Abai, MR

6th International Congress of DipterologyDistribution pattern of crane flies (Diptera: Tipulidae) in theupper and middle reaches of the Shinano River in CentralJapanHirabayashi, K. (1), Y. Fukunaga (1) & T. Mishima (2)(1) Department of Applied Biology, Shinshu University, 3-15-1, Tokida, Ueda, Nagano,386-8567, Japan(2) 3-506, Umegaoka, Tenpaku-ku, Nagoya, Aichi, 468-0004, JapanThis is the first report on crane flies communities captured in summer,2002 by light traps at the upper and middle reaches of the Shinano, Japan’slongest river. A total of 1,096 adults (male 871, female 225) were collected.We identified a total of 13 genera and 23 species belonging to twosubfamilies, i.e., 17 species of Limoniinae (98.3%) and 6 species each ofTipulinae (1.70 %). The most abundant genera was Tipula (4 species),followed by Antocha and Dicronomyia (3 species). The dominant specieswas Antocha (Antocha) bifida (83.3%), followed by Symplecta(Psiloconopa) laudatrix (9.9%). These two species accounted for 93.2% ofthe overall individual numbers. Focusing on the abundance of crane fliesspecies along the river flow from Stations 1 toward Station 4, changes inthe fauna of crane flies and the number of individuals collected were foundto increase, whereas the number of species and the index of diversitydecreased. In the relative frequency of the functional feeding group, thepercentage of shredders decreased, while that of collectors increased.Key Words: crane fly, distribution pattern, Antocha (Antocha) bifida,Shinano River, species diversity index (H’), upper and middle reach∗∗∗∗∗∗∗∗∗∗105