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We reviewed the availability of cytochrome c oxidase subunit I (COI) sequences for 2534 North American freshwater invertebrate genera in public databases (GenBank and Barcode of Life Data Systems) and assessed representation of genera commonly encountered in the Canadian Aquatic Biomonitoring Network (CABIN) database. COI sequence records were available for 61.2% of North American genera and 72.4% of Insecta genera in public databases. Mollusca (73.9%) and Nematoda (15.4%) were the best and worst represented groups, respectively. In CABIN, 85.4% of genera had COI sequence records, and 95.2% of genera occurring in >1% of samples were represented. Genera absent from CABIN tended to be uncommon or members of groups not routinely used for biomonitoring purposes. On average, 94.1% of genera in well-identified samples had associated sequence data. To leverage the full potential of genomics approaches, we must expand DNA-barcode reference libraries for poorly described components of freshwater food webs. Some genera appear to be well represented (e.g., Eukiefferiella), but deposited sequences represent few sampling localities or few species and lead to underestimation of sequence diversity at the genus level and reduced confidence in identifications. Public COI libraries are sufficiently populated to permit routine application of genomics tools in biomonitoring, and ongoing quality assurance/quality control should include re-evaluation as new COI reference sequences are added or taxonomic hierarchies change. Next, we must understand whether and how established biomonitoring approaches can capitalize on high-throughput sequencing tools. Biomonitoring approaches that use genomics data to facilitate structural and functional assessments are fertile ground for future investigation and will benefit from continued improvement of publicly available sequence libraries. [ABSTRACT FROM AUTHOR]

Biodiversity metrics are critical for assessment and monitoring of ecosystems threatened by anthropogenic stressors. Existing sorting and identification methods are too expensive and labour-intensive to be scaled up to meet management needs. Alternately, a high-throughput DNA sequencing approach could be used to determine biodiversity metrics from bulk environmental samples collected as part of a large-scale biomonitoring program. Here we show that both morphological and DNA sequence-based analyses are suitable for recovery of individual taxonomic richness, estimation of proportional abundance, and calculation of biodiversity metrics using a set of 24 benthic samples collected in the Peace-Athabasca Delta region of Canada. The high-throughput sequencing approach was able to recover all metrics with a higher degree of taxonomic resolution than morphological analysis. The reduced cost and increased capacity of DNA sequence-based approaches will finally allow environmental monitoring programs to operate at the geographical and temporal scale required by industrial and regulatory end-users. [ABSTRACT FROM AUTHOR]

Members of the family Conopidae (Diptera) have been the focus of little targeted phylogenetic research. The most comprehensive test of phylogenetic support for the present subfamily classification of Conopidae is presented here using 66 specimens, including 59 species of Conopidae and seven outgroup taxa. Relationships among subfamily clades are also explored. A total of 6824 bp of DNA sequence data from five gene regions (12S ribosomal DNA, cytochrome c oxidase subunit I, cytochrome b, 28S ribosomal DNA and alanyl-tRNA synthetase) are combined with 111 morphological characters in a combined analysis using both parsimony and Bayesian methods. Parsimony analysis recovers three shortest trees. Bayesian analysis recovers a nearly identical tree. Five monophyletic subfamilies of Conopidae are recovered. The rarely acknowledged Zodioninae is restored, including the genera Zodion and Parazodion. The genus Sicus is removed from Myopinae. Morphological synapomorphies are discussed for each subfamily and inter-subfamily clade, including a comprehensive review of the character interpretaions of previous authors. Included are detailed comparative illustrations of male and female genitalia of representatives of all five subfamilies with new morphological interpretation. [ABSTRACT FROM AUTHOR]

Since 2005, advances in next-generation sequencing technologies have revolutionized biological science. The analysis of environmental DNA through the use of specific gene markers such as species-specific DNA barcodes has been a key application of next-generation sequencing technologies in ecological and environmental research. Access to parallel, massive amounts of sequencing data, as well as subsequent improvements in read length and throughput of different sequencing platforms, is leading to a better representation of sample diversity at a reasonable cost. New technologies are being developed rapidly and have the potential to dramatically accelerate ecological and environmental research. The fast pace of development and improvements in next-generation sequencing technologies can reflect on broader and more robust applications in environmental DNA research. Here, we review the advantages and limitations of current next-generation sequencing technologies in regard to their application for environmental DNA analysis. [ABSTRACT FROM AUTHOR]

DNA sequence data from a variety of mitochondrial and nuclear gene regions are significant components of phylogenetic research in entomology. Polymerase chain reaction (PCR) amplification primers for many gene regions have been developed that are specific to a range of dipteran groups. Here, we review the existing Diptera-specific PCR amplification primers that have been published for 11 mitochondrial and nuclear gene regions: 12S small ribosomal subunit, cytochrome b, cytochrome oxidase c subunit I, 28S ribosomal RNA, alanyl-tRNA synthetase, the carbamoyl phosphate synthase region of CAD, elongation factor-1α, 6-phosphogluconate dehydrogenase, triose phosphate isomerase, white, and wingless. We also have designed in total 94 new PCR amplification primers for use in these same gene regions. Our new primers have been developed and tested using our DNA sequence database of >1,600 specimens representing 40 families of Diptera. All of the past and newly developed primer sequences are presented in tables, and their locations are shown on gene maps. This combined data will facilitate future molecular phylogenetic research within Diptera. [ABSTRACT FROM AUTHOR]

Abstract: The first attempt to phylogenetically place Conopidae using molecular characters, as well as the largest molecular analysis of relationships within Schizophora (Diptera) to date, is presented. Twenty-eight taxa from 11 acalyptrate families and seven acalyptrate superfamilies are represented. Nearly 12,800bp of sequence data from 10 genes representing both mitochondrial (cytochrome oxidase I (COI), cytochrome b (cytB), and 12S) and nuclear genes (28S, the carbamoyl phosphate synthetase region of CAD (CAD), elongation factor-1α (EF-1α), white, alanyl-tRNA synthetase (AATS), triose phosphate isomerase (TPI), and phosphogluconate dehydrogenase (PGD)) are analysed. Parsimony and Bayesian analyses strongly support the monophyly of both Conopidae and Schizophora. While in the parsimony analysis, Conopidae are placed as sister to the remaining Schizophora, the Bayesian analysis recovers a Conopidae+Lauxaniidae clade. The value of nuclear, mitochondrial, ribosomal, and protein-coding gene sequence data for answering phylogenetic questions at different levels of divergence is evaluated. [Copyright &y& Elsevier]

Abstract: A procedure for the isolation of target PCR bands from multiplex PCR products using the E-Gel® iBase Power System, an E-Gel® Safe Imager™ Real-Time Transilluminator, and E-Gel® CloneWell 0.8% SYBR Safe™ agarose cassettes is presented. The collected isolates are suitable for direct use in sequencing reactions without need of further purification. Reductions in time spent per sample and cost per sequence produced compared to traditional “band-cutting” methods are demonstrated. An added benefit is that the new procedure does not require exposure to ethidium bromide or ultraviolet radiation. [Copyright &y& Elsevier]