Host utilization by the anuran acanthocephalan Pseudoacanthocephalus bufonis (Echinorhynchidae) on two subtropical islands, southern Japan

Both Iriomote-jima Island and Ishigaki-jima Island belong to the Ryukyu Islands and are located in the subtropical region of Japan. The echinorhynchid acanthocephalan Pseudoacanthocephalus bufonis (Shipley, 1903) was found to parasitize two species of frogs, Fejervarya sakishimensis Matsui, Toda & Ota, 2007 (Dicroglossidae) and Buergeria japonica (Hallowell, 1861) (Rhacophoridae), on Iriomote-jima Island, and one species of toad, Rhinella marina (Linnaeus, 1758) (Bufonidae), on Ishigaki-jima Island. No P. bufonis parasitized Rhacophorus owstoni (Stejneger, 1907) (Rhacophoridae) and Microhyla okinavensis Stejneger, 1901 (Microhylidae) on Iriomote-jima Island. Importance of frogs as the host of P. bufonis differs between host species on this island: F. sakishimensis was very frequently infected and is considered to be the most important host of P. bufonis, but since B. japonica was rarely infected and none of R. owstoni and M. okinavensis was parasitized, the role of these three frogs as the hosts of P. bufonis appears very low. This study also suggests that P. bufonis is native to Iriomote-jima Island.