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1.
Mol Ecol ; 32(23): 6161-6176, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36156326

RESUMO

Current understanding of ecological and evolutionary processes underlying island biodiversity is heavily shaped by empirical data from plants and birds, although arthropods comprise the overwhelming majority of known animal species, and as such can provide key insights into processes governing biodiversity. Novel high throughput sequencing (HTS) approaches are now emerging as powerful tools to overcome limitations in the availability of arthropod biodiversity data, and hence provide insights into these processes. Here, we explored how these tools might be most effectively exploited for comprehensive and comparable inventory and monitoring of insular arthropod biodiversity. We first reviewed the strengths, limitations and potential synergies among existing approaches of high throughput barcode sequencing. We considered how this could be complemented with deep learning approaches applied to image analysis to study arthropod biodiversity. We then explored how these approaches could be implemented within the framework of an island Genomic Observatories Network (iGON) for the advancement of fundamental and applied understanding of island biodiversity. To this end, we identified seven island biology themes at the interface of ecology, evolution and conservation biology, within which collective and harmonized efforts in HTS arthropod inventory could yield significant advances in island biodiversity research.


Assuntos
Artrópodes , Animais , Artrópodes/genética , Biodiversidade , Genômica , Plantas/genética , Código de Barras de DNA Taxonômico/métodos , Ilhas
2.
Mol Ecol ; 30(5): 1120-1135, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33432777

RESUMO

High-throughput sequencing (HTS) is increasingly being used for the characterization and monitoring of biodiversity. If applied in a structured way, across broad geographical scales, it offers the potential for a much deeper understanding of global biodiversity through the integration of massive quantities of molecular inventory data generated independently at local, regional and global scales. The universality, reliability and efficiency of HTS data can potentially facilitate the seamless linking of data among species assemblages from different sites, at different hierarchical levels of diversity, for any taxonomic group and regardless of prior taxonomic knowledge. However, collective international efforts are required to optimally exploit the potential of site-based HTS data for global integration and synthesis, efforts that at present are limited to the microbial domain. To contribute to the development of an analogous strategy for the nonmicrobial terrestrial domain, an international symposium entitled "Next Generation Biodiversity Monitoring" was held in November 2019 in Nicosia (Cyprus). The symposium brought together evolutionary geneticists, ecologists and biodiversity scientists involved in diverse regional and global initiatives using HTS as a core tool for biodiversity assessment. In this review, we summarize the consensus that emerged from the 3-day symposium. We converged on the opinion that an effective terrestrial Genomic Observatories network for global biodiversity integration and synthesis should be spatially led and strategically united under the umbrella of the metabarcoding approach. Subsequently, we outline an HTS-based strategy to collectively build an integrative framework for site-based biodiversity data generation.


Assuntos
Biodiversidade , Código de Barras de DNA Taxonômico , Chipre , Genômica , Reprodutibilidade dos Testes
3.
Genome ; 63(9): 407-436, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32579871

RESUMO

We report one year (2013-2014) of biomonitoring an insect community in a tropical old-growth rain forest, during construction of an industrial-level geothermal electricity project. This is the first-year reaction by the species-rich insect biodiversity; six subsequent years are being analyzed now. The site is on the margin of a UNESCO Natural World Heritage Site, Área de Conservación Guanacaste (ACG), in northwestern Costa Rica. This biomonitoring is part of Costa Rica's ongoing efforts to sustainably retain its wild biodiversity through biodevelopmental integration with its societies. Essential tools are geothermal engineering needs, entomological knowledge, insect species-rich forest, government-NGO integration, common sense, DNA barcoding for species-level identification, and Malaise traps. This research is tailored for integration with its society at the product level. We combine an academic view with on-site engineering decisions. This biomonitoring requires alpha-level DNA barcoding combined with centuries of morphology-based entomological taxonomy and ecology. Not all desired insect community analyses are performed; they are for data from subsequent years combined with this year. We provide enough analysis to be used by both guilds now. This biomonitoring has shown, for the first year, that the geothermal project impacts only the biodiversity within a zone less than 50 m from the project margin.


Assuntos
Biodiversidade , Código de Barras de DNA Taxonômico , Energia Geotérmica , Insetos/genética , Floresta Úmida , Animais , Costa Rica , DNA , Ecologia , Entomologia , Mariposas/genética , Especificidade da Espécie
4.
Mol Ecol ; 28(24): 5347-5359, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31674085

RESUMO

Mites (Arachnida: Acariformes, Parasitiformes) are the most abundant and species-rich group of arthropods in soil, but are also diverse in freshwater habitats, on plants, and as symbionts of larger animals. However, assessment of their diversity has been impeded by their small size and often cryptic morphology. As a consequence, published estimates of their species richness span more than two orders of magnitude (0.4-114 million). In this study we employ DNA barcoding and the Barcode Index Number (BIN) system to investigate mite diversity at over 1,800 sites across Canada, primarily from soil and litter habitats with smaller contributions from freshwater, plants, and animal hosts. Barcodes from 73,394 specimens revealed 7,077 BINs with representatives from all four orders (Ixodida, Mesostigmata, Sarcoptiformes, Trombidiformes) and 60% (186) of the known families. The BIN total is 2.4 times the number of species previously recorded from Canada (2,999), reflecting the unexpectedly high richness of several families. Richness projections suggest that more than 28,000 BINs occur at the sampled locations, indicating that the Canadian mite fauna almost certainly includes more than 30,000 species-a total similar to that for the most diverse insect order in Canada, Diptera. This unexpected diversity was partitioned into highly dissimilar, spatially-structured assemblages that likely reflect dispersal limitation and environmental heterogeneity. Further sampling of a greater diversity of habitats will refine understanding of mite diversity in Canada, but similar analyses in other geographic regions will be essential to ascertain their diversity at a global scale.


Assuntos
Código de Barras de DNA Taxonômico , Variação Genética/genética , Ácaros/genética , Animais , Aracnídeos/classificação , Aracnídeos/genética , Canadá , DNA/genética , Ecossistema , Ácaros/classificação
5.
Genome ; 62(3): 108-121, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30184444

RESUMO

Madagascar is a prime evolutionary hotspot globally, but its unique biodiversity is under threat, essentially from anthropogenic disturbance. There is a race against time to describe and protect the Madagascan endangered biota. Here we present a first molecular characterization of the micromoth fauna of Madagascar. We collected 1572 micromoths mainly using light traps in both natural and anthropogenically disturbed habitats in 24 localities across eastern and northwest Madagascar. We also collected 1384 specimens using a Malaise trap in a primary rain forest at Andasibe, eastern Madagascar. In total, we DNA barcoded 2956 specimens belonging to 1537 Barcode Index Numbers (BINs), 88.4% of which are new to BOLD. Only 1.7% of new BINs were assigned to species. Of 47 different families found, Dryadaulidae, Bucculatricidae, Bedelliidae, Batrachedridae, and Blastobasidae are newly reported for Madagascar and the recently recognized Tonzidae is confirmed. For test faunas of Canada and Australia, 98.9%-99.4% of Macroheterocera BINs exhibited the molecular synapomorphy of a phenylalanine in the 177th complete DNA barcode codon. Non-macroheteroceran BINs could thus be sifted out efficiently in the Malaise sample. The Madagascar micromoth fauna shows highest affinity with the Afrotropics (146 BINs also occur in the African continent). We found 22 recognised pests or invasive species, mostly occurring in disturbed habitats. Malaise trap samples show high temporal turnover and alpha diversity with as many as 507 BINs collected; of these, astonishingly, 499 (98.4%) were novel to BOLD and 292 (57.6%) were singletons. Our results provide a baseline for future surveys across the island.


Assuntos
Biodiversidade , Código de Barras de DNA Taxonômico/métodos , DNA/genética , Ecossistema , Espécies Introduzidas/estatística & dados numéricos , Mariposas/classificação , Mariposas/genética , Animais , DNA/análise , Madagáscar
6.
Genome ; 62(3): 96-107, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30278147

RESUMO

Biodiversity research in tropical ecosystems-popularized as the most biodiverse habitats on Earth-often neglects invertebrates, yet invertebrates represent the bulk of local species richness. Insect communities in particular remain strongly impeded by both Linnaean and Wallacean shortfalls, and identifying species often remains a formidable challenge inhibiting the use of these organisms as indicators for ecological and conservation studies. Here we use DNA barcoding as an alternative to the traditional taxonomic approach for characterizing and comparing the diversity of moth communities in two different ecosystems in Gabon. Though sampling remains very incomplete, as evidenced by the high proportion (59%) of species represented by singletons, our results reveal an outstanding diversity. With about 3500 specimens sequenced and representing 1385 BINs (Barcode Index Numbers, used as a proxy to species) in 23 families, the diversity of moths in the two sites sampled is higher than the current number of species listed for the entire country, highlighting the huge gap in biodiversity knowledge for this country. Both seasonal and spatial turnovers are strikingly high (18.3% of BINs shared between seasons, and 13.3% between sites) and draw attention to the need to account for these when running regional surveys. Our results also highlight the richness and singularity of savannah environments and emphasize the status of Central African ecosystems as hotspots of biodiversity.


Assuntos
Biodiversidade , Código de Barras de DNA Taxonômico/métodos , DNA/genética , Mariposas/classificação , Mariposas/genética , Clima Tropical , Animais , DNA/análise , Ecossistema , Gabão
7.
Genome ; 62(3): 85-95, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30257096

RESUMO

Monitoring changes in terrestrial arthropod communities over space and time requires a dramatic increase in the speed and accuracy of processing samples that cannot be achieved with morphological approaches. The combination of DNA barcoding and Malaise traps allows expedited, comprehensive inventories of species abundance whose cost will rapidly decline as high-throughput sequencing technologies advance. Aside from detailing protocols from specimen sorting to data release, this paper describes their use in a survey of arthropod diversity in a national park that examined 21 194 specimens representing 2255 species. These protocols can support arthropod monitoring programs at regional, national, and continental scales.


Assuntos
Artrópodes/classificação , Artrópodes/genética , Biodiversidade , Código de Barras de DNA Taxonômico/métodos , DNA/genética , Entomologia/instrumentação , Animais , DNA/análise , Filogenia , Especificidade da Espécie
8.
BMC Genomics ; 19(1): 219, 2018 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-29580219

RESUMO

BACKGROUND: Although high-throughput sequencers (HTS) have largely displaced their Sanger counterparts, the short read lengths and high error rates of most platforms constrain their utility for amplicon sequencing. The present study tests the capacity of single molecule, real-time (SMRT) sequencing implemented on the SEQUEL platform to overcome these limitations, employing 658 bp amplicons of the mitochondrial cytochrome c oxidase I gene as a model system. RESULTS: By examining templates from more than 5000 species and 20,000 specimens, the performance of SMRT sequencing was tested with amplicons showing wide variation in GC composition and varied sequence attributes. SMRT and Sanger sequences were very similar, but SMRT sequencing provided more complete coverage, especially for amplicons with homopolymer tracts. Because it can characterize amplicon pools from 10,000 DNA extracts in a single run, the SEQUEL can reduce greatly reduce sequencing costs in comparison to first (Sanger) and second generation platforms (Illumina, Ion). CONCLUSIONS: SMRT analysis generates high-fidelity sequences from amplicons with varying GC content and is resilient to homopolymer tracts. Analytical costs are low, substantially less than those for first or second generation sequencers. When implemented on the SEQUEL platform, SMRT analysis enables massive amplicon characterization because each instrument can recover sequences from more than 5 million DNA extracts a year.


Assuntos
Artrópodes/genética , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Reação em Cadeia da Polimerase/métodos , Análise de Sequência de DNA/métodos , Animais , Artrópodes/classificação , Variação Genética
9.
Genome ; 59(9): 671-84, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27549513

RESUMO

It is essential that any DNA barcode reference library be based upon correctly identified specimens. The Barcode of Life Data Systems (BOLD) requires information such as images, geo-referencing, and details on the museum holding the voucher specimen for each barcode record to aid recognition of potential misidentifications. Nevertheless, there are misidentifications and incomplete identifications (e.g., to a genus or family) on BOLD, mainly for species from tropical regions. Unfortunately, experts are often unavailable to correct taxonomic assignments due to time constraints and the lack of specialists for many groups and regions. However, considerable progress could be made if barcode records were available for all type specimens. As a result of recent improvements in analytical protocols, it is now possible to recover barcode sequences from museum specimens that date to the start of taxonomic work in the 18th century. The present study discusses success in the recovery of DNA barcode sequences from 2805 type specimens of geometrid moths which represent 1965 species, corresponding to about 9% of the 23 000 described species in this family worldwide and including 1875 taxa represented by name-bearing types. Sequencing success was high (73% of specimens), even for specimens that were more than a century old. Several case studies are discussed to show the efficiency, reliability, and sustainability of this approach.


Assuntos
Biodiversidade , Código de Barras de DNA Taxonômico , Insetos/classificação , Insetos/genética , Animais , DNA , Lepidópteros , Técnicas de Amplificação de Ácido Nucleico , Filogenia , Análise de Sequência de DNA
10.
Commun Biol ; 7(1): 552, 2024 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-38720028

RESUMO

Global biodiversity gradients are generally expected to reflect greater species replacement closer to the equator. However, empirical validation of global biodiversity gradients largely relies on vertebrates, plants, and other less diverse taxa. Here we assess the temporal and spatial dynamics of global arthropod biodiversity dynamics using a beta-diversity framework. Sampling includes 129 sampling sites whereby malaise traps are deployed to monitor temporal changes in arthropod communities. Overall, we encountered more than 150,000 unique barcode index numbers (BINs) (i.e. species proxies). We assess between site differences in community diversity using beta-diversity and the partitioned components of species replacement and richness difference. Global total beta-diversity (dissimilarity) increases with decreasing latitude, greater spatial distance and greater temporal distance. Species replacement and richness difference patterns vary across biogeographic regions. Our findings support long-standing, general expectations of global biodiversity patterns. However, we also show that the underlying processes driving patterns may be regionally linked.


Assuntos
Artrópodes , Biodiversidade , Animais , Artrópodes/classificação , Artrópodes/fisiologia , Geografia , Análise Espaço-Temporal
11.
Zootaxa ; 3749: 1-93, 2013 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-25113597

RESUMO

This study reports 30 species of Lepidoptera previously known from either the Palearctic or the Nearctic that are newly recorded as Holarctic. For 28 of these species, their intercontinental distributions were initially detected through DNA barcode analysis and subsequently confirmed by morphological examination; two Palearctic species were first detected in North America through morphology and then barcoded. When possible, the origin and status of each species (introduced, overlooked Holarctic species, or unknowingly re-described) is discussed, and its morphology is diagnosed and illustrated. The species involved include Tineidae: Scardia amurensis Zagulajev, Triaxomera parasitella (Hübner), Nemapogon cloacella (Haworth), Elatobia montelliella (Schantz), Tinea svenssoni Opheim; Gracillariidae: Caloptilia suberinella (Tengström), Parornix betulae (Stainton); Phyllonorycter maestingella (Müller); Yponomeutidae: Paraswammerdamia albicapitella (Scharfenberg), P. conspersella (Tengström); Plutellidae: Plutella hyperboreella Strand; Lyonetiidae: Lyonetia pulverulentella Zeller; Autostichidae: Oegoconia deauratella (Herrich-Schäffer), O. novimundi (Busck); Blastobasidae: Blastobasis glandulella (Riley), B. maroccanella (Amsel), B. tarda Meyrick; Depressariidae: Agonopterix conterminella (Zeller), Depressaria depressana (F.); Coleophoridae: Coleophora atriplicis Meyrick, C. glitzella Hofmann, C. granulatella Zeller, C. texanella Chambers, C. vitisella Gregson; Scythrididae: Scythris sinensis (Felder & Rogenhofer); Gelechiidae: Altenia perspersella (Wocke), Gnorimoschema jalavai Povolný, Scrobipalpa acuminatella (Sircom), Sophronia gelidella Nordman; Choreutidae: Anthophila fabriciana (L.); and Tortricidae: Phiaris bipunctana (F.). These cases of previously unrecognized faunal overlap have led to their redescription in several instances. Five new synonyms are proposed: Blastobasis glandulella (Riley, 1871) = B. huemeri Sinev, 1993, syn. nov.; B. tarda Meyrick, 1902 = Neoblastobasis ligurica Nel & Varenne, 2004, syn. nov.; Coleophora atriplicis Meyrick, 1928 = C. cervinella McDunnough, 1946, syn. nov.; C. texanella Chambers, 1878 = C. coxi Baldizzone & van der Wolf, 2007, syn. nov., and = C. vagans Walsingham, 1907, syn. nov. Lectotypes are designated for Blastobasis tarda Meyrick and Coleophora texanella Chambers. Type specimens were examined where pertinent to establish new synonymies. We identify 12 previously overlooked cases of species introductions, highlighting the power of DNA barcoding as a tool for biosurveillance.


Assuntos
Código de Barras de DNA Taxonômico , Lepidópteros/classificação , Lepidópteros/genética , Animais , Feminino , Lepidópteros/anatomia & histologia , Masculino , Especificidade da Espécie
12.
Biodivers Data J ; 11: e100677, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38327333

RESUMO

Natural history collections are the physical repositories of our knowledge on species, the entities of biodiversity. Making this knowledge accessible to society - through, for example, digitisation or the construction of a validated, global DNA barcode library - is of crucial importance. To this end, we developed and streamlined a workflow for 'museum harvesting' of authoritatively identified Diptera specimens from the Smithsonian Institution's National Museum of Natural History. Our detailed workflow includes both on-site and off-site processing through specimen selection, labelling, imaging, tissue sampling, databasing and DNA barcoding. This approach was tested by harvesting and DNA barcoding 941 voucher specimens, representing 32 families, 819 genera and 695 identified species collected from 100 countries. We recovered 867 sequences (> 0 base pairs) with a sequencing success of 88.8% (727 of 819 sequenced genera gained a barcode > 300 base pairs). While Sanger-based methods were more effective for recently-collected specimens, the methods employing next-generation sequencing recovered barcodes for specimens over a century old. The utility of the newly-generated reference barcodes is demonstrated by the subsequent taxonomic assignment of nearly 5000 specimen records in the Barcode of Life Data Systems.

13.
Biodivers Data J ; 11: e100904, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38327288

RESUMO

The use of DNA barcoding has revolutionised biodiversity science, but its application depends on the existence of comprehensive and reliable reference libraries. For many poorly known taxa, such reference sequences are missing even at higher-level taxonomic scales. We harvested the collections of the Smithsonian's National Museum of Natural History (USNM) to generate DNA barcoding sequences for genera of terrestrial arthropods previously not recorded in one or more major public sequence databases. Our workflow used a mix of Sanger and Next-Generation Sequencing (NGS) approaches to maximise sequence recovery while ensuring affordable cost. In total, COI sequences were obtained for 5,686 specimens belonging to 3,737 determined species in 3,886 genera and 205 families distributed in 137 countries. Success rates varied widely according to collection data and focal taxon. NGS helped recover sequences of specimens that failed a previous run of Sanger sequencing. Success rates and the optimal balance between Sanger and NGS are the most important drivers to maximise output and minimise cost in future projects. The corresponding sequence and taxonomic data can be accessed through the Barcode of Life Data System, GenBank, the Global Biodiversity Information Facility, the Global Genome Biodiversity Network Data Portal and the NMNH data portal.

14.
Gigascience ; 112022 07 19.
Artigo em Inglês | MEDLINE | ID: mdl-35852418

RESUMO

Metazoan metabarcoding is emerging as an essential strategy for inventorying biodiversity, with diverse projects currently generating massive quantities of community-level data. The potential for integrating across such data sets offers new opportunities to better understand biodiversity and how it might respond to global change. However, large-scale syntheses may be compromised if metabarcoding workflows differ from each other. There are ongoing efforts to improve standardization for the reporting of inventory data. However, harmonization at the stage of generating metabarcode data has yet to be addressed. A modular framework for harmonized data generation offers a pathway to navigate the complex structure of terrestrial metazoan biodiversity. Here, through our collective expertise as practitioners, method developers, and researchers leading metabarcoding initiatives to inventory terrestrial biodiversity, we seek to initiate a harmonized framework for metabarcode data generation, with a terrestrial arthropod module. We develop an initial set of submodules covering the 5 main steps of metabarcode data generation: (i) sample acquisition; (ii) sample processing; (iii) DNA extraction; (iv) polymerase chain reaction amplification, library preparation, and sequencing; and (v) DNA sequence and metadata deposition, providing a backbone for a terrestrial arthropod module. To achieve this, we (i) identified key points for harmonization, (ii) reviewed the current state of the art, and (iii) distilled existing knowledge within submodules, thus promoting best practice by providing guidelines and recommendations to reduce the universe of methodological options. We advocate the adoption and further development of the terrestrial arthropod module. We further encourage the development of modules for other biodiversity fractions as an essential step toward large-scale biodiversity synthesis through harmonization.


Assuntos
Artrópodes , Animais , Artrópodes/genética , Biodiversidade , Código de Barras de DNA Taxonômico , Estudos Longitudinais
15.
Sci Rep ; 11(1): 15922, 2021 08 05.
Artigo em Inglês | MEDLINE | ID: mdl-34354125

RESUMO

Although mites (Acari) are abundant in many terrestrial and freshwater ecosystems, their diversity is poorly understood. Since most mite species can be distinguished by variation in the DNA barcode region of cytochrome c oxidase I, the Barcode Index Number (BIN) system provides a reliable species proxy that facilitates large-scale surveys. Such analysis reveals many new BINs that can only be identified as Acari until they are examined by a taxonomic specialist. This study demonstrates that the Barcode of Life Datasystem's identification engine (BOLD ID) generally delivers correct ordinal and family assignments from both full-length DNA barcodes and their truncated versions gathered in metabarcoding studies. This result was demonstrated by examining BOLD ID's capacity to assign 7021 mite BINs to their correct order (4) and family (189). Identification success improved with sequence length and taxon coverage but varied among orders indicating the need for lineage-specific thresholds. A strict sequence similarity threshold (86.6%) prevented all ordinal misassignments and allowed the identification of 78.6% of the 7021 BINs. However, higher thresholds were required to eliminate family misassignments for Sarcoptiformes (89.9%), and Trombidiformes (91.4%), consequently reducing the proportion of BINs identified to 68.6%. Lineages with low barcode coverage in the reference library should be prioritized for barcode library expansion to improve assignment success.


Assuntos
Ácaros e Carrapatos/genética , Código de Barras de DNA Taxonômico/métodos , Complexo IV da Cadeia de Transporte de Elétrons/genética , Animais , Biodiversidade , DNA/genética , Ecossistema , Biblioteca Gênica , Técnicas Genéticas , Ácaros/genética
16.
Gigascience ; 10(3)2021 03 25.
Artigo em Inglês | MEDLINE | ID: mdl-33764469

RESUMO

BACKGROUND: Rickettsia are intracellular bacteria best known as the causative agents of human and animal diseases. Although these medically important Rickettsia are often transmitted via haematophagous arthropods, other Rickettsia, such as those in the Torix group, appear to reside exclusively in invertebrates and protists with no secondary vertebrate host. Importantly, little is known about the diversity or host range of Torix group Rickettsia. RESULTS: This study describes the serendipitous discovery of Rickettsia amplicons in the Barcode of Life Data System (BOLD), a sequence database specifically designed for the curation of mitochondrial DNA barcodes. Of 184,585 barcode sequences analysed, Rickettsia is observed in ∼0.41% of barcode submissions and is more likely to be found than Wolbachia (0.17%). The Torix group of Rickettsia are shown to account for 95% of all unintended amplifications from the genus. A further targeted PCR screen of 1,612 individuals from 169 terrestrial and aquatic invertebrate species identified mostly Torix strains and supports the "aquatic hot spot" hypothesis for Torix infection. Furthermore, the analysis of 1,341 SRA deposits indicates that Torix infections represent a significant proportion of all Rickettsia symbioses found in arthropod genome projects. CONCLUSIONS: This study supports a previous hypothesis that suggests that Torix Rickettsia are overrepresented in aquatic insects. In addition, multiple methods reveal further putative hot spots of Torix Rickettsia infection, including in phloem-feeding bugs, parasitoid wasps, spiders, and vectors of disease. The unknown host effects and transmission strategies of these endosymbionts make these newly discovered associations important to inform future directions of investigation involving the understudied Torix Rickettsia.


Assuntos
Artrópodes , Rickettsia , Animais , Artrópodes/genética , Sequência de Bases , Humanos , Filogenia , Rickettsia/genética , Simbiose
17.
PeerJ ; 9: e11157, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33976967

RESUMO

Although the butterflies of North America have received considerable taxonomic attention, overlooked species and instances of hybridization continue to be revealed. The present study assembles a DNA barcode reference library for this fauna to identify groups whose patterns of sequence variation suggest the need for further taxonomic study. Based on 14,626 records from 814 species, DNA barcodes were obtained for 96% of the fauna. The maximum intraspecific distance averaged 1/4 the minimum distance to the nearest neighbor, producing a barcode gap in 76% of the species. Most species (80%) were monophyletic, the others were para- or polyphyletic. Although 15% of currently recognized species shared barcodes, the incidence of such taxa was far higher in regions exposed to Pleistocene glaciations than in those that were ice-free. Nearly 10% of species displayed high intraspecific variation (>2.5%), suggesting the need for further investigation to assess potential cryptic diversity. Aside from aiding the identification of all life stages of North American butterflies, the reference library has provided new perspectives on the incidence of both cryptic and potentially over-split species, setting the stage for future studies that can further explore the evolutionary dynamics of this group.

18.
Biol Lett ; 6(3): 359-62, 2010 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-20015856

RESUMO

This study reports DNA barcodes for more than 1300 Lepidoptera species from the eastern half of North America, establishing that 99.3 per cent of these species possess diagnostic barcode sequences. Intraspecific divergences averaged just 0.43 per cent among this assemblage, but most values were lower. The mean was elevated by deep barcode divergences (greater than 2%) in 5.1 per cent of the species, often involving the sympatric occurrence of two barcode clusters. A few of these cases have been analysed in detail, revealing species overlooked by the current taxonomic system. This study also provided a large-scale test of the extent of regional divergence in barcode sequences, indicating that geographical differentiation in the Lepidoptera of eastern North America is small, even when comparisons involve populations as much as 2800 km apart. The present results affirm that a highly effective system for the identification of Lepidoptera in this region can be built with few records per species because of the limited intra-specific variation. As most terrestrial and marine taxa are likely to possess a similar pattern of population structure, an effective DNA-based identification system can be developed with modest effort.


Assuntos
DNA/genética , Processamento Eletrônico de Dados , Animais , Classificação/métodos , Lepidópteros/classificação , Lepidópteros/genética , Filogenia
19.
Zookeys ; (819): 169-186, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30713437

RESUMO

The currently documented fauna of described species of myriapods in Canada includes 54 Chilopoda, 66 Diplopoda, 23 Pauropoda, and two Symphyla, representing increases of 24, 23, 23, and one species, respectively, since 1979. Of the 145 myriapod species currently documented, 40 species are not native to Canada. The myriapods have not been well documented with DNA barcodes and no barcodes are available for Pauropoda. It is conservatively estimated that at least 93 additional myriapods species will be discovered in Canada: Chilopoda (40), Diplopoda (29), Pauropoda (17), and Symphyla (seven). In general, there is a serious dearth of knowledge about myriapods in Canada, and systematics research and surveys continue to be needed to help document the diversity and distribution of these groups in the country.

20.
Zookeys ; (819): 311-360, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30713450

RESUMO

A summary of the numbers of species of the 83 families of Hymenoptera recorded in Canada is provided. In total, 8757 described species are recorded compared to approximately 6000 in 1979, which is a 46% increase. Of the families recognized in 1979, three have been newly recorded to Canada since the previous survey: Anaxyelidae (Anaxyleoidea), Liopteridae (Cynipoidea), and Mymarommatidae (Mymarommatoidea). More than 18,400 BINs of Canadian Hymenoptera are available in the Barcode of Life Data Systems (Ratnasingham and Hebert 2007) implying that nearly 9650 undescribed or unrecorded species of Hymenoptera may be present in Canada (and more than 10,300 when taking into account additional species that have not been DNA barcoded). The estimated number of unrecorded species is very similar to that of 1979 (10,637 species), but the percentage of the fauna described/recorded has increased from 36% in 1979 to approximately 45% in 2018. Summaries of the state of knowledge of the major groups of Hymenoptera are presented, including brief comments on numbers of species, biology, changes in classification since 1979, and relevant taxonomic references.

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