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.

Female deer tick (blacklegged tick) on a green leaf, with a reddish-orange body, dark shield, and black legs, no white markings

Deer tick

Ixodes scapularis

Carries Lyme

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
Full deer tick guide →
Female American dog tick with an ornate off-white and brown mottled shield behind the head

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)
Full american dog tick guide →
Female lone star tick on a green blade of grass, reddish-brown with a single bright white dot in the center of its back

Lone star tick

Amblyomma americanum

Not 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
Full lone star tick guide →
Female brown dog tick, uniform reddish-brown with no distinct markings

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
Full brown dog tick guide →
Female Gulf Coast tick with an ornate silvery patterned shield

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
Full gulf coast tick guide →
Female Asian longhorned tick, small and uniform reddish-brown with no markings

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
Full asian longhorned tick guide →

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.

CountyDeer tickAmerican dog tickLone star tick
Aurora CountyEstablishedEstablishedNot established
Beadle CountyEstablishedEstablishedNot established
Bennett CountyEstablishedEstablishedNot established
Bon Homme CountyEstablishedEstablishedNot established
Brookings CountyEstablishedEstablishedNot established
Brown CountyEstablishedEstablishedNot established
Brule CountyEstablishedEstablishedNot established
Butte CountyEstablishedEstablishedNot established
Campbell CountyEstablishedEstablishedNot established
Charles Mix CountyEstablishedEstablishedNot established
Clark CountyEstablishedEstablishedNot established
Clay CountyEstablishedEstablishedNot established
Codington CountyEstablishedEstablishedNot established
Corson CountyEstablishedEstablishedNot established
Custer CountyEstablishedEstablishedNot established
Davison CountyEstablishedEstablishedNot established
Day CountyEstablishedEstablishedNot established
Deuel CountyEstablishedEstablishedNot established
Dewey CountyEstablishedEstablishedNot established
Douglas CountyEstablishedEstablishedNot established
Edmunds CountyEstablishedEstablishedNot established
Fall River CountyEstablishedEstablishedNot established
Faulk CountyEstablishedEstablishedNot established
Grant CountyEstablishedEstablishedNot established
Gregory CountyEstablishedEstablishedNot established
Haakon CountyEstablishedEstablishedNot established
Hamlin CountyEstablishedEstablishedNot established
Hand CountyEstablishedEstablishedNot established
Hanson CountyEstablishedEstablishedNot established
Harding CountyEstablishedEstablishedNot established
Hughes CountyEstablishedEstablishedNot established
Hutchinson CountyEstablishedEstablishedNot established
Hyde CountyEstablishedEstablishedNot established
Jackson CountyEstablishedEstablishedNot established
Jerauld CountyEstablishedEstablishedNot established
Jones CountyEstablishedEstablishedNot established
Kingsbury CountyEstablishedEstablishedNot established
Lake CountyEstablishedEstablishedNot established
Lawrence CountyEstablishedEstablishedNot established
Lincoln CountyEstablishedEstablishedNot established
Lyman CountyEstablishedEstablishedNot established
Marshall CountyEstablishedEstablishedNot established
McCook CountyEstablishedEstablishedNot established
McPherson CountyEstablishedEstablishedNot established
Meade CountyEstablishedEstablishedNot established
Mellette CountyEstablishedEstablishedNot established
Miner CountyEstablishedEstablishedNot established
Minnehaha CountyEstablishedEstablishedNot established
Moody CountyEstablishedEstablishedNot established
Oglala Lakota CountyEstablishedEstablishedNot established
Pennington CountyEstablishedEstablishedNot established
Perkins CountyEstablishedEstablishedNot established
Potter CountyEstablishedEstablishedNot established
Roberts CountyEstablishedEstablishedNot established
Sanborn CountyEstablishedEstablishedNot established
Spink CountyEstablishedEstablishedNot established
Stanley CountyEstablishedEstablishedNot established
Sully CountyEstablishedEstablishedNot established
Todd CountyEstablishedEstablishedNot established
Tripp CountyEstablishedEstablishedNot established
Turner CountyEstablishedEstablishedNot established
Union CountyEstablishedEstablishedNot established
Walworth CountyEstablishedEstablishedNot established
Yankton CountyEstablishedEstablishedNot established
Ziebach CountyEstablishedEstablishedNot established

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 not 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?
The lone star tick is not established in South Dakota in current CDC county surveillance, but ranges are expanding northward, so this can change. 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.