High resolution DNA barcode library for European butterflies reveals continental patterns of mitochondrial genetic diversity

Vlad Dincă,Paul D N Hebert,Peter Huemer,Raluca Vodă,Roger Vila,Panu Somervuo,Martin Gascoigne-Pees,Leonardo Dapporto,Sylvain Cuvelier,Marko Mutanen

doi:10.1038/s42003-021-01834-7

Abstract

The study of global biodiversity will greatly benefit from access to comprehensive DNA barcode libraries at continental scale, but such datasets are still very rare. Here, we assemble the first high-resolution reference library for European butterflies that provides 97% taxon coverage (459 species) and 22,306 COI sequences. We estimate that we captured 62% of the total haplotype diversity and show that most species possess a few very common haplotypes and many rare ones. Specimens in the dataset have an average 95.3% probability of being correctly identified. Mitochondrial diversity displayed elevated haplotype richness in southern European refugia, establishing the generality of this key biogeographic pattern for an entire taxonomic group. Fifteen percent of the species are involved in barcode sharing, but two thirds of these cases may reflect the need for further taxonomic research. This dataset provides a unique resource for conservation and for studying evolutionary processes, cryptic species, phylogeography, and ecology.

Highlights

The study of global biodiversity will greatly benefit from access to comprehensive DNA barcode libraries at continental scale, but such datasets are still very rare
The assessment of dataset completeness in terms of mitochondrial genetic diversity was based on 404 species for which at least six c oxidase subunit 1 (COI) sequences/species were available
Recovery values ranged from a low of about 20% of haplotype diversity in 15 species (Hyponephele lupina was lowest at 9.5%), while recovery exceeded 80% for 124 species (30.7%) (Fig. 2a, Supplementary Data 3)

Summary

Introduction

The study of global biodiversity will greatly benefit from access to comprehensive DNA barcode libraries at continental scale, but such datasets are still very rare. DNA barcoding, the use of short, standardised genomic regions to facilitate species identification and discovery[1], has revolutionised the study of biodiversity This approach is effective for animals, where the 5’ region of mitochondrial cytochrome c oxidase subunit 1 (COI) aids both specimen identification and species discovery, while revealing phylogeographic and other eco-evolutionary processes (e.g.2–6). A key step towards the ultimate goal of revealing global biodiversity involves the development of taxonomically curated sequence libraries for major taxonomic assemblages on a continental or global scale In this context, Lepidoptera, one of the most diverse insect orders, is the taxonomic group which has gained the most intensive analysis with over 1.4 million DNA barcodes This is the case for European butterflies as knowledge of their distributions, ecology, and conservation status is arguably unequalled among invertebrates (e.g.14–16)

Methods

Results

Conclusion