A new taxonomist-curated reference library of DNA barcodes for Neotropical electric fish (Teleostei: Gymnotiformes)

DNA barcoding is a useful tool for identifying species; however, successful barcode-based identification requires a reference library of barcode sequences from accurately identified specimens. Here we present a reference library of COI barcode sequences for the Neotropical electric knifefish, order Gymnotiformes (Teleostei: Ostariophysi), a model taxon for studies of tropical diversification and biogeography, genomics, behaviour and neurobiology. Our library contains barcodes for 167 of the c. 270 valid species of gymnotiforms derived from geo-referenced museum voucher specimens, and includes sequences from 26 type specimens and 21 specimens from type localities, most of which we collected. To assess the state of gymnotiform barcodes in two main public barcode repositories, GenBank and BOLD, we compared the barcodes in these databases to our reference library. Our analysis shows that a considerable proportion of gymnotiform barcodes in GenBank and BOLD are mis- or unidentified. We encourage taxonomists to develop and publish barcode reference libraries composed of carefully curated barcode sequences.