D. magna is a key species in many lentic habitats. It can be found in lakes and in shallow ponds rich in organic matter sediment.[9] Numerous natural predators are known and can lead to plastic phenotypic responses. In the presence of kairomones Daphnia develop conspicuous protective structures as an elongated spine and a large body size.[10] It is an important primary consumer and, also, prey of many planktivorous fishes.[11] Other invertebrate predators are the larvae of the phantom midge Chaoborus and hemipterans (Notonecta) and Triops. The large size of the adults protects them from predation from some planktivorous invertebrates