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American Dog Tick (Dermacentor variabilis)

Detailing the identifying qualities of the American Dog Tick, including physical features and territorial reach.

 Updated: 1/30/2018; Authored By Staff Writer; Content ¬©

  American Dog Tick  
Picture of American-Dog-Tick
Picture of American-Dog-Tick

The American Dog Tick can be found across the continent on dogs, coyotes, bears and any other warm-bodied host that happens to walk by.

Some ticks are notorious for carrying the bacterium that causes Lyme Disease in humans. The American Dog Tick is NOT one of them. It is not entirely harmless though. American Dog Ticks may carry Rocky Mountain Spotted Fever and Tularemia, two serious diseases that can adversely affect humans. Both list a high fever as a symptom, but individuals may vary in a variety of other symptoms connected to these illnesses. Bite wounds associated with Tularemia may form a skin ulcer (gaping wound). Both diseases can be successfully treated with antibiotics when diagnosed early, so it is important to contact a physician immediately if bitten.

Ticks are 8-legged arachnids though they are not spiders. They do not have wings and cannot fly, but they are adept at latching on to clothes, fur and hair that wisps past them within their reach. The American Dog Tick is also known as a Wood Tick. It happens to be spotted most often on dogs coming in from frolicking in the woods, so it has become most familiar as a parasite of that particular animal. The American Dog Tick, however, will feed on just about any animal it can hook its legs onto. After curling their legs around fabric or fur, the tick moves toward the skin. It then crawls to warmer parts of the body like armpits and inner thighs. There, it bites into the flesh while using a numbing agent in its saliva that renders the puncture imperceptible. It is then able to suck the blood from its host unhindered until it is fully engorged and more than double its original size.

Like all ticks, the American Dog Tick has life stages where its physical appearance slightly changes. The coloration changes from nymph stage to adulthood and is different between genders. One might mistake them all for different species. They also look different when they are empty versus engorged. Their wrinkly bodies can inflate like a balloon after a blood meal.

American Dog Tick Information

Category: Mite or Tick
Common Name: American Dog Tick
Scientific Name: Dermacentor variabilis
Other Name(s): Wood Tick

Taxonomy Hierarchy

 Arrow graphic Kingdom: Animalia
  Arrow graphic Phylum: Arthropoda
   Arrow graphic Class: Insecta
    Arrow graphic Order: Ixodida
     Arrow graphic Family: Ixodidae
      Arrow graphic Genus: Dermacentor
       Arrow graphic Species: variabilis

Size, Identifying Tags and Territorial Reach

Size (Adult, Length): Size (Adult, Length): 2 mm to 5 mm (0.078 inches to 0.195 inches)
Identifying Colors: ivory, brown, red, black
Additional Descriptors: tick, blood, round, slow, harmful, biting

North American Territorial Reach (Though Not Limited To): Alabama; Alaska; Arizona; Arkansas; California; Colorado; Connecticut; Delaware; Florida; Georgia; Hawaii; Idaho; Illinois; Indiana; Iowa; Kansas; Kentucky; Louisiana; Maine; Maryland; Massachusetts; Michigan; Minnesota; Mississippi; Missouri; Montana; Nebraska; Nevada; New Hampshire; New Jersey; New Mexico; New York; North Carolina; North Dakota; Ohio; Oklahoma; Oregon; Pennsylvania; Rhode Island; South Carolina; South Dakota; Tennessee; Texas; Utah; Vermont; Virginia; Washington; West Virginia; Wisconsin; Wyoming; Alberta; British Columbia; Manitoba; New Brunswick; Newfoundland and Labrador; Nova Scotia; Ontario; Prince Edward Island; Quebec; Saskatchewan; Mexico

A Note About Territorial Reach: Keep in mind that an insect's reach is not limited by lines drawn on a map and therefore species may appear in areas, regions and/or states beyond those listed above. Insects are driven by environmental factors, food supplies and mating patterns and do not nescessarily work within hard-and-fast territorial lines like we humans do.

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