1. Department of Integrated Biosciences; Graduate School of Frontier Sciences, the University of Tokyo; Kashiwanoha 5-1-5 Kashiwa Chiba 277-8561 Japan
2. Department of Human Biology and Anatomy; Graduate School of Medicine, University of the Ryukyus; 207 Uehara Nishihara Okinawa 903-0215 Japan
3. The University Museum, the University of Tokyo; Hongo 7-3-1 Bunkyo Tokyo 113-0033 Japan