Crane fly
Crane flies are large members of the order Diptera, which encompasses all flies, including mosquitoes and gnats. Although they resemble mosquitoes in appearance, crane flies lack the body scales that characterize those insects and are harmless to humans. With approximately 3,300 species found worldwide, excluding polar and desert regions, the United States and Canada host around 1,515 of these species. Crane flies thrive in damp, vegetated habitats near bodies of water, where their larvae, known as leatherjackets, feed on plant roots and stems. Adult crane flies have long, slender bodies, typically brown, and can reach wingspans of up to three inches. Their life cycle includes mating in swarms during the spring and summer, with females laying up to 300 eggs in moist soil. The larvae spend several months underground before emerging as adults to continue the cycle. While they are often abundant, crane flies tend to live alone, and their adult lifespan can vary from a few weeks to several months.
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Crane fly
The family of crane flies contains large members of the order of flies. They are similar to mosquitoes but lack the body scales that mosquitoes have, and adult crane flies are harmless.
Kingdom: Animalia
Phylum: Uniramia
Class: Insecta
Order: Diptera
Infraorder: Tipulomorpha
Superfamily: Various (see below)
Genus: Various (see below)
Species: Various (see below)
The 3,300 species of crane flies are known around the world except in polar and desert regions. Of these, the United States and Canada are home to about 1,515 species. All crane flies belong to the infraorder Tipulomorpha, which is the largest infraorder in the order Diptera. This is the order which contains all the world's flies, mosquitoes, midges, and gnats. Crane flies also belong to the suborder Nematocera, the thread-horned flies.
Crane flies spend their life cycles around bodies of water in a variety of habitats. These include woodlands and grasslands and other damp, shady areas with lots of vegetation. Crane flies have long, tube-like, sucking mouthparts. In these habitats, the larvae, or young, eat the roots and stems of grasses, plants, and crops. The adults lap plant juices, but they eat very little because they are adults for only short periods before they mate and die. Predators of crane flies are such birds as starlings and crows.
The body lengths of adult crane flies range from around 1/2 to one inch (10 to 25 millimeters). The wingspans of some of the largest species may reach three inches (75 millimeters). Their bodies are long and slender and look very similar to those of mosquitoes, but they do not have scales on their bodies as mosquitoes do. Crane flies are usually brown, and some have brown or black markings on their single pair of long, narrow wings. On their thoraxes, or mid-body sections, between their wings they have v-shaped patterns.
Behind the wings of each crane fly is a pair of small, club-like extensions called halteres. These are sensory organs which balance the fly in flight and help it determine speed and direction. Even with these organs, the delicate insects are poor fliers compared to other flies, and they cannot fly in windy weather. The extremely long, thin legs of crane flies enable them to cling to plants, but the insects are awkward and cannot run.
Crane flies often hatch in large numbers, but they generally live alone. Mating often occurs in swarms. The life cycle of crane flies involves three generations of flies which mate three times in two seasons each year. The first mating occurs when adults mate between March and May, and the females lay up to 300 eggs in damp ground. Two or three weeks later, the larvae, or young, hatch. These gray, worm-like maggots are commonly called leatherjackets. They feed and molt, or shed, their skins underground. They then crawl to the surface, form cocoons, and pupate, or transform into their adult forms. These new adults then mate late in summer. Their larvae quickly hatch and become adults which also mate late in summer. The larvae from these flies rest in the ground for several months until the following spring when they hatch and repeat the cycle.
The life spans of crane flies last only a short time after they mate. For some, this is only a few weeks, and for others it is several months. Adult males die before adult females. The complete life cycle of crane flies is one year.
Bibliography
Clark, Caitlin. “What Are Crane Flies?” Texas A&M Today, 12 Apr. 2023, today.tamu.edu/2023/03/28/what-are-crane-flies/. Accessed 12 Apr. 2024.
“Crane Flies (Infraorder Tipulomorpha).” iNaturalist, www.inaturalist.org/taxa/179916-Tipulomorpha. Accessed 12 Apr. 2024.
“Crane Flies - Agricultural Biology.” College of Agricultural Sciences, Colorado State University, agsci.colostate.edu/agbio/ipm-pests/crane-flies/. Accessed 12 Apr. 2024.