Deer tick
Ixodes scapularis
Established in South Dakota
- 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 South Dakota
The ticks you are most likely to find in South Dakota, 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 South Dakota
- 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 South Dakota
- 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 South Dakota
- 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 South Dakota
- Size:
- Larger, an apple seed
- Look for:
- Brown with a marbled silvery-gray ornate shield
- Carries:
- Pacific Coast tick fever, tularemia
South Dakota 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 South Dakota county
These are the three ticks CDC maps county by county, not the only ticks in South Dakota: 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 |
|---|---|---|---|
| Aurora County | Not established | Not established | Not established |
| Beadle County | Not established | Not established | Not established |
| Bennett County | Not established | Not established | Not established |
| Bon Homme County | Not established | Established | Not established |
| Brookings County | Reported | Established | Not established |
| Brown County | Not established | Established | Not established |
| Brule County | Not established | Not established | Not established |
| Butte County | Not established | Reported | Not established |
| Campbell County | Not established | Not established | Not established |
| Charles Mix County | Not established | Established | Not established |
| Clark County | Not established | Reported | Not established |
| Clay County | Established | Established | Established |
| Codington County | Reported | Reported | Not established |
| Corson County | Not established | Reported | Not established |
| Custer County | Not established | Not established | Not established |
| Davison County | Not established | Established | Not established |
| Day County | Established | Established | Not established |
| Deuel County | Not established | Established | Not established |
| Dewey County | Not established | Not established | Not established |
| Douglas County | Not established | Not established | Not established |
| Edmunds County | Not established | Not established | Not established |
| Fall River County | Not established | Reported | Not established |
| Faulk County | Not established | Not established | Not established |
| Grant County | Not established | Reported | Not established |
| Gregory County | Not established | Reported | Not established |
| Haakon County | Not established | Reported | Not established |
| Hamlin County | Not established | Reported | Not established |
| Hand County | Not established | Reported | Not established |
| Hanson County | Not established | Not established | Not established |
| Harding County | Not established | Not established | Not established |
| Hughes County | Not established | Reported | Not established |
| Hutchinson County | Not established | Not established | Not established |
| Hyde County | Not established | Not established | Not established |
| Jackson County | Not established | Established | Not established |
| Jerauld County | Not established | Not established | Not established |
| Jones County | Not established | Not established | Not established |
| Kingsbury County | Not established | Established | Not established |
| Lake County | Not established | Reported | Not established |
| Lawrence County | Not established | Established | Not established |
| Lincoln County | Established | Established | Not established |
| Lyman County | Not established | Not established | Not established |
| Marshall County | Reported | Established | Not established |
| McCook County | Not established | Established | Established |
| McPherson County | Not established | Not established | Not established |
| Meade County | Not established | Established | Not established |
| Mellette County | Not established | Not established | Not established |
| Miner County | Not established | Not established | Not established |
| Minnehaha County | Not established | Established | Reported |
| Moody County | Not established | Not established | Not established |
| Oglala Lakota County | Not established | Reported | Not established |
| Pennington County | Not established | Reported | Not established |
| Perkins County | Not established | Reported | Not established |
| Potter County | Not established | Not established | Not established |
| Roberts County | Reported | Established | Reported |
| Sanborn County | Not established | Not established | Not established |
| Spink County | Not established | Reported | Not established |
| Stanley County | Not established | Reported | Not established |
| Sully County | Not established | Not established | Not established |
| Todd County | Not established | Not established | Not established |
| Tripp County | Not established | Reported | Not established |
| Turner County | Not established | Not established | Not established |
| Union County | Established | Established | Established |
| Walworth County | Not established | Not established | Not established |
| Yankton County | Not established | Established | Established |
| Ziebach County | Not established | Reported | Not established |
Lone star ticks and alpha-gal syndrome
The lone star tick is established in South Dakota in 4 of 65 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 South Dakota 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 South Dakota?
- South Dakota 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 South Dakota tick carries Lyme disease?
- The deer tick, also called the blacklegged tick, is the tick that spreads Lyme disease in South Dakota. The American dog tick and lone star tick do not carry Lyme, though they can transmit other illnesses.
- Are there lone star ticks in South Dakota?
- Yes. The lone star tick is established in South Dakota, in 4 of the state's 65 counties (Clay County, McCook County, Union 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.