A DNA barcode reference library for Swiss butterflies and forester moths as a tool for species identification, systematics and conservation

Abstract

Butterfly monitoring and Red List programs in Switzerland rely on a combination of observations and collection records to document changes in species distributions through time. While most butterflies can be identified using morphology, some taxa remain challenging, making it difficult to accurately map their distributions and develop appropriate conservation measures. In this paper, we explore the use of the DNA barcode (a fragment of the mitochondrial gene COI) as a tool for the identification of Swiss butterflies and forester moths (Rhopalocera and Zygaenidae). We present a national DNA barcode reference library including 868 sequences representing 217 out of 224 resident species, or 96.9% of Swiss fauna. DNA barcodes were diagnostic for nearly 90% of Swiss species. The remaining 10% represent cases of para- and polyphyly likely involving introgression or incomplete lineage sorting among closely related taxa. We demonstrate that integrative taxonomic methods incorporating a combination of morphological and genetic techniques result in a rate of species identification of over 96% in females and over 98% in males, higher than either morphology or DNA barcodes alone. We explore the use of the DNA barcode for exploring boundaries among taxa, understanding the geographical distribution of cryptic diversity and evaluating the status of purportedly endemic taxa. Finally, we discuss how DNA barcodes may be used to improve field practices and ultimately enhance conservation strategies.

A complete time-calibrated multi-gene phylogeny of the European butterflies

“…Species identities of the chosen sequences for the dataset were validated by blasting the DNA barcode sequences against the Barcode Of Life Database (http://www.boldsystems.org/), which has a good representation of European butterfly species due to a number of barcoding projects implemented in different countries (e.g., Wiemers and Fiedler 2007;Dincă et al 2011;Hausmann et al 2011;Dincă et al 2015;Huemer and Wiesmair 2017;Litman et al 2018). In almost all cases, the sequences came from the same voucher specimen itself.…”

“…Compared to other groups of insects, the phylogenetic relationships of butterflies are reasonably well-known, with robust backbone molecular phylogenies at the subfamily (Wahlberg et al 2005a;Heikkilä et al 2012;Espeland et al 2018) and genuslevel (Chazot et al 2019). In addition, molecular phylogenies also exist for most butterfly families (Campbell et al 2000;Caterino et al 2001;Wahlberg et al 2003;Braby et al 2006;Warren et al 2008;Wahlberg et al 2009;Wahlberg et al 2014;Espeland et al 2015;Sahoo et al 2016;Seraphim et al 2018;Toussaint et al 2018;Allio et al 2020) as well as major subgroups (Wahlberg et al 2005b;Peña et al 2006;Nylin and Wahlberg 2008;Peña and Wahlberg 2008;Wiemers et al 2010;Talavera et al 2013;Peña et al 2015;Condamine et al 2018) and comprehensive COI data at the species level are available from DNA barcoding studies (Wiemers and Fiedler 2007;Dincă et al 2011;Hausmann et al 2011;Dincă et al 2015;Huemer and Wiesmair 2017;Litman et al 2018). Some ecological studies on butterflies have already incorporated phylogenetic information, e.g., on the impact of climate change on abundance trends (Bowler et al 2015;Bowler et al 2017), the sensitivity of butterflies to invasive species (Gallien et al 2017;Schleuning et al 2016) or the ecological determinants of butterfly vulnerability (Essens et al 2017).…”

A complete time-calibrated multi-gene phylogeny of the European butterflies

“…European butterflies are well-studied, ranging from population level analyses 36 to large-scale impacts of global change 37 , with good knowledge on species traits and environmental niche characteristics 38,39 , population trends 40,41 and large-scale distributions 42,43 and are thus well placed for studies in the emerging field of ecophylogenetics 1 .Compared to other groups of insects, the phylogenetic relationships of butterflies are reasonably well-known, with robust backbone molecular phylogenies at the subfamily 44-46 and genus-level 47 . In addition, molecular phylogenies also exist for most butterfly families 48-58 as well as major subgroups [59][60][61][62][63][64][65] and comprehensive COI data on species level are available from DNA barcoding studies [66][67][68][69][70][71] . Some ecological studies on butterflies have already incorporated phylogenetic information, e.g.…”

DNA barcoding of Zygaenidae (Lepidoptera): results and perspectives

“…These activities were undertaken in close cooperation between the Crimean Federal University (Crimea), the Tiroler Landesmuseen, Ferdinandeum (Austria) and the Biodiversity Institute of Ontario at the University of Guelph (Canada) under the framework of the "International Barcode of Life" (iBOL) project. There is another, smaller scale project focused on barcoding Zygaenidae and Papilionoidea, but this recent effort was geographically restricted to Switzerland (Litman et al 2018).…”