Nymphulinae

The Nymphulinae are a subfamily of moths within the family Pyralidae. These moths are characterized by their aquatic larvae, which possess tracheal gills that allow them to live in still or running fresh water.1

In entomology, a nymph is the sexually immature stage of insects that undergo incomplete metamorphosis, such as grasshoppers and cockroaches. Nymphs typically resemble the adult form, with wings developing externally after several molts. This is distinct from true larvae, which are the immature forms of insects with complete metamorphosis, like butterflies and beetles. Aquatic young of insects like dragonflies and mayflies are sometimes called naiads, and they possess gills and other adaptations for aquatic life before emerging as winged adults.2