Macrofauna Communities in the Mountain Streams of Sri Lanka (Ceylon)

Abstract

The rheophilic macrobenthic communities of the mountainous part of the island of Sri Lanka have been studied based on the material of 170 quantitative stations of small rivers and streams. Thirteen types of communities are described by taxonomic structure (mainly at the genus level) and habitats; similarities with other regions are also shown. A difference between the communities in the lowland (tropical) and highland (subtropical) zones is observed. This paper provides a taxonomic review of the macrofauna sampled and a description of the regional features of its ecology and diversity. Characteristics of the oriental tropical rheophilic communities in comparison with subtropical and boreal Palearctic communities, the influence of altitudinal zonation, the effect of the island on the community structure, and the biogeographic position of Sri Lanka are discussed.