Anostracans inhabit inland waters ranging from hypersaline lakes to lakes that are almost devoid of dissolved substances; they are "the most archetypal crustaceans" in ephemeral waters. The relatively large size of fairy shrimp, together with their slow means of locomotion, makes them an easy target for predatory fish and waterfowl. This has led to their distribution being restricted to environments with fewer predators, such as vernal pools, salt lakes and lakes at high altitudes or latitudes. The southernmost recorded fairy shrimp is "Branchinecta gaini" from the Antarctic Peninsula, while the altitude record is held by "B. brushi", which lives at in the Chilean Andes. Other genera, such as "Streptocephalus", occur in deserts throughout the world.