1. Department of Invertebrate Zoology, Swedish Museum of Natural History, Stockholm, Sweden; E-mail: ulf.jondelius@nrm.se
2. Department of Systematic Biology, Evolutionary Biology Centre, Uppsala University, Uppsala, Sweden; E-mail: andreas.wallberg@gmail.com
3. University of Maine, School of Biology and Ecology, Orono, ME, USA
4. Zoological Institute, Russian Academy of Sciences, Sankt-Petersburg, Russia