Advisor: Günther Pass

Master's Defensio - Monday, December 7th 2020

Abstract

Accurate species identification of the Holarctic pill millipedes (Glomerida, Diplopoda) is often a tough challenge. Only a few morphological characters, which can in some cases even vary within species, are used to differentiate the species. Therefore, the pill millipedes appear a particularly suited candidate for additional use of molecular approaches to identify species. However, according to literature reports, the common DNA barcoding is hampered in this taxon by a low success rate, failing several taxa. The present study, which is part of the Austrian Barcode of Life initiative (ABOL), tests the delimitation power of DNA barcodes for Glomerida with several improved methods. For this goal a total of 187 specimens representing 21 species was freshly collected in Austria and France and identified by both morphological and molecular methods. The usually applied workflow for COI-barcoding was improved by using a non-destructive extraction approach (NDE) along with specific primer cocktails. With this optimized protocol, the amplification of the DNA-barcode was increased up to 80% success. In addition to COI, the 28S rDNA D2-D3 fragment proved to be a valuable secondary marker in Glomerida. Overall, the molecular results support current taxonomic units in most cases, but also suggest that current species numbers underestimate real species diversity and that some currently accepted supraspecific taxa are likely to be considered invalid.