The Hemiptera (Insecta) of Canada: Constructing a Reference Library of DNA Barcodes

Abstract

DNA barcode reference libraries linked to voucher specimens create new opportunities for high-throughput identification and taxonomic re-evaluations. This study provides a DNA barcode library for about 45% of the recognized species of Canadian Hemiptera, and the publically available R workflow used for its generation. The current library is based on the analysis of 20,851 specimens including 1849 species belonging to 628 genera and 64 families. These individuals were assigned to 1867 Barcode Index Numbers (BINs), sequence clusters that often coincide with species recognized through prior taxonomy. Museum collections were a key source for identified specimens, but we also employed high-throughput collection methods that generated large numbers of unidentified specimens. Many of these specimens represented novel BINs that were subsequently identified by taxonomists, adding barcode coverage for additional species. Our analyses based on both approaches includes 94 species not listed in the most recent Canadian checklist, representing a potential 3% increase in the fauna. We discuss the development of our workflow in the context of prior DNA barcode library construction projects, emphasizing the importance of delineating a set of reference specimens to aid investigations in cases of nomenclatural and DNA barcode discordance. The identification for each specimen in the reference set can be annotated on the Barcode of Life Data System (BOLD), allowing experts to highlight questionable identifications; annotations can be added by any registered user of BOLD, and instructions for this are provided.

Species diversity can be overestimated by a fixed empirical threshold: insights from DNA barcoding of the genus Cletus (Hemiptera: Coreidae) and the meta‐analysis of COI data from previous phylogeographical studies

“…; Gwiazdowski et al . ). With regard to the COI data downloaded from GenBank, the maximum intraspecific genetic distances of 186 species (48.44%) exceed 3%, which indicates high intraspecific genetic divergences are common given comprehensive sampling.…”

DNA barcodes for bio-surveillance: regulated and economically important arthropod plant pests

“…Work on Diptera has similarly validated the effectiveness of DNA barcoding for the identification of species in this order, including some of the most important agricultural pests, such as fruit flies (Virgilio et al 2012) and leafminers (Amin et al 2014). Another study that examined 1849 species of Canadian Hemiptera assigned these species to 1867 BINs with high correspondence between species and BINs, but also revealed 27 species with high divergences suggestive of cryptic species complexes (Gwiazdowski et al 2015). Lepidoptera, the most intensively studied order, is represented by more than 100 000 BINs on BOLD.…”

A DNA barcode library for 5,200 German flies and midges (Insecta: Diptera) and its implications for metabarcoding‐based biomonitoring

“…Both the speed and costs associated with sequence characterization of a standardized DNA fragment can be improved using DNA barcoding. Usually DNA barcoding studies provide a basis for establishing the reference sequence libraries required to identify specimens of known species (Gwiazdowski, Foottit, Maw, & Hebert, ; Hebert, Cywinska, Ball, & Dewaard, ). Herein we additionally show that it is also an efficient method for registering unknown and taxonomically challenging species—so called “dark taxa” (Page, ).…”