5 common species of flies

5 common species of flies

If you see a winged invader in your home and call it a fly, you could be wrong.

The name fly is strictly applicable to members of Diptera. Diptera members number in the thousands (120,000+ species), leading as one of the largest insect orders in the world. These winged invaders are small, soft bodied, and have one set of wings and one set of halteres.

Top five species of flies, their lifespan, & their lifecycle

Though there are many more species of popular flies, including the stable fly, the blow fly, the drain fly, and the flesh fly, these are the most common flies that readers inquire about.

1. Housefly

These little miscreants walk on vertical window panes and hang upside down on your ceiling. Beneath the little claws on their feet, they have tinier glandular pads that produce a secretion, a secretion that allows them to stick (just enough) upside down, but claws that allow them to then become unstuck. Fly eggs look like whitish slender grains of rice. The female deposits more than 100 of these house fly eggs at a time, which will hatch in 12 to 24 hours. She does this multiple times, producing between 600 to 1,000 eggs in her lifetime.


The house fly's life cycle is short, but not so short that they (as one multiples quickly) can’t quickly cause a housefly infestation if left uncontrolled. Their lifespan is generally 15 to 30 days.

Life cycle

The life cycle of a house fly includes the egg stage, the larvae stage, the pupa stage, and the adult stage. 


2. Mosquito

The word "mosquito" is Spanish and Portuguese for "little fly." These nuisances transmit serious disease, including yellow fever, Zika fever, malaria, filariasis, and dengue. Mosquitoes are attracted to you (or a host animal) by moisture, lactic acid, (which is formed when the body breaks down carbohydrates to use for energy when oxygen levels are low, like during intense exercise), carbon dioxide, body heat, and movement.


The lifespan of a mosquito is different for a male and a female. A male mosquito lives for approximately 6-7 days. A female mosquito lives for approximately 6 weeks, but can live up to 5 months or longer as long as she has an adequate food supply.

Life cycle

Females lay around 100 eggs on the inner, wet walls of containers (whether a bowl, a barrel, or a vase) with water. In most species, the females require a blood meal in order to mature their eggs. These eggs hatch into wriggers, which swim with a jerking, wriggling movement. After molting, they become pupae. Pupae remain in the water, breathing by means of tubes on the thorax, until they become adult flying mosquitoes. They then leave the water and begin to mate.

3. Horse fly

These large, stout, fast, agile, flies, usually found around streams, marshes, and wooded areas, are sometimes referred to as green-headed monsters, with their large metallic or iridescent eyes and ferocious bites. The males can’t bite, but the females sure do. Their mouthparts are like tiny steak knives, used for tearing into the flesh and then lapping up the blood. A horse fly bite, as I'm sure you can guess, is very painful, and, when abundant, can suck more than 3 ounces of blood from a host in a day. 

In the world of flies, the size of a horse fly can be giant, depending on the species. The Tabanus Sudeticus, known as the giant dark horse fly, is heavy and measures around 25 mm in length, which is just shy of an inch. Horse flies, like mosquitoes, are attracted by carbon dioxide, movement, and body heat. They are also attracted to shiny surfaces.


A horse fly can expect to live 30-60 days.

Life cycle

In the fall, the females deposit long, flat-black eggs, in clusters, on grass. In the winter, the eggs hatch and turn into larvae. In the spring, these larvae develop into pupae and then emerge as adults by June.

4. Gnat

Gnats are slender, long-legged, tiny (less than ¼ of an inch long) mosquito-like scoundrels that are attracted to moisture, which is where they feed, breed and quickly reproduce. Some species have tough skin-piercing scissor-like mouthparts and bite; others have softer mouthparts and can’t bite. Of these biting species, it’s only the females that bite, as they need a blood meal to reproduce. The males resort to feeding on plant nectar.


Gnats are difficult to scientifically define, as the word "gnat" is actually a loose casual term, rather than a specific term defining classification. Gnats generally refer to a group of small flies that bite (although there are non-biting species as well) and annoy people. These may include the fungus gnat, fruit fly, drain gnats, phorid fly, and blow fly.

If you find gnats in your home, they’re there because of their attraction to food spillage, open or overflowing garbage cans, and moisture—moist potting soil, a puddle on your kitchen floor, a leaky pipe under your sink, or condensation around windows and vents. Too, there could be an extended gnat family living in your sink drain, as it provides the basic gnat necessities: food, water, shelter, and a breeding site.


A gnat’s lifespan is very short. Twenty-eight days is all it takes, from egg to adult (and reproduction). Thus, generations can overlap and mature in the same location. Once an adult, a gnat’s life is basically over, as adults only live for approximately 7 days.

Life cycle

Females lay their eggs (numbering around 200) below the ground. They prefer high temperature environments, which make greenhouses, garden centers, and plants their breeding grounds of choice. These eggs hatch and pupate in the soil, emerging from the dirt that bore them until they are their complete winged, adult, reproductive selves.

5. Fruit fly

Fruit flies are among the most common pests in the world. Whether tromping through the grasslands of North Dakota, hiking in the Bridger-Teton National Forest in Wyoming, mucking in the Everglades of Florida, or vacationing on the West Coast, you’re bound to come across these small flies hovering near plants. They’re particularly abundant in the spring and summer months and enjoy spending their winters secluded in warm spots.

Are you curious as to what fruit flies eat? You may think that all that they’re after are those rotting bananas that you should have gotten rid of long ago.

What is the difference is between fruit flies and gnats? They’re both tiny and annoying, but their attractions (and how to get rid of them) are not.

Do you know whether or not fruit flies will die off on their own or if you have to be proactive to get rid of them? Their reproductive cycle is wicked fast. I wouldn’t wait too long to find out.



The entire lifespan lasts between 25-50 days.

Life cycle

Females wait to be enticed by their male counterparts. The males serenade the females with a courtship song, vibrating their wings to create an alluring tune. If the female accepts, the couple spends 15-20 minutes copulating. The female then lays her eggs in organic material (rotting fruit, meat, etc.). These eggs turn into larvae, pass through a few molts, surrounds itself with a hard shell, and transforms into an adult.

How to deal with a fly infestation

Whether you have small fruit flies hovering over your fruit bowl, large horseflies on your patio, tiny gnats in the drain in your kitchen sink, mosquitoes buzzing in your ear, or large house flies entering through an open door, there are a few proven methods to get rid of these unwelcome visitors.

Dr. Killigan cares about your peace of mind and restoring peace to your home.

Infestation of fruit flies

For a fruit fly infestation, a simple DIY trap will do: Fill a bowl with apple cider vinegar, sealing it tight with plastic wrap and a rubber band. Then, using a toothpick, poke tiny holes in the plastic. The vinegar will attract the fruit flies. The plastic wrap will keep them trapped. Don’t worry about those intruders flying back out through those tiny holes. They aren’t that smart. (Their brains are very, very small.)

The trap will get rid of the adults. Dr. Killigan’s Six Feet Under Non-Toxic Indoor Insect Spray will get rid of the eggs. Wipe out the bottom of your fruit bowls, the insides of your garbage cans and recycle bins, and anywhere where you’ve seen fruit fly activity with this kill-on-contact non-toxic spray. Spray, rest, repeat. Let Dr. Killigan do the dirty work.

Infestation of horse flies

For a horse fly infestation, the best means of dealing with these large flies is to drain their breeding grounds, clean up after your pets, burn a citronella candle if you’re having a backyard barbecue, and make sure your outdoor trash bins have lids that fit snugly.

Infestation of gnats

For a gnat infestation, a DIY trap will do: Mix half a cup of warm water with two tablespoons of apple cider vinegar, one tablespoon of sugar, and about six drops of liquid dish soap. Pour this into a shallow bowl, mix, and go about your business. Gnats will die (literally) for this sugary treat.

Because gnats are attracted to food spillage and open or overflowing garbage cans, it’s important to do a very thorough cleaning of these areas. I recommend a deep cleaning and good spraying of Six Feet Under in your garbage cans and recycle containers.

Infestation of mosquitoes


To prevent mosquito bites, wear long-sleeved shirts, long pants, and tall socks. To take it a step further, tuck your shirts into your pants and your pants into your socks. You may feel a bit silly, but feeling silly is preferable to getting bit, itchy, and uncomfortable.

Infestation of houseflies

For a housefly infestation, Dr. Killigan has you covered. The Fly Inn is an attractive, discreet, fly hotel where the guests never leave. Our Leather Fly Swatter, with its fiberglass core shaft, leather grip, and dual-sided leather flap, is promised to be the last flyswatter you’ll ever need. Enjoy its smack-down power.

How to prevent a fly infestation

To prevent these flying black bugs from becoming guests in your home, ensure that sticky messes are cleaned up, food is not left out on your counters, your dish drain is clean, your windows, doors and house vents are sealed properly and free from holes. Use a garbage can with a tight-fitting lid and take it out as soon as it is full. If you have a pet, make sure to clean the pet bowl.

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