From water to air: we only know many flying insects as adults, but many of them have their first life stages in the water. The larvae of mayflies, for example, spend almost a year in the shallow shore zones of standing waters before they come ashore for a few days as adult flies. These so-called semi-aquatic insects are an important food source for animals in the water and on land and are used as bioindicators to assess water quality and the state of freshwater ecosystems.
