Map of Japan with sampling localities (red circles), created using Google Maps.

Taxonomic lists of the Japanese elaterids have been published by some authors [11–13], and the number of species listed has steadily increased (Table 1). At present, approximately 130 elaterid genera and 770 species have been recorded in Japan (reviewed in Ôhira, 2013 [3]), although the most updated species list was not published with this review. This number of elaterid species in Japan is comparable with that of the whole Nearctic region (965 species) [2] and much larger than that of the British Islands (73 species) [14], which are as large as the Japanese Islands. These numbers highlight the high elaterid biodiversity in Japan. Adult elaterids are relatively common in Japan. They are often collected in various traps during environmental impact statement research and thus appear as significant members in the prefectural lists of wild insects. For example, Elateridae constitutes 5.1% and 4.9% of the beetle species collected in Tochigi [15] and Okayama [16] prefectures, respectively.