Longitudinal distribution and annual life cycle of the japonicus group of Goerodes(Trichoptera,Lepidostomatidae).

Abstract

In summer, the japonicus group of Goerodes changes from the the upper to the lower stream with overlapping zones in the following sequence : G. complicatus→G. nukabiraensis→G. bipertitus→G. japonicus. In winter, G. satoi is found both upstream and downstream and its lower limit of distribution is lower than for G. complicates. The number of G. nukabiraensis generations is presumed to be three in two years in Hokkaidô. And the annual life cycles of G. bipertitus and G. japonicus are as in G. nukabiraensis.