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Black-Legged Tick (Ixodes scapularis)

Detailing the identifying qualities of the Black-Legged Tick, including physical features and territorial reach.

 Updated: 2/8/2018; Authored By Staff Writer; Content ¬©

  Black-Legged Tick  
Picture of Black-Legged-Tick
Picture of Black-Legged-Tick Picture of Black-Legged-TickPicture of Black-Legged-TickPicture of Black-Legged-TickPicture of Black-Legged-TickPicture of Black-Legged-Tick

The Black-Legged Tick is an arachnid with a bite that can do more damage than most spiders.

The Black-Legged Tick is a carrier of Lyme disease and transmit it to humans. This arachnid picks up the Lyme disease-causing bacteria by feeding on mice and deer. It is during feeding that the Lyme Disease-causing bacteria can pass from the tick into the host (deer, human, mouse, etc.). The longer the tick has to feed, the greater the opportunity for the bacteria to transfer and infect. Because of this, the Center for Disease Control in the U.S. encourages people who finds ticks on themselves to remove them as soon as possible. Because the infecting vector may be in the feeding tube, even if the tick is crushed or decapitated, it may still transmit the bacteria. Complete removal of the tick's head and feeding tube within 24 hours of the initial bite can reduce possible infection according to the CDC. If you have been bitten by a Black-Legged Tick, seek medical attention and get tested for Lyme Disease. Early diagnosis of Lyme Disease improves treatment effectiveness and symptom management.

Commonly found in the Eastern United States, the Black-Legged Tick adult sits on low plant vegetation (shrubs, ferns, flowers) until a potential host animal walks by. With its front legs outstretched, it clings onto whatever it can: fur, tail, clothing, etc. It then crawls to to warmer parts of the body because blood is closer to the surface in those areas. It bites the victim without pain because its saliva has an anesthetic chemical in it that numbs the bite site. A barbed feeding tube helps keep it latched on more securely. It draws a blood meal from the host until it is engorged with blood, and its abdomen more than doubles in size, turning redder in color. Ticks may feed on the same host for days. Not all tick bites leave a red ring around the wound, but the presence of one may indicate a bite.

All Ticks are arachnids, not insects. They have eight legs, so counting legs of a creature crawling on you can aid in identifying them quickly. Males appear dark brown or even black, while females feature red-orange coloring. Tick nymphs are most active during the spring and summer months, when a majority of potential hosts are also most active.

Picture of the Black-Legged Tick
Picture of the Black-Legged Tick

Black-Legged Tick Information

Category: Mite or Tick
Common Name: Black-Legged Tick
Scientific Name: Ixodes scapularis
Other Name(s): Deer Tick

Taxonomy Hierarchy

 Arrow graphic Kingdom: Animalia
  Arrow graphic Phylum: Arthropoda
   Arrow graphic Class: Arachnida
    Arrow graphic Order: Acari
     Arrow graphic Family: Ixodidae
      Arrow graphic Genus: Ixodes
       Arrow graphic Species: scapularis

Size, Identifying Tags and Territorial Reach

Size (Adult, Length): Size (Adult, Length): 3 mm to 4 mm (0.117 inches to 0.156 inches)
Identifying Colors: brown; red; black
Additional Descriptors: biting, harmful, 8 legs

North American Territorial Reach (Though Not Limited To): Minnesota; Iowa; Missouri; Oklahoma; Arkansas; Texas; Kansas; Wisconsin; Illinois; Indiana; Tennessee; Mississippi; Louisiana; Alabama; Kentucky; Indiana; Michigan; Ohio; West Virginia; North Carolina; South Carolina; Georgia; Florida; Virginia; Maryland; Delaware; Pennsylvania; New Jersey; New York; Connecticut; Massachusetts; Rhode Island; New Hampshire; Vermont; Maine

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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