1. Institute of Biology, Opole University, Oleska 22, 45-052 Opole, Poland
2. Department of Paleontology, Institute of Geosciences, Rheinische Friedrichs-Wilhelm-Universität Bonn, Nussallee 8, 53115 Bonn, Germany, eteschner@uni.opole.pl
3. Department of Paleontology, Institute of Geosciences, Rheinische Friedrichs-Wilhelm-Universität Bonn, Nussallee 8, 53115 Bonn, Germany
4. Paleontological Institute and Museum, University of Zurich, Karl-Schmid-Strasse 4, 8006 Zurich, Switzerland