The insect fauna in Ryukyu Ruddy Kingfisher nests was investigated on Iriomote-jima, Ishigaki-jima and Miyako-jima Is., Okinawa, Japan. Kingfishers on Iriomote-jima and Ishigaki-jima Is., where Takasago termites which make ball-like nests on trees are distributed, often dig nesting holes in the termite nests, but they excavate holes in decayed trees on Miyako-jima I. where the termites are not present. Moths belonging to the family Tineidae were found to be the main symbiotic insects in the nests, and eight moth species, including two species considered to be undescribed or newly recorded species from Japan, were confirmed. The differences in moth faunas of the kingfisher nests between the three islands are discussed.
