DNA barcoding gap: reliable species identification over morphological and geographical scales

@article{andek2015DNABG,
  title={DNA barcoding gap: reliable species identification over morphological and geographical scales},
  author={Klemen {\vC}andek and Matja{\vz} Kuntner},
  journal={Molecular Ecology Resources},
  year={2015},
  volume={15}
}
The philosophical basis and utility of DNA barcoding have been a subject of numerous debates. While most literature embraces it, some studies continue to question its use in dipterans, butterflies and marine gastropods. Here, we explore the utility of DNA barcoding in identifying spider species that vary in taxonomic affiliation, morphological diagnosibility and geographic distribution. Our first test searched for a ‘barcoding gap’ by comparing intra‐ and interspecific means, medians and… 
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References

SHOWING 1-10 OF 84 REFERENCES
DNA barcoding and taxonomy in Diptera: a tale of high intraspecific variability and low identification success.
TLDR
An outlook on the prospects of obtaining complete barcode databases and the future use of DNA sequences in a modern integrative taxonomy is concluded.
The Effect of Geographical Scale of Sampling on DNA Barcoding
TLDR
A CO1 data set of aquatic predaceous diving beetles of the tribe Agabini is presented and it is shown that even if samples are collected to maximize the geographical coverage, up to 70 individuals are required to sample 95% of intraspecific variation, showing that the geographical scale of sampling has a critical impact on the global application of DNA barcoding.
DNA barcodes distinguish species of tropical Lepidoptera.
TLDR
It is shown that cytochrome c oxidase I DNA barcodes effectively discriminate among species in three Lepidoptera families from Area de Conservación Guanacaste in northwestern Costa Rica, suggesting DNA barcoding will significantly aid species identification and discovery in tropical settings.
DNA Barcoding: Error Rates Based on Comprehensive Sampling
TLDR
This is the first examination of barcoding performance in a comprehensively sampled, diverse group (cypraeid marine gastropods, or cowries) and employs a novel phylogenetic approach to calculate intraspecific variation and interspecific divergence.
DNA barcodes for 1/1000 of the animal kingdom
TLDR
It is confirmed 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, and an effective DNA-based identification system can be developed with modest effort.
DNA Barcoding as a Tool for Elucidating Species Delineation in Wide-ranging Species as Illustrated by Owls (Tytonidae and Strigidae)
TLDR
Phylogenetic analysis of the T. alba samples gives very strong support for an Old World alba-clade (three subspecies) and a New World furcata-clades (four sub species) that are genetically equidistant, suggesting that barn owl of the Old World is indeed best considered a separate species different from that of the New World.
Molecular Identification of Birds: Performance of Distance-Based DNA Barcoding in Three Genes to Delimit Parapatric Species
TLDR
The results confirm the existence of a wide gap between intra- and interspecies divergences for both cox1 and cob, and indicate that distance-based DNA barcoding provides sufficient information to identify and delineate bird species in 98% of all possible pairwise comparisons.
Revisiting species delimitation within the genus Oxystele using DNA barcoding approach
TLDR
This analysis delimits five molecular operational taxonomic units (MOTUs), and distinguishes O. impervia from O. variegata, revealing important discrepancies between MOTUs and morphology-based species identification and discussing alternative hypotheses that can account for this.
Does the DNA barcoding gap exist? – a case study in blue butterflies (Lepidoptera: Lycaenidae)
TLDR
An analysis of intra- and interspecific variation in the butterfly family Lycaenidae which includes a well-sampled clade with a peculiar characteristic that facilitates the recognition of species as reproductively isolated units even in allopatric populations indicates that the "barcoding gap" is an artifact of insufficient sampling across taxa.
Identifying spiders through DNA barcodes
TLDR
This study demonstrates that sequence diversity in a standard segment of the mitochondrial gene coding for cytochrome c oxidase I (COI) is highly effective in discriminating spider species and establishes the potential of COI as a rapid and accurate identification tool for biodiversity surveys of spiders.
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