Deer tick
Ixodes scapularis
Established in Missouri
- Size:
- Small, a sesame seed (nymph: a poppy seed)
- Look for:
- Reddish-orange body, solid dark shield, black legs, no pattern
- Carries:
- Lyme, babesiosis, anaplasmosis, Powassan
Tick Identification in Missouri
The ticks you are most likely to find in Missouri, with photos and the size, color, and markings that tell them apart. Only the deer tick carries Lyme disease. Below the chart, see which types live in your county.
Carries Lyme
American dog tick
Dermacentor variabilis
Established in Missouri
- Size:
- Larger, an apple seed
- Look for:
- Brown with an ornate off-white mottled shield
- Carries:
- Rocky Mountain spotted fever, tularemia (rare)
Lone star tick
Amblyomma americanum
Established in Missouri
- Size:
- Medium, rounded
- Look for:
- Reddish-brown; female has a single white dot on the back
- Carries:
- Ehrlichiosis, STARI, alpha-gal syndrome
Brown dog tick
Rhipicephalus sanguineus
Found nationwide, the one tick that infests homes and kennels indoors
- Size:
- Medium, narrow body that tapers toward the head
- Look for:
- Uniform reddish-brown, no ornate markings
- Carries:
- Rocky Mountain spotted fever, canine diseases
Gulf Coast tick
Amblyomma maculatum
A southern tick spreading north into the mid-Atlantic
- Size:
- Large, bigger than a lone star
- Look for:
- Silvery ornate markings on the shield, no single dot
- Carries:
- Rickettsia parkeri spotted fever
Asian longhorned tick
Haemaphysalis longicornis
A newer arrival, established in the mid-Atlantic and spreading north
- Size:
- Small and plain, often found in large numbers
- Look for:
- Reddish-brown with no markings
- Carries:
- Mainly a livestock threat; human disease risk under study
Rocky Mountain wood tick
Dermacentor andersoni
Not established in Missouri
- Size:
- Larger, an apple seed
- Look for:
- Brown with an ornate off-white and gray marbled shield
- Carries:
- Rocky Mountain spotted fever, Colorado tick fever, tularemia
Pacific Coast tick
Dermacentor occidentalis
Not established in Missouri
- Size:
- Larger, an apple seed
- Look for:
- Brown with a marbled silvery-gray ornate shield
- Carries:
- Pacific Coast tick fever, tularemia
Missouri establishment is shown for the three ticks CDC tracks by county; the others carry a regional range note. Source: CDC tick surveillance (ArboNET Tick Module), 2025. County surveillance is coarse: “not established” is a lack of records, not proof a tick is absent.
Deer, dog and lone star ticks by Missouri county
These are the three ticks CDC maps county by county, not the only ticks in Missouri: the brown dog, Gulf Coast, and Asian longhorned ticks are in the chart above. Tap a county for its daily tick-risk detail.
| County | Deer tick | American dog tick | Lone star tick |
|---|---|---|---|
| Adair County | Established | Established | Established |
| Andrew County | Not established | Established | Established |
| Atchison County | Not established | Not established | Not established |
| Audrain County | Not established | Not established | Not established |
| Barry County | Not established | Reported | Established |
| Barton County | Not established | Not established | Reported |
| Bates County | Not established | Not established | Reported |
| Benton County | Established | Not established | Established |
| Bollinger County | Established | Established | Established |
| Boone County | Reported | Established | Established |
| Buchanan County | Not established | Not established | Not established |
| Butler County | Not established | Reported | Established |
| Caldwell County | Not established | Not established | Established |
| Callaway County | Established | Not established | Reported |
| Camden County | Not established | Not established | Established |
| Cape Girardeau County | Established | Established | Reported |
| Carroll County | Not established | Established | Established |
| Carter County | Not established | Reported | Established |
| Cass County | Not established | Not established | Reported |
| Cedar County | Not established | Established | Established |
| Chariton County | Not established | Not established | Reported |
| Christian County | Not established | Established | Established |
| Clark County | Reported | Not established | Not established |
| Clay County | Not established | Not established | Established |
| Clinton County | Not established | Not established | Not established |
| Cole County | Not established | Reported | Reported |
| Cooper County | Not established | Not established | Established |
| Crawford County | Not established | Established | Reported |
| Dade County | Not established | Established | Established |
| Dallas County | Established | Established | Established |
| Daviess County | Not established | Not established | Not established |
| DeKalb County | Not established | Reported | Not established |
| Dent County | Established | Reported | Established |
| Douglas County | Established | Not established | Established |
| Dunklin County | Not established | Established | Not established |
| Franklin County | Not established | Not established | Established |
| Gasconade County | Established | Not established | Established |
| Gentry County | Not established | Established | Established |
| Greene County | Established | Established | Established |
| Grundy County | Not established | Not established | Not established |
| Harrison County | Not established | Not established | Not established |
| Henry County | Not established | Not established | Established |
| Hickory County | Not established | Reported | Established |
| Holt County | Not established | Not established | Established |
| Howard County | Not established | Not established | Reported |
| Howell County | Established | Not established | Reported |
| Iron County | Not established | Not established | Established |
| Jackson County | Not established | Not established | Established |
| Jasper County | Established | Not established | Reported |
| Jefferson County | Not established | Not established | Established |
| Johnson County | Established | Established | Established |
| Knox County | Not established | Not established | Not established |
| Laclede County | Established | Established | Established |
| Lafayette County | Not established | Not established | Established |
| Lawrence County | Not established | Established | Established |
| Lewis County | Not established | Not established | Not established |
| Lincoln County | Reported | Not established | Established |
| Linn County | Not established | Reported | Established |
| Livingston County | Not established | Not established | Not established |
| Macon County | Not established | Reported | Reported |
| Madison County | Not established | Not established | Established |
| Maries County | Not established | Not established | Not established |
| Marion County | Not established | Not established | Established |
| McDonald County | Not established | Reported | Established |
| Mercer County | Not established | Not established | Not established |
| Miller County | Reported | Established | Established |
| Mississippi County | Not established | Not established | Not established |
| Moniteau County | Not established | Not established | Not established |
| Monroe County | Not established | Not established | Established |
| Montgomery County | Reported | Not established | Not established |
| Morgan County | Not established | Not established | Reported |
| New Madrid County | Reported | Not established | Not established |
| Newton County | Reported | Established | Established |
| Nodaway County | Not established | Established | Established |
| Oregon County | Not established | Not established | Not established |
| Osage County | Established | Not established | Not established |
| Ozark County | Not established | Reported | Established |
| Pemiscot County | Not established | Reported | Not established |
| Perry County | Not established | Not established | Reported |
| Pettis County | Not established | Not established | Not established |
| Phelps County | Not established | Not established | Established |
| Pike County | Not established | Not established | Not established |
| Platte County | Not established | Not established | Reported |
| Polk County | Not established | Established | Established |
| Pulaski County | Established | Reported | Established |
| Putnam County | Not established | Not established | Not established |
| Ralls County | Not established | Not established | Reported |
| Randolph County | Not established | Reported | Not established |
| Ray County | Not established | Not established | Not established |
| Reynolds County | Not established | Not established | Established |
| Ripley County | Not established | Not established | Established |
| Saline County | Not established | Established | Established |
| Schuyler County | Not established | Not established | Not established |
| Scotland County | Not established | Reported | Not established |
| Scott County | Reported | Established | Reported |
| Shannon County | Not established | Not established | Established |
| Shelby County | Not established | Reported | Not established |
| St. Charles County | Established | Not established | Established |
| St. Clair County | Reported | Not established | Established |
| St. Francois County | Not established | Not established | Reported |
| St. Louis County | Reported | Established | Established |
| St. Louis city | Not established | Not established | Reported |
| Ste. Genevieve County | Not established | Not established | Reported |
| Stoddard County | Established | Established | Established |
| Stone County | Established | Reported | Established |
| Sullivan County | Not established | Not established | Not established |
| Taney County | Established | Established | Established |
| Texas County | Established | Established | Reported |
| Vernon County | Not established | Not established | Established |
| Warren County | Not established | Not established | Established |
| Washington County | Not established | Reported | Established |
| Wayne County | Established | Established | Established |
| Webster County | Established | Established | Established |
| Worth County | Not established | Established | Established |
| Wright County | Not established | Established | Established |
Lone star ticks and alpha-gal syndrome
The lone star tick is established in Missouri in 63 of 115 counties (see the table above). Its bite can cause alpha-gal syndrome, an allergy to red meat.
Do not overlook the tiny ones
Nymph deer ticks are the size of a poppy seed and cause most Lyme cases in Missouri because they are so easy to miss. When you check for ticks, look for the small ones too, especially in June and July.
Frequently asked questions
- What types of ticks live in Missouri?
- Missouri has the deer tick (blacklegged tick), which carries Lyme disease and is established across the state; the American dog tick, which is established; and the lone star tick, which is established and causes alpha-gal syndrome. County-level presence is shown in the table above.
- Which Missouri tick carries Lyme disease?
- The deer tick, also called the blacklegged tick, is the tick that spreads Lyme disease in Missouri. The American dog tick and lone star tick do not carry Lyme, though they can transmit other illnesses.
- Are there lone star ticks in Missouri?
- Yes. The lone star tick is established in Missouri, in 63 of the state's 115 counties (Adair County, Andrew County, Barry County and more, listed in the table above). It causes alpha-gal syndrome, a red-meat allergy.
- How can I tell these ticks apart?
- Use size, color, and legs. The deer tick is small with a reddish-orange body, a solid dark shield, and black legs. The American dog tick is larger and brown with an ornate off-white mottled shield. The female lone star tick has a single white dot on her back. The chart above shows each one.