1. Institute of Zoology, Bulgarian Academy of Sciences, Boulv. Tzar Osvoboditel 1, Sofia 1000, Bulgaria.
2. Johannes Gutenberg Universität, Institut für Molekulargenetik, J.J. Becherweg 32, D-55099 Mainz, Germany.
3. Institute of Zoology, Russian Academy of Sciences, ul. Universitetskaya 1, 199034 St. Petersburg, Russia.
4. Department of Animal and Human Biology, University of Turin, Via Accademia Albertina 13, 10123 Turin, Italy.
5. Faculty of Life Sciences, University of Manchester, Manchester, UK.