DISTRIBUTION CHARACTERISTICS OF AQUATIC INSECTS IN SOUTHERN HAI VAN AREA, DA NANG CITY

Abstract

The species composition and altitudinal distribution of aquatic insects were investigated from the Southern Hai Van area, Da Nang city. Five sites (75 m, 150 m, 200 m, 300 m and 400 m above sea level) from upper to lower reaches of the stream were sampled from February 2017 to March 2018. The results showed a total of 43 species of 29 genera and 13 families. The Ephemeroptera (Mayflies) was the most diversified with 25 species (58.14% of total species), 15 genera (51.72% of total genera), 4 families (30.77% of total families). The second was the Trichoptera (Cadisflies) with 10 species (23.26%), 8 genera (27.59%), and 5 families (38.46%); followed by Plecoptera (Stonflies) with 8 species (18.60%), 6 genera (20.69%), 4 families (30.77%). The number of collected species decreases with deceased altitudes: 29 at 400 m; 30 at 300 m; 21 at 100 m; 16 at 75 m.