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Hojun Song - One of the best experts on this subject based on the ideXlab platform.
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300 million years of diversification elucidating the patterns of orthopteran evolution based on comprehensive taxon and gene sampling
Cladistics, 2015Co-Authors: Christiane Amedegnato, Maria Marta Cigliano, Laure Desuttergrandcolas, Sam William Heads, Daniel Otte, Hojun Song, Yuanyuan Huang, Michael F. WhitingAbstract:Orthoptera is the most diverse order among the polyneopteran groups and includes familiar insects, such as grasshoppers, crickets, katydids, and their kin. Due to a long history of conflicting classification schemes based on different interpretations of morphological characters, the phylogenetic relationships within Orthoptera are poorly understood and its higher classification has remained unstable. In this study, we establish a robust phylogeny of Orthoptera including 36 of 40 families representing all 15 currently recognized superfamilies and based on complete mitochondrial genomes and four nuclear loci, in order to test previous phylogenetic hypotheses and to provide a framework for a natural classification and a reference for studying the pattern of divergence and diversification. We find strong support for monophyletic suborders (Ensifera and Caelifera) as well as major superfamilies. Our results corroborate most of the higher-level relationships previously proposed for Caelifera, but suggest some novel relationships for Ensifera. Using fossil calibrations, we provide divergence time estimates for major orthopteran lineages and show that the current diversity has been shaped by dynamic shifts of diversification rates at different geological times across different lineages. We also show that mitochondrial tRNA gene orders have been relatively stable throughout the evolutionary history of Orthoptera, but a major tRNA gene rearrangement occurred in the common ancestor of Tetrigoidea and Acridomorpha, thereby representing a robust molecular synapomorphy, which has persisted for 250 Myr. © The Willi Hennig Society 2015.
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searching for the optimal data partitioning strategy in mitochondrial phylogenomics a phylogeny of acridoidea insecta orthoptera Caelifera as a case study
Molecular Phylogenetics and Evolution, 2013Co-Authors: James R Leavitt, Hojun Song, Michael F. Whiting, Kevin D HiattAbstract:One of the main challenges in analyzing multi-locus phylogenomic data is to find an optimal data partitioning strategy to account for variable evolutionary histories of different loci for any given dataset. Although a number of studies have addressed the issue of data partitioning in a Bayesian phylogenetic framework, such studies in a maximum likelihood framework are comparatively lacking. Furthermore, a rigorous statistical exploration of possible data partitioning schemes has not been applied to mitochondrial genome (mtgenome) data, which provide a complex, but manageable platform for addressing various challenges in analyzing phylogenomic data. In this study, we investigate the issue of data partitioning in the maximum likelihood framework in the context of the mitochondrial phylogenomics of an orthopteran superfamily Acridoidea (Orthoptera: Caelifera). The present study analyzes 34 terminals representing all 8 superfamilies within Caelifera, which includes newly sequenced partial or complete mtgenomes for 11 families. Using a new partition-selection method implemented in the software PartitionFinder, we compare a large number of data partitioning schemes in an attempt to identify the most effective method of analyzing the mtgenome data. We find that the best-fit partitioning scheme selected by PartitionFinder is superior to any a priori schemes commonly utilized in mitochondrial phylogenomics. We also show that over-partitioning is often detrimental to phylogenetic reconstruction. A comparative analysis of mtgenome structures finds that the tRNA gene rearrangement between cytochrome c oxidase subunit II and ATP synthase protein 8 does not occur in the most basal Caeliferan lineage Tridactyloidea, suggesting that this gene rearrangement must have evolved at least in the common ancestor of Tetrigoidea and Acridomorpha. We find that mtgenome data contain sufficient phylogenetic information to broadly resolve the relationships across Acridomorpha and Acridoidea.
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grasshopper systematics past present and future
Journal of Orthoptera Research, 2010Co-Authors: Hojun SongAbstract:Abstract For the past 250 y, tremendous advances have been made in the field of grasshopper systematics. There have been several breakthroughs that have pushed the field forward, and behind these breakthroughs were numerous visionary taxonomists. This article is a celebration of those taxonomists and their achievements. In this review, I provide a general overview of the field and describe major advances that have shaped our understanding of grasshopper systematics. Specifically, I review the pattern of species description in Acridomorpha (Orthoptera: Caelifera) since Linnaeus, and highlight the achievements of important taxonomists. Finally, I end with some of the problems that we grasshopper taxonomists are facing today and challenge the field as a whole to move forward.
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A preliminary mitochondrial genome phylogeny of Orthoptera (Insecta) and approaches to maximizing phylogenetic signal found within mitochondrial genome data.
Molecular phylogenetics and evolution, 2008Co-Authors: J. Daniel Fenn, Hojun Song, Stephen L. Cameron, Michael F. WhitingAbstract:The phylogenetic utility of mitochondrial genomes (mtgenomes) is examined using the framework of a preliminary phylogeny of Orthoptera. This study presents five newly sequenced genomes from four orthopteran families. While all ensiferan and polyneopteran taxa retain the ancestral gene order, all Caeliferan lineages including the newly sequenced Caeliferan species contain a tRNA rearrangement from the insect ground plan tRNA(Lys)(K)-tRNA(Asp)(D) swapping to tRNA(Asp) (D)-tRNA(Lys) (K) confirming that this rearrangement is a possible molecular synapomorphy for this suborder. The phylogenetic signal in mtgenomes is rigorously examined under the analytical regimens of parsimony, maximum likelihood and Bayesian inference, along with how gene inclusion/exclusion, data recoding, gap coding, and different partitioning schemes influence the phylogenetic reconstruction. When all available data are analyzed simultaneously, the monophyly of Orthoptera and its two suborders, Caelifera and Ensifera, are consistently recovered in the context of our taxon sampling, regardless of the optimality criteria. When protein-coding genes are analyzed as a single partition, nearly identical topology to the combined analyses is recovered, suggesting that much of the signals of the mtgenome come from the protein-coding genes. Transfer and ribosomal RNAs perform poorly when analyzed individually, but contribute signal when analyzed in combination with the protein-coding genes. Inclusion of third codon position of the protein-coding genes does not negatively affect the phylogenetic reconstruction when all genes are analyzed together, whereas recoding of the protein-coding genes into amino acid sequences introduces artificial resolution. Over-partitioning in a Bayesian framework appears to have a negative effect in achieving convergence. Our findings suggest that the best phylogenetic inferences are made when all available nucleotide data from the mtgenome are analyzed simultaneously, and that the mtgenome data can resolve over a wide time scale from the Permian (approximately 260 MYA) to the Tertiary (approximately 50 MYA).
Balkisu Abdulrahman - One of the best experts on this subject based on the ideXlab platform.
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growth performance and haematological characteristics of weanling wistar rats fed Caelifera supplemented diets
FUDMA JOURNAL OF SCIENCES - ISSN: 2616-1370, 2018Co-Authors: Ayuba Sullubawa Zaraddeen, Ali Siddiq Idoko, Balkisu AbdulrahmanAbstract:This research was conducted to determine the growth performance and haematological status of rats fed with Caelifera- supplemented weaning diets. Twenty four (24) weanling albino rats with mean weight of 39.27g ± 0.3g were divided into four (4) groups of equal average weight and randomly assigned to four experimental diets. Diet C (control) was Nestle wheat Cerelac. Diet A contained Rheum australe (45%), Caelifera (12.5%) Daucus carota (10%), Glycine max (30%), and sucrose (2.5%) while diets W and M respectively contained Triticum aestivum and P ennisetum glaucum instead of Rheum austral. The rats were fed ad libitum for six weeks. Proximate compositions of the diets, growth and haematological parameters were determined using standard methods. The results revealed that ash content of Diet A (0.630 ± 0.04), Diet W (0.287±0.01), and Diet M (0.490 ± 0.03) were significantly (p 0.05) variations in the average weekly feed intake, the rats fed test diets had significantly (p<0.05) higher feed conversion ratio and lower average weekly weight gain. The rats fed with the test diets had significantly (p<0.05) lower PCV, Hb and MCHC concentrations. It could be drawn from the findings that the diets, even when supplemented with Caelifera may not be as good as Nestle Cerelac. It is therefore recommended that the test diets be fortified with minerals in order to raise their nutritional status.
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GROWTH PERFORMANCE AND HAEMATOLOGICAL CHARACTERISTICS OF WEANLING WISTAR RATS FED Caelifera SUPPLEMENTED DIETS
2018Co-Authors: Ayuba Sullubawa Zaraddeen, Ali Siddiq Idoko, Balkisu AbdulrahmanAbstract:This research was conducted to determine the growth performance and haematological status of rats fed with Caelifera- supplemented weaning diets. Twenty four (24) weanling albino rats with mean weight of 39.27g ± 0.3g were divided into four (4) groups of equal average weight and randomly assigned to four experimental diets. Diet C (control) was Nestle wheat Cerelac. Diet A contained Rheum australe (45%), Caelifera (12.5%) Daucus carota (10%), Glycine max (30%), and sucrose (2.5%) while diets W and M respectively contained Triticum aestivum and P ennisetum glaucum instead of Rheum austral. The rats were fed ad libitum for six weeks. Proximate compositions of the diets, growth and haematological parameters were determined using standard methods. The results revealed that ash content of Diet A (0.630 ± 0.04), Diet W (0.287±0.01), and Diet M (0.490 ± 0.03) were significantly (p 0.05) variations in the average weekly feed intake, the rats fed test diets had significantly (p
Michael F. Whiting - One of the best experts on this subject based on the ideXlab platform.
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300 million years of diversification elucidating the patterns of orthopteran evolution based on comprehensive taxon and gene sampling
Cladistics, 2015Co-Authors: Christiane Amedegnato, Maria Marta Cigliano, Laure Desuttergrandcolas, Sam William Heads, Daniel Otte, Hojun Song, Yuanyuan Huang, Michael F. WhitingAbstract:Orthoptera is the most diverse order among the polyneopteran groups and includes familiar insects, such as grasshoppers, crickets, katydids, and their kin. Due to a long history of conflicting classification schemes based on different interpretations of morphological characters, the phylogenetic relationships within Orthoptera are poorly understood and its higher classification has remained unstable. In this study, we establish a robust phylogeny of Orthoptera including 36 of 40 families representing all 15 currently recognized superfamilies and based on complete mitochondrial genomes and four nuclear loci, in order to test previous phylogenetic hypotheses and to provide a framework for a natural classification and a reference for studying the pattern of divergence and diversification. We find strong support for monophyletic suborders (Ensifera and Caelifera) as well as major superfamilies. Our results corroborate most of the higher-level relationships previously proposed for Caelifera, but suggest some novel relationships for Ensifera. Using fossil calibrations, we provide divergence time estimates for major orthopteran lineages and show that the current diversity has been shaped by dynamic shifts of diversification rates at different geological times across different lineages. We also show that mitochondrial tRNA gene orders have been relatively stable throughout the evolutionary history of Orthoptera, but a major tRNA gene rearrangement occurred in the common ancestor of Tetrigoidea and Acridomorpha, thereby representing a robust molecular synapomorphy, which has persisted for 250 Myr. © The Willi Hennig Society 2015.
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searching for the optimal data partitioning strategy in mitochondrial phylogenomics a phylogeny of acridoidea insecta orthoptera Caelifera as a case study
Molecular Phylogenetics and Evolution, 2013Co-Authors: James R Leavitt, Hojun Song, Michael F. Whiting, Kevin D HiattAbstract:One of the main challenges in analyzing multi-locus phylogenomic data is to find an optimal data partitioning strategy to account for variable evolutionary histories of different loci for any given dataset. Although a number of studies have addressed the issue of data partitioning in a Bayesian phylogenetic framework, such studies in a maximum likelihood framework are comparatively lacking. Furthermore, a rigorous statistical exploration of possible data partitioning schemes has not been applied to mitochondrial genome (mtgenome) data, which provide a complex, but manageable platform for addressing various challenges in analyzing phylogenomic data. In this study, we investigate the issue of data partitioning in the maximum likelihood framework in the context of the mitochondrial phylogenomics of an orthopteran superfamily Acridoidea (Orthoptera: Caelifera). The present study analyzes 34 terminals representing all 8 superfamilies within Caelifera, which includes newly sequenced partial or complete mtgenomes for 11 families. Using a new partition-selection method implemented in the software PartitionFinder, we compare a large number of data partitioning schemes in an attempt to identify the most effective method of analyzing the mtgenome data. We find that the best-fit partitioning scheme selected by PartitionFinder is superior to any a priori schemes commonly utilized in mitochondrial phylogenomics. We also show that over-partitioning is often detrimental to phylogenetic reconstruction. A comparative analysis of mtgenome structures finds that the tRNA gene rearrangement between cytochrome c oxidase subunit II and ATP synthase protein 8 does not occur in the most basal Caeliferan lineage Tridactyloidea, suggesting that this gene rearrangement must have evolved at least in the common ancestor of Tetrigoidea and Acridomorpha. We find that mtgenome data contain sufficient phylogenetic information to broadly resolve the relationships across Acridomorpha and Acridoidea.
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A preliminary mitochondrial genome phylogeny of Orthoptera (Insecta) and approaches to maximizing phylogenetic signal found within mitochondrial genome data.
Molecular phylogenetics and evolution, 2008Co-Authors: J. Daniel Fenn, Hojun Song, Stephen L. Cameron, Michael F. WhitingAbstract:The phylogenetic utility of mitochondrial genomes (mtgenomes) is examined using the framework of a preliminary phylogeny of Orthoptera. This study presents five newly sequenced genomes from four orthopteran families. While all ensiferan and polyneopteran taxa retain the ancestral gene order, all Caeliferan lineages including the newly sequenced Caeliferan species contain a tRNA rearrangement from the insect ground plan tRNA(Lys)(K)-tRNA(Asp)(D) swapping to tRNA(Asp) (D)-tRNA(Lys) (K) confirming that this rearrangement is a possible molecular synapomorphy for this suborder. The phylogenetic signal in mtgenomes is rigorously examined under the analytical regimens of parsimony, maximum likelihood and Bayesian inference, along with how gene inclusion/exclusion, data recoding, gap coding, and different partitioning schemes influence the phylogenetic reconstruction. When all available data are analyzed simultaneously, the monophyly of Orthoptera and its two suborders, Caelifera and Ensifera, are consistently recovered in the context of our taxon sampling, regardless of the optimality criteria. When protein-coding genes are analyzed as a single partition, nearly identical topology to the combined analyses is recovered, suggesting that much of the signals of the mtgenome come from the protein-coding genes. Transfer and ribosomal RNAs perform poorly when analyzed individually, but contribute signal when analyzed in combination with the protein-coding genes. Inclusion of third codon position of the protein-coding genes does not negatively affect the phylogenetic reconstruction when all genes are analyzed together, whereas recoding of the protein-coding genes into amino acid sequences introduces artificial resolution. Over-partitioning in a Bayesian framework appears to have a negative effect in achieving convergence. Our findings suggest that the best phylogenetic inferences are made when all available nucleotide data from the mtgenome are analyzed simultaneously, and that the mtgenome data can resolve over a wide time scale from the Permian (approximately 260 MYA) to the Tertiary (approximately 50 MYA).
C. H. F. Rowell - One of the best experts on this subject based on the ideXlab platform.
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Inferences about orthopteroid phylogeny and molecular evolution from small subunit nuclear ribosomal DNA sequences
Insect molecular biology, 1998Co-Authors: P. K. Flook, C. H. F. RowellAbstract:We determined DNA sequences of SSU rRNA genes in twenty-nine polyneopteran insect species and aligned these with homologues from eight other insects. In a phylogenetic analysis we recovered the classic divisions of Palaeoptera and Neoptera, with the latter divided into monophyletic Paraneoptera and Polyneoptera. The polyneopterans divided into three lineages: one includes the Grylloblattodea, Dermaptera and Plecoptera, the second contains the Blattodea, and the third (Orthopteroidea sensu Hennig) contains the Embiidina, Phasmida, and Orthoptera, in that order. The monophyly of the Orthoptera is supported by the analyses, as is the separation between taxa from its suborders Caelifera and Ensifera. The Caelifera are not always supported as a monophyletic group; the basal Tridactyloidea are separated from the rest of the Caelifera in some analyses. Inside of Tridactyloidea, the Acridoidea, Pamphagoidea, Pneumoroidea and Trigonopterygoidea are always recovered as a monophyletic group. We also examined the basal orthopteran relationships, with the specific aim of assessing the antiquity of the Ensifera. Character state reconstructions indicated that the ancestral ensiferan sequence is very similar to the ancestral orthopteran sequence. However, likelihood ratio tests rejected the null hypothesis of a molecular clock and we conclude that a change in substitution rate has occurred within the Orthoptera and several of the other polyneopteran orders. Similar observations have been made in holometabolous insects, suggesting that variation in substitution rate is a general feature of insect nuclear rRNA evolution.
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Phylogeny of the Caelifera and the Orthoptera as Derived from Ribosomal Gene Sequences
Journal of Orthoptera Research, 1998Co-Authors: C. H. F. Rowell, P. K. FlookAbstract:We used phylogenetic analysis of three different genomic regions (parts of the 18S nRNA gene and of the 12S and 16S mtRNA genes), singly and in combination, to position the Orthoptera within the Polyneoptera and to examine the higher systematics of the Caelifera. Analysis of the Ensifera was hindered by the fact that all the grylloid sequences are highly divergent and do not align readily with those of other orthopterans. Within the Polyneoptera the Orthoptera form a clade together with the Phasmida and Embiidina, which are their closest relatives. Both the Ensifera and the Caelifera are monophyletic groups. We propose the following division of the Caelifera into superfamilies, corresponding to the major branches of their phylogenetic tree: Tridactyloidea, Tetrigoidea, Eumastacoidea, Trigonopterygoidea s. nov. (including the Xyronotidae), Tanaoceroidea, Pyrgomorphoidea, Pneumoroidea, and Acridoidea s. nov. (including the Pamphagidae). The question as to whether the Proscopiidae are a component of the Eumastacoidea or a separate superfamily is not resolved. The classical families within the Tridactyloidea, Tetrigoidea, and Eumastacoidea are supported as unitary clades, as are some but not all of the traditional subfamilies of the Acrididae and Romaleidae. The oldest clades within the Acridoidea appear to be some lentulids, the Oedipodinae, and the Abracrini of the Ommatolampinae. Most of the acridoid clades, however, appear to have arisen more or less simultaneously at a slightly later date, and their branching order is not resolved in our analysis. We find little phylogenetic support for dividing the Acridoidea into more than one family.
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The phylogeny of the Caelifera (Insecta, Orthoptera) as deduced from mtrRNA gene sequences.
Molecular phylogenetics and evolution, 1997Co-Authors: P. K. Flook, C. H. F. RowellAbstract:Fragments of both mitochondrial ribosomal RNA genes of 32 Caeliferan taxa (representing six of the seven superfamilies) and six outgroup Orthopteroids were sequenced. The combined alignment length was 630 bp after removal of all ambiguously aligned positions. Separation for the basal taxa was problematic and analysis using the LogDet transformation indicated that shared base composition biases were a confounding factor. The suborder Caelifera and all traditional Caeliferan superfamilies except the Pamphagoidea are retrieved as monophyletic groups, though the Eumastacoidea lack significant bootstrap support. Of the traditional pamphagoid taxa, the Pamphagidae is embedded between classically acridid subfamilies, whereas Pyrgomorphidae is placed close to the Pneumoroidea. The morphological similarities of the Pyrgomorphidae and Pamphagidae may thus be homoplasic. A consensus tree based on five different methods of analysis indicated the following order: (Tridactyloidea, Tetrigoidea (Eumastacidae, Proscopiidae (Pneumoridae, Pyrgomorphidae (Acrididae + Pamphagidae)))).
Kurt K. Günther - One of the best experts on this subject based on the ideXlab platform.
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Die Tridactyloidea-Fauna Kolumbiens (Orthoptera, Caelifera) ‘The Tridactyloidea of Colombia (Orthoptera, Caelifera)’†
Deutsche Entomologische Zeitschrift, 2008Co-Authors: Kurt K. GüntherAbstract:The Tridactyloidea of Colombia are revised. Diagnoses and illustrations of all taxa are given. Keys for determination are included. All reliable records of distribution are mentioned. Important news to biology and ecology are inclosed. Mirhipipteryx schuchmanni sp. n., Mirhipipteryx lineata anchicayensis ssp. n. and Ellipes peruvianus macarenensis ssp. n. are described new to science. Neotridactylus australis (Bruner), N. occultus Gunther and Ripipteryx nodicornis Hebard are recorded for the first time from Colombia.
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Die Tridactyloidea des südlichen Afrika (Orthoptera, Caelifera)†
Deutsche Entomologische Zeitschrift, 2008Co-Authors: Kurt K. GüntherAbstract:The Tridactyloidea of Southern Africa (Orthoptera, Caelifera The African Tridactyloidea, especially from the southern parts of this continent (Madagascar included), are studied and revised with taxonomical and faunistical point of view. 41 species are found out. They belong to 6 genera: Tridactylus (3), Asiotridactylusgen. n. (2), Afrotridactylus (7), Xya (23), Paratridactylus (1) and Bruntridactylus (5). The genus Asiotridactylusgen. n., 11 species (Tridactylus angustussp. n., Asiotridactylus aethiopicussp. n., Bruntridactylus katangensissp. n., Xya albiantennatasp. n., albigenatasp. n., X. atrasp. n., X. aurantipessp. n., X. pronotovirgatasp. n., X. elytromaculatasp. n., X. tumbaensissp. n., X. uamensissp. n., X. univenatasp. n.) and a subspecies (Xya capensis albilobatassp. n.) are described new to science. Diagnoses with illustrations and keys for the determination of all african species are included. Supplementary redescriptions are added to several species hitherto known incompletely. Southern to the 15th degree of latitude S are recorded 4 genera and 16 species only: Tridactylus (2), Afrotridactylus (4), Xya (9) and Bruntridactylus (1). Many contributions to the distribution of the species are given.
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die tridactyloidea des sudlichen afrika orthoptera Caelifera
Deutsche Entomologische Zeitschrift, 1995Co-Authors: Kurt K. GüntherAbstract:The Tridactyloidea of Southern Africa (Orthoptera, Caelifera The African Tridactyloidea, especially from the southern parts of this continent (Madagascar included), are studied and revised with taxonomical and faunistical point of view. 41 species are found out. They belong to 6 genera: Tridactylus (3), Asiotridactylusgen. n. (2), Afrotridactylus (7), Xya (23), Paratridactylus (1) and Bruntridactylus (5). The genus Asiotridactylusgen. n., 11 species (Tridactylus angustussp. n., Asiotridactylus aethiopicussp. n., Bruntridactylus katangensissp. n., Xya albiantennatasp. n., albigenatasp. n., X. atrasp. n., X. aurantipessp. n., X. pronotovirgatasp. n., X. elytromaculatasp. n., X. tumbaensissp. n., X. uamensissp. n., X. univenatasp. n.) and a subspecies (Xya capensis albilobatassp. n.) are described new to science. Diagnoses with illustrations and keys for the determination of all african species are included. Supplementary redescriptions are added to several species hitherto known incompletely. Southern to the 15th degree of latitude S are recorded 4 genera and 16 species only: Tridactylus (2), Afrotridactylus (4), Xya (9) and Bruntridactylus (1). Many contributions to the distribution of the species are given.
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die tridactyloidea fauna kolumbiens orthoptera Caelifera the tridactyloidea of colombia orthoptera Caelifera
Deutsche Entomologische Zeitschrift, 1994Co-Authors: Kurt K. GüntherAbstract:The Tridactyloidea of Colombia are revised. Diagnoses and illustrations of all taxa are given. Keys for determination are included. All reliable records of distribution are mentioned. Important news to biology and ecology are inclosed. Mirhipipteryx schuchmanni sp. n., Mirhipipteryx lineata anchicayensis ssp. n. and Ellipes peruvianus macarenensis ssp. n. are described new to science. Neotridactylus australis (Bruner), N. occultus Gunther and Ripipteryx nodicornis Hebard are recorded for the first time from Colombia.
