Aquatic Pests and Critters

See also our photo collection of Aquatic Critters


A lesson in entomological terminology:

Question: When are the immature stages of an aquatic insect a nymph versus a larva? Answer: It depends on whether the insect undergoes complete or incomplete metamorphosis. The life stages of insects undergoing incomplete metamorphosis are egg, nymph, and adult.  The life stages of insects undergoing complete metamorphosis are egg, larva, pupa, and adult.  Among aquatic insects sharing incomplete metamorphosis are mayflies, damselflies, dragonflies, stoneflies, and water bugs (so those insects have nymphs).  Among aquatic insects sharing complete metamorphosis are alderflies, dobsonflies, fishflies, beetles, caddisflies and true flies (so those insects have larvae).


Three mosquito larvae underwater but positioned with their breathing tube--called a siphon--at the surface for air exchange/breathing.
Mosquito Larvae — Photo by Griffin Dill.