1. Meguro Parasitological Museum, Shimomeguro, Meguro-ku, Tokyo 153-0064, Japan.
2. Department of Parasitology, Asahikawa Medical University, Asahikawa, Hokkaido 078-8510, Japan.
3. Laboratory of Veterinary Parasitology, Faculty of Veterinary Medicine, Okayama University of Science, Ikoinooka 1-3, Imabari 794-8555, Japan.
4. Ibaraki Nature Museum, 700 Osaki, Bando, Ibaraki 306-0622, Japan.
5. The Malacological Society of Japan, 4378-3 Shimogo, Kasama, Ibaraki 319-0202, Japan.