Pacific Coast tick

Family: Ixodidae. Genus: Dermacentor. Hard tick.

Adults are ornate Dermacentor ticks with short mouthparts, eyes and festoons. Similar Dermacentor species require expert morphological separation.

Photographs and location alone may be insufficient for confirmation; use expert morphological examination when reliable species identification is required.

Photographs alone cannot always confirm this species. Geographic location and host are supporting context, not conclusive identification.

Females have a smaller anterior scutum and expandable posterior body; males have a scutum covering most of the dorsum.

Three-host hard-tick life cycle with egg, larva, nymph and adult stages.

Human cases cited by CDC have occurred in summer, but tick activity and encounter timing vary regionally.

CDC describes occurrence in coastal ranges of Oregon and California and in Baja California and Sinaloa, Mexico.

Bites humans and transmits Pacific Coast tick fever; reported human cases remain uncommon.

Adults feed on horses, cattle and black-tailed deer; immature ticks feed mainly on rodents and rabbits.

Confirmed vector of the agent of Pacific Coast tick fever. Historical associations with other agents require source-specific interpretation.

Use current public-health and veterinary guidance, avoid known tick habitats where practical, use suitable repellents or protective clothing, and check people and animals after exposure.

Remove attached ticks promptly using fine-tipped tweezers or an appropriate tick-removal tool. Seek medical or veterinary advice when symptoms or concerns arise.