Comparative Insect Faunas between Ganghwado and Six Others Islands of West Coastal in Incheon, Korea

This study was conducted to investigate the biogeographic characteristics of the insect faunas of the seven islands of the west coast of Incheon, Korea, using a quantitative analysis method. The faunal similarity was examined using the Bray & Curtis similarity. The obtained similarity value matrix was examined with cluster analysis using the UPGMA method. The recorded number of each species in the areas was 1,001 from 12 orders and they were distributed on the seven islands surveyed. Among the surveyed islands, Seokmodo had the highest number of species with 497, while Yeonpyeongdo had the lowest with 136 species. The species composition of insects reported in Ganghwado was 309 species belonging to seven orders. The similarity values between the seven localities investigated ranged from 24.907 (Gyodongdo to Yeonpyeongdo) to 49.899 (Baengnyeongdo to Ganghwado). That is, the species composition of Baengnyeongdo (47.90%) was similar to that of Ganghwado, while it was different from that of Yeonpyeongdo (25.28%). The cluster analysis using a similarity index shows that all the islands in these areas can be divided into 3 groups at the level of 30.97%.