A MuseOMICS approach to scrutinise DNA barcode failure

Section Hymenoptera

Testing the causes for taxonomic incongruence patterns in phytophagous Hymenoptera and Orthoptera through hybridization capture using RAD probes

DFG Priority Programm: „Taxon-Omics: New Approaches for Discovering and Naming Biodiversity“  (SPP 1991)

Mono-, para-, and polyphyletic species in some Hymenoptera ‘Symphyta’ (upper graph, for the family Tenthredinidae) and Central European bees (lower graph) (Schmidt et al. 2016).

DNA barcoding has been shown to be highly accurate for the identification of animal species, but some groups defy this approach. Numerous taxa particularly in the ecologically significant phytophagous Hymenoptera and Orthoptera exhibit incongruence between barcode data and traditional taxonomic concepts. Closely related species often form clusters sharing identical or very similar barcodes.

The extensive DNA barcode library and taxonomic expertise with access to reliably identified voucher specimens at the Zoologische Staatssammlung München provides the basis for assessing the genetic structure of otherwise intractable species complexes.

ddRAD and hyRAD genomic sequencing is used to obtain data on the phylogeny of taxa sharing mitochondrial barcodes and to investigate into the sharing of genomic elements by introgression or incomplete lineage sorting in these taxa.

In a multidisciplinary approach we then combine this genomic data with data on morphology, host plants, biogeography, and population structure to determine which factors might be correlated with introgression. Based on our results, we will develop guidelines for the handling of taxa in which barcoding fails, first specifically for the international BOLD barcode database and second as general recommendations for best practice in biodiversity research.

Widespread barcode sharing in the genus Chorthippus (Orthoptera: Acrididae) (Hawlitschek et al. (2016).

References

Hawlitschek, O., Morinière, J., Lehmann, G. U. C., Lehmann, A. W., Kropf, M., Dunz, A., Glaw, F., Detcharoen, M., Schmidt, S., Hausmann, A., Szucsich, N. U., Caetano-Wyler, S. A. and Haszprunar, G. (2016), DNA barcoding of crickets, katydids and grasshoppers (Orthoptera) from Central Europe with focus on Austria, Germany and Switzerland. Mol Ecol Resour. doi: 10.1111/1755-0998.12638

Schmidt, S., Taeger, A., Morinière, J., Liston, A., Blank, S. M., Kramp, K., Kraus, M., Schmidt, O., Heibo, E., Prous, M., Nyman, T., Malm, T. and Stahlhut, J. (2017), Identification of sawflies and horntails (Hymenoptera, ‘Symphyta’) through DNA barcodes: successes and caveats. Mol Ecol Resour, 17: 670–685. doi: 10.1111/1755-0998.12614