Southern House Mosquitoes in Collin County, TX | Identification and Control
The southern house mosquito (Culex quinquefasciatus) is the plain brown mosquito that bites in the evening, through the night and in the early morning, and often follows people inside to bite them while they sleep. Texas A&M Mosquito Safari calls it the most important carrier of West Nile virus. It breeds in dirty standing water, from storm drains and neglected pools to a forgotten bucket, and Texas A&M says it rarely flies more than about 1 mile from it.
Getting bitten on the patio after dark, or in bed at night? Our office sits where McKinney, Plano, Frisco and Allen meet, 5 to 10 minutes from most homes in those four cities. Call and we will find the water they are breeding in and the cover they are resting in.
Southern House Mosquito
The southern house mosquito is a medium-sized brown mosquito that feeds at night and breeds in dirty water close to homes. The University of Florida Featured Creatures account says it is found across the southern United States and carries West Nile and St. Louis encephalitis viruses.
Risk Assessment
Choose a row for the full detail- Color
- Plain dull brown, pale bands across the abdomen, no bands on the legs
- Diet
- Females take blood from birds, people and other animals, males drink plant sugars
- Threat level
- High
- Defining behavior
- Bites in the evening, at night and in the early morning, often indoors
- Travel range
- Rarely more than about a mile from where it hatched
- Egg to adult
- 7 to 10 days
- Size
- About 4 millimeters, roughly one sixth of an inch
What Does a Southern House Mosquito Look Like?
A plain, dull brown mosquito with no stripes on its back and no white bands on its legs
The southern house mosquito is the plain one. The Texas A&M Mosquito Safari page on the southern house mosquito describes a delicate, dull brown mosquito with no bands on its legs or its mouthpart, and only light, curved bands across the base of each segment of the abdomen. The University of Florida account puts adults at about 4 millimeters long, with the mouthpart, the middle of the body, the wings and the legs darker than the rest.
The clock gives it away as much as the color. Texas A&M says it is a stealthy biter active in the evening, at night and in the early morning, and that it often comes into homes through unscreened windows or open doors to bite people while they sleep. A high whine by your ear in a dark bedroom is very often this mosquito.
How to identify a southern house mosquito by its plain brown body and unbanded legs, with the dirty standing water it breeds in
- Bites after sunset, through the night and around dawn
- Whining near your ear or bites in bed in a dark bedroom
- A plain brown mosquito with no white stripes anywhere
- Legs with no white bands, unlike the striped daytime biters
- Small floating rafts of eggs or wigglers in dirty, smelly water
- More mosquitoes near a pond, a drain or a pool nobody looks after
Other Names for the Southern House Mosquito
The southern house mosquito is named for where it lives and where it bites. The University of Florida account says it is found across the southern United States, from Virginia to southern California and south through Texas and Florida. Texas A&M shortens it to the house mosquito, for its habit of coming indoors. Health departments often group it with its close relatives as the Culex mosquitoes, the group that carries West Nile virus.
Farther north it meets the northern house mosquito, and the two interbreed where their ranges overlap, which is why some books treat it as a subspecies with a longer scientific name. It is not the Asian tiger mosquito or the yellow fever mosquito, the striped daytime biters in the look-alike table below.
| Name | What it means |
|---|---|
| House mosquito | The short name, for how often it comes indoors. |
| Culex mosquito | The group name for it and its close relatives. |
| Culex quinquefasciatus | The scientific name health departments use. |
| Culex pipiens quinquefasciatus | The name used when it is counted as a subspecies. |
| Asian tiger mosquito | A different species, a striped daytime biter. |
How to Tell a Southern House Mosquito from Other Collin County Mosquitoes
Three mosquitoes do most of the biting around Collin County homes, and the clock and the markings tell them apart. The southern house mosquito is the plain brown one that bites at night, while the two striped ones bite by day.
| Species | Size and Color | Key Feature | Where Found |
|---|---|---|---|
Southern House Mosquito
AKA: House Mosquito
Culex quinquefasciatus
This species
|
Medium and delicate. Dull brown, with no bands on the legs. | Plain with no stripes. Bites in the evening, at night and in the early morning, often indoors. | Breeds in dirty standing water, drains and containers, and flies about a mile from it. |
| Small. Shiny black with white bands on the legs. | One white stripe straight down the middle of the back. Bites by day, especially in shade. | Outdoors in shady shrubs, breeding in small containers within a block or two. | |
| Small. Brown or black with white bands on the legs. | Two thin white lines down the center of the back with Y-shaped white markings beside them. Bites by day and in the evening. | Indoors and outdoors, breeding in containers, staying within a block or two. |
Southern House Mosquito vs Asian Tiger Mosquito
The Southern House Mosquito in Three Numbers
About 1 mile
Texas A&M Mosquito Safari says the southern house mosquito rarely flies more than about 1 mile from its breeding site, so the water feeding it can be several streets away.
Texas A&M Mosquito Safari
100 to 300 eggs
The CDC says a Culex female lays her eggs stuck together in a floating raft of 100 to 300 eggs on fresh or stagnant water.
CDC, About Culex Mosquitoes
24 to 30 hours
The University of Florida Featured Creatures account says southern house mosquito egg rafts normally hatch 24 to 30 hours after they are laid.
University of Florida Featured Creatures
Do Southern House Mosquitoes Bite at Night?
Yes. The University of Florida account calls it a nighttime-active, opportunistic blood feeder that feeds on birds and mammals through the night. The CDC’s page about Culex mosquitoes says they are most active from dusk to dawn. Only the females bite, because they need blood to make eggs, and the CDC’s page about mosquitoes says the usual reaction to a bite is itching and swelling.
Do Southern House Mosquitoes Carry West Nile Virus?
Yes, and this is what sets it apart. Texas A&M Mosquito Safari says the southern house mosquito is thought to be the most important carrier of West Nile virus and St. Louis encephalitis, and the University of Florida account names it the main carrier of St. Louis encephalitis across much of the southern United States. The mosquitoes pick the virus up from infected birds. The CDC’s page about West Nile says the season runs from summer through fall, typically June through October, with diagnoses peaking in late August and early September.
Is West Nile Virus in Collin County?
Yes. The Texas Department of State Health Services weekly arbovirus report for the week ending October 3, 2026 lists 13 mosquito samples that tested positive for West Nile in Collin County and 2 human cases this year. Its 2020 annual report listed 53 positive mosquito samples and 5 human cases in the county.
Are Southern House Mosquito Bites Dangerous?
Most bites are just itchy, and most West Nile infections are mild. The Texas Department of State Health Services West Nile page says about 80 percent of people infected never get sick, about 20 percent get a mild fever, headache and body aches, and only about 1 in 150 develop the severe form that affects the brain and spinal cord. The CDC adds that there is no vaccine or medicine for West Nile in people and that the risk of severe illness rises with age and some medical conditions.
Are Southern House Mosquitoes Dangerous to Dogs and Horses?
The Texas Department of State Health Services says West Nile virus can infect horses as well as people and birds, so horse owners should ask their vet about it. For dogs, the worry is heartworm, which the Food and Drug Administration’s heartworm page says is only spread through the bite of a mosquito. A Tulane laboratory study, Lowrie, 1991, found the southern house mosquito a poor carrier of heartworm, but any mosquito-heavy yard is a reason to keep dogs on the prevention your vet prescribes.
When Southern House Mosquito Activity Needs Fast Action
Fever, Headache or Stiff Neck After Bites
High fever, a stiff neck, confusion or weakness in the weeks after mosquito bites needs a doctor right away. Mention the bites.
Older Family Members Outside After Dark
The risk of severe West Nile illness rises with age. Evenings on the porch in late summer are when protection matters most.
Bites in Bed at Night
Waking up bitten means mosquitoes are getting in through a torn screen, a gap or an open door. Find the gap and close it.
Wigglers in Dirty Standing Water
Wriggling specks in a neglected pool, a pond or a clogged drain are young mosquitoes. Treat or drain it before they fly.
Why Southern House Mosquitoes Get Inside Your House
Because a door or window let them in. Texas A&M Mosquito Safari says that although its favorite hosts are birds, the southern house mosquito often enters homes through unscreened windows or open doors, where it bites people who are asleep. A torn screen, a door propped open at dusk or a gap around a window unit is all it takes. The CDC’s page on preventing mosquito bites says to use screens on windows and doors, repair any holes in them, and use air conditioning where you can.
They are around the house in the first place because they are breeding within flying distance, and for this mosquito that is a wide circle. The water can be a storm drain down the street, a pond on a greenbelt or a pool at a vacant house, not only something in your own yard. It is not a sign of a dirty home.
Where Southern House Mosquitoes Live Around Collin County Homes
By day the adults rest in grass, shrubs and other thick plants where it is cool, dark and humid, according to the CDC. They lay their eggs on standing water that is rich in rotting matter. The CDC lists ponds, lake edges, unkept swimming pools, storm drains and ditches, and smaller containers such as buckets, tires, planters, toys, birdbaths and flowerpots. Texas A&M says this mosquito prefers polluted water.
Southern House Mosquito Pressure Across Collin County
Our mosquito service notes come most often from McKinney, Frisco and Prosper, and the heaviest pressure we see is on lots that back onto a greenbelt, a pond or wooded land. Drainage areas and French drains that hold water are where we find breeding water most.
In Plano and Allen the pattern is the same on a smaller scale, with ponds, fountains and planters the usual sources. Because this mosquito flies about a mile, a neighborhood pond or drainage channel can keep a whole street busy.
Southern house mosquitoes build with the warm spring rains, peak from July into September when West Nile cases also peak, and fade as October cools.
Pattern from Pest Me Off mosquito service records, which climb from March and are busiest July through September, and the CDC West Nile season of June through October.
Why Southern House Mosquitoes Keep Coming Back
How Pest Me Off Gets Rid of Southern House Mosquitoes
Southern house mosquito control is four steps. Spraying the air alone kills only the mosquitoes flying at that moment, so the work goes after the resting cover and the breeding water as well.
Inspect and Identify
A free inspection of the yard. We confirm the species first, since after-dark bites point to the southern house mosquito and daytime bites to the Asian tiger mosquito, and walk the property for every pond, drain and container holding water.
Remove Them at the Source
A treatment across the cool, thick plants where they rest, shrubs, ground cover, fence lines and under decks, and the breeding sites drained or flagged, from the French drain to the neglected fountain.
Install the Barrier
On the same first visit, the Scorched Earth Barrier goes on the perimeter plants, fence lines and eaves. For yards near ponds, creeks and greenbelts, In2Care stations can be added for the water we cannot reach.
Defend All Season
The Skeeter Beater seasonal program returns every 3 weeks, April through October, to renew the barrier and walk the property again for new standing water.
& Other Companies
How to Get Rid of Southern House Mosquitoes Yourself
Most of the work is taking away the water they breed in and keeping them out of the bedroom. The CDC’s page on preventing West Nile puts bite protection first, because there is no vaccine.
Why Some DIY Responses Fail for Southern House Mosquitoes
Most DIY mosquito trouble comes from treating at the wrong time, missing the water that stays wet, or trusting a product nobody has tested.
Treating the Yard Only by Day
This mosquito bites from dusk to dawn and spends the day hidden in thick plants. A quick spray of open lawn at noon never reaches it.
Ignoring the Water That Never Dries
Emptying buckets helps, but a pond, a green pool or a French drain that holds water can raise new mosquitoes every week all summer.
Repellents With No EPA Number
The CDC says to look for the EPA registration number on a repellent label, which means the maker gave the EPA information on how well it works.
Common Southern House Mosquito Questions
What is a southern house mosquito, and what does it look like?
Do southern house mosquitoes bite at night?
Do southern house mosquitoes carry West Nile virus?
Is West Nile virus in Collin County?
Are southern house mosquito bites dangerous?
Are southern house mosquitoes dangerous to dogs?
Why are there mosquitoes in my house at night?
Where do southern house mosquitoes breed?
How far do southern house mosquitoes fly?
How do I get rid of southern house mosquitoes?
Bitten After Dark or in Your Own Bed? We Find Where They Breed.
We find the water they hatch in and the cover they rest in, treat both, and come back through the season before the next wave hatches. Mosquito control across McKinney, Allen, Frisco, Plano, and all of Collin County.

