DNA barcode library for European gelechiidae (Lepidoptera) suggests greatly underestimated species diversity
Citation
Huemer, P., Karsholt, O., Aarvik, L., Berggren, K., Bidzilya, O., Junnilainen, J., Landry, J.F., Mutanen, M., Nupponen, K., Segerer, A., Šumpich, J., Wieser, C., Wiesmair, B., Hebert, P.D.N. (2020). DNA barcode library for European gelechiidae (Lepidoptera) suggests greatly underestimated species diversity. ZooKeys, [online] 2020(921), 141-157. http://dx.doi.org/10.3897/zookeys.921.49199
Plain language summary
This article, which results from extensive multinational collaboration, introduces a newly developed and comprehensive reference library (database) of DNA (genetic) barcodes for a family of moths. The library documents DNA for over 750 species and focuses primarily on Europe, and includes many species also present in Canada, either introduced as alien invasive species or native to the Canadian insect fauna. Gelechiidae moths are a family of very small moths that comprises several thousands of species worldwide, many of which are agricultural pests like the tomato pinworm, the pepper flower-bud moth, and the potato tuberworm. They are notoriously difficult to identify using only morphology (e.g. shape, size, color, etc.), such as distinguishing pest from non-pest species, or native vs alien. A DNA library such as this one forms the core of DNA-based identification tools. It also serves to reveal potentially cryptic species (undetected by morphology), to detect the presence of invasive alien species, and to target future taxonomic research.
Abstract
For the first time, a nearly complete barcode library for European Gelechiidae is provided. DNA barcode sequences (COI gene – cytochrome c oxidase 1) from 751 out of 865 nominal species, belonging to 105 genera, were successfully recovered. A total of 741 species represented by specimens with sequences ≥ 500bp and an additional ten species represented by specimens with shorter sequences were used to produce 53 NJ trees. Intraspecific barcode divergence averaged only 0.54% whereas distance to the Near-est-Neighbour species averaged 5.58%. Of these, 710 species possessed unique DNA barcodes, but 31 species could not be reliably discriminated because of barcode sharing or partial barcode overlap. Species discrimination based on the Barcode Index System (BIN) was successful for 668 out of 723 species which clustered from minimum one to maximum 22 unique BINs. Fifty-five species shared a BIN with up to four species and identification from DNA barcode data is uncertain. Finally, 65 clusters with a unique BIN remained unidentified to species level. These putative taxa, as well as 114 nominal species with more than one BIN, suggest the presence of considerable cryptic diversity, cases which should be examined in future revisionary studies.