1. Ornithological Section, Senckenberg Research Institute and Natural History Museum Frankfurt, Senckenberganlage 25, D-60325 Frankfurt am Main, Germany,
2. Museum of Paleontology, Research Museum Center, University of Michigan, 3600 Varsity Drive, Ann Arbor, Michigan 48108-2228, U.S.A.,
3. Directorate Earth and History of Life, Royal Belgian Institute of Natural Sciences, Rue Vautier 29, B-1000 Brussels, Belgium,