Abstract: 【Abstract】 The salivary glands were exposed and isolated from the larvae of Simulium quinquestriatum and stained in carbol fuchsin, squashed between slide and coverslide. Slides were examined and photographed under microscope to measure the polytene chromosomes. Systematic analysis was made. Results indicated that the number of the polytene chromosomes of both isolates is three. The main characteristic chromosomal structures are homologized. Only the banding types of ⅡL are different.

Key words: Simulium quinquestriatum, Polytene chromosomes, Ideogram