key apomorphies characteristic for these epineuston predators and scavengers, but also with some preserved ancestral features not found in extant members of the family. It also implies that major splitting events in this suborder and in crown group Coleoptera had already occurred in the Permian. Gyrinidae and especially aquatic groups of Dytiscoidea flourished in the Mesozoic (for example Coptoclavidae and Dytiscidae) and most survive until the present day, despite the dramatic “Great Dying” – Permian-Triassic mass extinction, which took place shortly (in geological terms) after the time when Tunguskagyrus lived. Conclusions Tunguskagyrus confirms a Permian origin of Adephaga, which was recently suggested by phylogenetic “tip-dating” analysis including both fossil and Recent gyrinids. This also confirms that main splitting events leading to the “modern” lineages of beetles took place before the Permian-Triassic mass extinction. Tunguskagyrus shows that Gyrinidae became adapted to swimming on the water surface long before Mesozoic invasions of the aquatic environment took place (Dytiscoidea). The Permian origin of Gyrinidae is consistent with a placement of this highly derived family as the sister group of all remaining Adephagan groups, as suggested based on morphological features of larvae and adults and recent analyses of molecular data
Peter Hammond - One of the best experts on this subject based on the ideXlab platform.
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Sequence Alignment of 18S Ribosomal RNA and the Basal Relationships of Adephagan Beetles: Evidence for Monophyly of Aquatic Families and the Placement of Trachypachidae
Systematic biology, 2001Co-Authors: Verel L. Shull, Michael D Baker, David R Maddison, Alfried P. Vogler, Peter HammondAbstract:Current hypotheses regarding family relationships in the suborder Adephaga (Coleoptera) are conflicting. Here we report full-length 18S ribosomal RNA sequences of 39 Adephagans and 13 outgroup taxa. Data analysis focused on the impact of sequence alignment on tree topology, using two principally different approaches. Tree alignments, which seek to minimize indels and substitutions on the tree in a single step, as implemented in an approximate procedure by the computer program POY, were contrasted with a more traditional procedure based on alignments followed by phylogenetic inference based on parsimony, likelihood, and distance analyses. Despite substantial differences between the procedures, phylogenetic conclusions regarding basal relationships within Adephaga and relationships between the four suborders of Coleoptera were broadly similar. The analysis weakly supports monophyly of Adephaga, with Polyphaga usually as its sister, and the two small suborders Myxophaga and Archostemata basal to them. In some analyses, however, Polyphaga was reconstructed as having arisen from within HydrAdephaga. Adephaga generally split into two monophyletic groups, corresponding to the terrestrial GeAdephaga and the aquatic HydrAdephaga, as initially proposed by Crowson in 1955, consistent with a single colonization of the aquatic environment by Adephagan ancestors and contradicting the recent proposition of three independent invasions. A monophyletic HydrAdephaga is consistently, though not strongly, supported under most analyses, and a parametric bootstrapping test significantly rejects an hypothesis of nonmonophyly. The enigmatic Trachypachidae, which exhibit many similarities to aquatic forms but whose species are entirely terrestrial, were usually recovered as a basal lineage within GeAdephaga. Strong evidence opposes the view that terrestrial trachypachids are related to the dytiscoid water beetles.
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sequence alignment of 18s ribosomal rna and the basal relationships of Adephagan beetles evidence for monophyly of aquatic families and the placement of trachypachidae
Systematic Biology, 2001Co-Authors: Verel L. Shull, Michael D Baker, David R Maddison, Alfried P. Vogler, Peter HammondAbstract:Currenthypotheses regarding family relationshipsin the suborderAdephaga (Coleoptera) are cone icting. Here we report full-length 18S ribosomal RNA sequences of 39 Adephagans and 13 outgroup taxa. Data analysis focused on the impact of sequence alignment on tree topology, using two principally different approaches. Tree alignments, which seek to minimize indels and substi- tutions on the tree in a single step, as implemented in an approximate procedure by the computer program POY, were contrasted with a more traditional procedure based on alignments followed by phylogenetic inference based on parsimony, likelihood, and distance analyses. Despite substantial differences between the procedures, phylogenetic conclusions regarding basal relationships within Adephaga and relationships between the four suborders of Coleoptera were broadly similar. The analysis weakly supports monophyly of Adephaga, with Polyphaga usually as its sister, and the two small suborders Myxophaga and Archostemata basalto them. In some analyses, however, Polyphaga was reconstructed as having arisen from within HydrAdephaga. Adephaga generally split into two monophyletic groups, corresponding to the terrestrial GeAdephaga and the aquatic HydrAdephaga, as initially proposed by Crowson in 1955, consistent with a single colonization of the aquatic en- vironment by Adephagan ancestors and contradicting the recent proposition of three independent invasions. AmonophyleticHydrAdephaga isconsistently,though not strongly,supported undermost analyses, and a parametric bootstrapping test signie cantly rejects an hypothesis of nonmonophyly. The enigmatic Trachypachidae, which exhibit many similarities to aquatic forms but whose species are entirely terrestrial, were usually recovered as a basallineage within GeAdephaga. Strong evidence opposes the view that terrestrial trachypachids are related to the dytiscoid water beetles. (Adephaga; aquatic beetles; Coleoptera; sequence alignment; small subunit rRNA, tree alignment.)