Syrphidae Flower Flies Hover Flies

FIGURE 8.19 Chloropidae, eye gnat {Liohippdatespusio). (A) Adult female; (B) larva. (From Herms, 1939.)

on stems, roots, and root hairs of grasses. The frit fly (iOscinella frit) and the wheat stem maggot (Meromyza americana) are important agronomic pests of grain crops. Other species are saprophytes, feeding mostly on decaying vegetable matter in soils, while a few are predators or gall formers.

Others are known as eye gnats, including Liohippdates species in North and South America and Siphunculina species in Asia. Eye gnats are attracted to humans and other mammals, where they hover about the face, body orifices, and open wounds. The genus Liohippdates (formerly included in the genus Hippelates) occurs throughout much of North America (Sabrosky, 1980). Several species are particularly abundant in some of the sandy-soil regions of the southeastern United States (e.g., Liohippdates pusio and L. pallipes) and irrigated areas of southern California (L, collusor). The larvae feed on decaying organic matter in soil and can be particularly abundant in humus-enriched, cultivated soil or turf in sandy soils. The life cycle is about 2 weeks, and there are multiple generations each year. The adults hover around the head of humans, causing annoyance, especially when they fly into eyes, nostrils, or mouths. They also are commonly found on domestic animals, especially on areas soiled with urine or manure (Greenberg, 1971).

Liohippdates species have been implicated in the mechanical transmission of several organisms that cause diseases in humans and livestock. Treponema- pertenue, the spirochete that causes yaws, has been shown to be transmitted by L. flavipes in Jamaica and other Caribbean and South American locales (Kumm, 1935). Human acute conjunctivitis {pinkeye), caused by several bacterial species, is noticeably more prevalent during outbreaks of Liohippdates in the United States and Siphunculina in the Orient (Dow and Hines, 1957; Greenberg, 1973), Liohippdates species also have been implicated in the spread of the causative organisms of vesicular stomatitis in livestock and streptococcal infections of human skin (Francy et aU, 1988; Taplin et aL, 1967). Brazilian purpuric fever is a fulminating, highly fatal, bacteria) disease of children caused by Haemophilus influenzae biotype aegyptius, which produces acute conjunctivitis in children (Brazilian Purpuric Pever Study Group, 1992; Harrison et al., 1989). L. puruanus and Hippelates neo-proboscideus have been implicated as mechanical vectors of Haemophilus influenzae biotype aegyptius (Tondeila et ai, 1994).

There are 55 genera and about 270 described species in the Nearctic Region (Sabrosky, 1987), Keys to Liohippdates species are provided by Sabrosky (1980). There are no effective area-wide methods for controlling Liohippdates species. Temporary relief from their annoyance is provided by protective head nets and insect repellents containing N, W-diethyl-m-toluamide (DEET).

Emergency Preparedness

Emergency Preparedness

Remember to prepare for everyone in the home. When you are putting together a plan to prepare in the case of an emergency, it is very important to remember to plan for not only yourself and your children, but also for your family pets and any guests who could potentially be with you at the time of the emergency.

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