|Budget Amount *help
¥2,000,000 (Direct Cost : ¥2,000,000)
Fiscal Year 1995 : ¥600,000 (Direct Cost : ¥600,000)
Fiscal Year 1994 : ¥700,000 (Direct Cost : ¥700,000)
Fiscal Year 1993 : ¥700,000 (Direct Cost : ¥700,000)
1) Tettigoniids of the genus Metrioptera are widely distributed in the Japanese Islands. The Far Eastern species of the genus belong to Eobiana, one of its hitherto known subgenera, based on the present study. However, Eobiana should be lifted upto a genus level, because of showing its different morphology in female subgenital plate and male titillator. From Far East including the Japanese Islands, two species, japonica and engerhardti, arn known in the genus, and the latter species includes two subspecies, the nominotypical species from the Far Eastern area of the Continent and subtropica from Hokkaido, Honshu and Shikoku, Japan. All of these taxa were fully redescribed, together with figures.
2) Leptoteratura albicorne, one of small tettigoniids from Honshu, belongs to a different species group from the taiwana species group of the Ryukyu Islands, because of bearing the most specified male cerci. It has been surmised that this species may have originally derived from the Chinese stock (Yamasaki, 1982). In the present study, the type specimen of Xiphidiopsis omeiensis having the possibility that it belongs to Leptoteratura was examined with additional materials. It revealed the fact that omeiensis was a synonym of L.albicornis and additional specimens were of the species. This means the above-mentioned supposition is correct.
3) The introducing routes of two species of Eobiana and Leptoteratura albicornis into the Japanese Islands are as follows : Eobiana has two route, north and south, in which engerhardti is from north route by way of Hokkaido to Honshu and Shikoku and japonica from south by way of the Korean Peninsula to Kyushu and Honshu. However, there is a possibility that japonica was derived from the ancestral species of engelhardti in Honshu.