No-See-Ums (Ceratopogonidae)

Ceratopogonidae, or biting midges (including what are called, in the United States, no-see-ums, midgies, sand flies, punkies, and others), are a family of small flies (1–4 mm long) in the order Diptera. They are closely related to the Chironomidae, Simuliidae (or black flies), and Thaumaleidae.

They are found in almost any aquatic or semiaquatic habitat throughout the world. Females of most species are adapted to suck blood from some kind of host animal. Culicoides, Forcipomyia (Lasiohelea), and Leptoconops suck vertebrate blood. Some Atrichopogon and Forcipomyia are ectoparasites on larger insects. Dasyhelea feed exclusively on nectar. Species in other genera are predatory on other small insects. Larvae are always found in some damp location, such as under bark, in rotten wood, compost, mud, stream margins, tree holes, or water-holding plants (i.e., phytotelmata).

Many of the hematophagic (blood-sucking) species, are pests in beach or mountain habitats. Some other species are important pollinators of tropical crops such as cacao. The blood-sucking species may be vectors of disease-causing viruses, protozoa, and filarial worms. The bite of midges in the genus Culicoides causes an allergic response in equines known as sweet itch. In humans, their bite can cause intensely itchy, red welts that can persist for more than a week. A localized allergic reaction to the proteins in their saliva, the discomfort can be somewhat alleviated by topical antihistamines.

The smaller members of the family are tiny enough to pass through the apertures in typical window screens. Camping tents are often equipped with extra-fine mesh netting, called no-see-um nets, to keep the pests out.