1. Graduate School of Life and Environmental Sciences, Kyoto Prefectural University, Shimogamo, Kyoto 606-8522, Japan
2. Japan Collection of Microorganisms, RIKEN BioResource Center, Tsukuba, Ibaraki 305-0074, Japan
3. Research Institute of Tropical Ecology, Libreville, Bp 13354, Gabon
4. Graduate School of Veterinary Medicine, Kagoshima University, Kagoshima 890-0065, Japan
5. Graduate School of Science, Kyoto University, Kitashirakawa, Kyoto 606-8502, Japan