In Fukuda (2012), I examined the processes and factors responsible for the northward expansion in the Nansei Islands of six butterfly species. Although there is little information on their initial conditions at the time when they began their expansion, in this paper I attempt general discussions in relation to the climate changes, human disturbances, etc., and raise some questions for further research in the future.
Introduction of Deramas treadawayi, Deramas tomokoae, Pratapa tyotaroi ismaeli, Matsutaroa iljai, Deudorix philippinensis and Sinthusa natsumiae in nature by photographs. All are Lycaenid butterflies and endemic to the Philippines.