An Incomplete European Barcode Library Has a Strong Impact on the Identification Success of Lepidoptera from Greece

Species identification by means of DNA barcodes depends essentially on the scope and quality of a relevant reference library. The first analysis of a large number (about 600 morphospecies) of southern European Lepidoptera (Greece: Peloponnese) shows both the advantages and disadvantages with regard to a reliable identification of Mediterranean species. We determined 946 DNA barcode sequences from 47 families, of which 929 sequences from 46 families were successfully assigned to a Barcode Index Number (BIN) in the global Barcode of Life Data Systems (BOLD) database. A species level identification for 485 BINs representing 477 Linnaean names was successful. These taxa include 34 new records for Greece. However, 128 BINs (c. 20% of the inventory) could not be attached to a Linnaean name from referenced sequences available in BOLD. Of these BINs, 99 are new and hence represent unique records for BOLD. Intra- and inter-BIN divergences are presented and discussed. An initial and preliminary in-depth analysis of randomly selected species indicates an incomplete DNA barcode library in terms of Linnean taxa, in addition to a considerable number of probably undescribed species. It is therefore strongly recommended that the already advanced European barcode library of Lepidoptera should be supplemented with not-yet-sequenced taxa from the Mediterranean.

Automated summary

Species identification using DNA barcodes relies on the quality and scope of a reference library. The analysis of southern European Lepidoptera species showed both advantages and disadvantages in identifying Mediterranean species reliably. It is recommended to supplement the European Lepidoptera barcode library with unsequenced taxa from the Mediterranean.