Jekyll and Hyde species?
Taxonomic confusion from morphological evolution
Many cladoceran species exhibit multiple extreme morphologies that are often associated with differing environments or seasons. Here a typical specimen of Daphnia longiremis from Salmon Lake Alaska (a habitat with abundant planktivorous fish) is shown with Daphnia longiremis from a nearby pond with abundant copepod predators. It is unknown for many cases if the source of variation is parallel speciation, morphological divergence despite gene flow, or phenotypic plasticity. Each of these processes may have contributed to taxonomic confusion in Cladocera.
