Data from: A reliable DNA barcode reference library for the identification of the European shelf fish fauna

Valid fish species identification is an essential step both for scientific purpose and fisheries management. The traditional identification is mainly based on external morphological diagnostic characters, leading to inconsistent results in many cases. Here we provide a sequence reference library based on mitochondrial cytochrome c oxidase subunit I (COI) for a valid identification of 93 North Atlantic fish species originating from the North Sea and adjacent waters, including many commercially exploited species. Neighbour joining analysis based on K2P genetic distances formed monophyletic, non-overlapping clusters for all species with at ≥99% bootstrap support each. The minimum genetic distance to the nearest neighbor always exceeded the maximum intraspecific distance. A barcoding gap was displayed for the whole dataset as within species distances ranged from 0-2.35%, while interspecific distances varied between 3.15 and 28.09%. Distances between congeners were on average 51-fold higher than those within species. The validation of the sequence library by applying an arbitrary grading system demonstrated high taxonomic reliability of the DNA barcodes for 85% of the investigated fish species. Thus, the sequence library presented here can be confidently used as a benchmark for identification of at least two thirds of the typical fish species recorded for the North Sea.