Arachnids are presented by several species of spiders and mites.
In freshwater reservoirs decapods live - shrimps compete successfully to fishes. From shrimps the endemic family of Antarctic false crayfishes leading terrestrial way of life descended. The fauna of ground-dwelling crabs is poor: only at the coast and on islands of Subantarctic there are some kinds of them. In fresh waters there are also representatives of isopods.
Gastropod fauna is very poor and includes descendants of sea kinds adapted for life in fresh water. Also bivalves live in rivers.