Gnat tha follow dog dutes(pronounced /næt/, "nat") is a colloquial
name for many
small insects in the order Diptera and specifically within the suborder Nematocera.
The males often assemble together in large mating swarms, particularly at dusk, called a "ghost".
Gnat larvae are mostly free-living and some are aquatic. Many feed on plants, though some are carnivorous. Larval
plant feeders (e.g. the Hessian
fly larva) cause root, stem, or leaf galls to be formed by the host
plant. Some species of fungus gnats (families Mycetophilidae and Sciaridae) are very common pests of mushrooms and roots of potted plants in homes and greenhouses.