Download the PDF(opens in new tab)
Know Your Ticks
A practical introduction to major disease-vector ticks.
- Pictures
- Behaviors
- Geography
- Diseases they can transmit
Tickborne disease requires the right chain
Correct tick
Only certain tick species can transmit a given pathogen.
Infected host
A feeding tick acquires a pathogen from an infected host.
Attached feeding
The tick attaches and feeds; transmission time varies by pathogen.
Human exposure
An infected tick may transmit a pathogen during feeding.
Three tick groups explain many U.S. disease risks
Ixodes
Ixodes speciesAmblyomma
Amblyomma speciesDermacentor
Dermacentor speciesAdditional important groupBrown dog ticks belong to Rhipicephalus—not one of the three groups shown above.
Six ticks worth knowing
Filter by group, then tap a tick to open its ID card with adult, nymph and larva views.
![]()
Deer tick or Blacklegged tick
the major eastern Lyme vector
Ixodes
Deer tick or Blacklegged tick
the major eastern Lyme vectorMajor group → Ixodes
8 legsLarva
6 legs
Typical unfed size: adult 2–5 mm • nymph 1–2 mm • larva <1 mm
Juvenile appearance varies by species. Confirm specimens with a regional identification key.
Male: smaller and dark across most of the back. Female: black legs and front shield contrast with a reddish-orange abdomen.
Waits on low vegetation for passing hosts; nymphs and adult females commonly bite people.
Widely distributed across the eastern United States
Northeast, mid-Atlantic and upper Midwest forested areas
![]()
Western blacklegged tick
the Pacific Lyme vector
Ixodes
Western blacklegged tick
the Pacific Lyme vectorMajor group → Ixodes
8 legsLarva
6 legs
Typical unfed size: adult 2–5 mm • nymph 1–2 mm • larva <1 mm
Juvenile appearance varies by species. Confirm specimens with a regional identification key.
Male: smaller with a mostly dark back. Female: dark legs and front shield with a reddish-brown posterior abdomen.
Larvae and nymphs commonly feed on lizards, birds and rodents; adults often feed on deer.
Found along the Pacific coast of the United States
Particularly important in northern California and parts of Oregon and Washington
![]()
Lone star tick
aggressive and easy to recognize
Amblyomma
Lone star tick
aggressive and easy to recognizeMajor group → Amblyomma
8 legsLarva
6 legs
Typical unfed size: adult 2–5 mm • nymph 1–2 mm • larva <1 mm
Juvenile appearance varies by species. Confirm specimens with a regional identification key.
Male: multiple pale markings around the body and shield. Female: one unmistakable solitary white dot on her back.
An aggressive tick that actively seeks hosts; larvae, nymphs and adults can bite people.
Widely distributed across the Northeast, South and Midwest
Established populations have moved farther north with deer and habitat changes
![]()
American dog tick
a widespread spotted-fever vector
Dermacentor
American dog tick
a widespread spotted-fever vectorMajor group → Dermacentor
Typical unfed size: adult 2–5 mm • nymph 1–2 mm • larva <1 mm
Juvenile appearance varies by species. Confirm specimens with a regional identification key.
Male: ornate shield covers nearly the entire back. Female: ornate shield covers only the front, leaving a plain brown abdomen.
Common in grassy areas, trails and field edges. Highest human-bite risk is in spring and summer.
Widely distributed east of the Rocky Mountains
Also occurs in limited western areas; a related species, D. similis, occurs farther west
![]()
Rocky Mountain wood tick
a western disease vector
Dermacentor
Rocky Mountain wood tick
a western disease vectorMajor group → Dermacentor
8 legsLarva
6 legs
Typical unfed size: adult 2–5 mm • nymph 1–2 mm • larva <1 mm
Juvenile appearance varies by species. Confirm specimens with a regional identification key.
Male: ornate shield covers nearly the entire back. Female: ornate shield is limited to the front of the reddish-brown abdomen.
Adults commonly quest on vegetation in brushy foothill and mountain habitats.
Rocky Mountain states and western Canada
Human exposure is often greatest during spring and early summer
![]()
Brown dog tick
adapted to homes and kennels
Rhipicephalus
Brown dog tick
adapted to homes and kennelsAdditional group → Rhipicephalus
8 legsLarva
6 legs
Typical unfed size: adult 2–5 mm • nymph 1–2 mm • larva <1 mm
Juvenile appearance varies by species. Confirm specimens with a regional identification key.
Both sexes are uniformly reddish-brown. Male: shield covers nearly the full back. Female: front shield leaves a plain abdomen.
Dogs are the primary host through all life stages. It can complete its life cycle indoors.
Found nearly worldwide and throughout the United States
RMSF transmission is especially important in parts of the Southwest and U.S.–Mexico border region
Quick reference: tick, geography and disease
Search by tick, region or disease. Tap a name to open its ID card.
| Tick | Typical geography | Most recognized disease links |
|---|---|---|
| Blacklegged | Eastern U.S.; Northeast + upper Midwest | Lyme, anaplasmosis, babesiosis, Powassan |
| Western blacklegged | Pacific Coast, especially northern California | Lyme, anaplasmosis, hard tick relapsing fever |
| Lone star | Northeast, South and Midwest | Ehrlichiosis; STARI and alpha-gal association |
| American dog | Mostly east of the Rocky Mountains | Rocky Mountain spotted fever (RMSF), tularemia |
| Rocky Mountain wood | Rocky Mountain states and western Canada | RMSF, Colorado tick fever, tularemia |
| Brown dog | Worldwide; homes and kennels | RMSF in parts of the Southwest and Mexico |
Remember: tick presence alone does not show whether local ticks are infected.
Avoid the habitat.
Check for ticks.
Remove them promptly.
Use an EPA-registered repellent like Summit® Green Armor to treat your shoes, clothes, outdoor gear and dogs as directed to repel and kill ticks.
Shower soon after returning indoors; dry clothes on high heat.
Inspect your body, clothing, gear and pets after being outdoors.
Use Summit® Tick-Take™ to safely remove attached or crawling ticks without touching them.
If fever, rash or other illness follows a tick bite, contact a healthcare professional.
Sources & illustration notes
Illustrations are educational reconstructions generated for this learning aid. Use identification keys or local vector-control experts for specimen-level identification. Juvenile size ranges are approximate and vary by species and feeding status. Geographic presence does not by itself mean local disease transmission.
- cdc.gov/ticks/about/index.html
- cdc.gov/ticks/after-a-tick-bite/index.html
- cdc.gov/ticks/about/where-ticks-live.html
- cdc.gov/ticks/data-research/facts-stats/blacklegged-tick-surveillance.html
- cdc.gov/lyme/causes/index.html
- stacks.cdc.gov/view/cdc/52631
- cdc.gov/ticks/data-research/facts-stats/western-blacklegged-tick-surveillance.html
- cdc.gov/anaplasmosis/hcp/transmission/index.html
- cdc.gov/ticks/data-research/facts-stats/lone-star-tick-surveillance.html
- cdc.gov/stari/about/index.html
- cdc.gov/ehrlichiosis/hcp/clinical-overview/index.html
- cdc.gov/ticks/data-research/facts-stats/american-dog-tick-surveillance.html
- tickapp.tamu.edu/home/tick-identification/american-dog-tick
- pa.gov/agencies/dep/programs-and-services/bureau-of-labs/vector-management/ticks/american-dog-tick
- cdc.gov/rocky-mountain-spotted-fever/about/index.html
- cdc.gov/colorado-tick-fever/data-maps/index.html
- cdc.gov/mmwr/preview/mmwrhtml/00040975.htm
- cdc.gov/dpdx/ticks/index.html
- cdc.gov/rocky-mountain-spotted-fever/hcp/clinical-overview/index.html
- stacks.cdc.gov/view/cdc/27722
- cdc.gov/ticks/prevention/index.html
- epa.gov/insect-repellents/find-repellent-right-you
