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Carios kelleyi

Carios kelleyi

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Carios kelleyi


Carios kelleyi is distributed widely in the United States, with records from AL, AR, AZ, CA, CO, CT, GA, IL, IA, KY, Maryland, MI, MN, MO, MT, (recently NJ), NM, NV, NY, PA, SD, TX, UT, WA, and WI. In Canada, it occurs in AB and SK and in MX, Sonora and Durango.

Unlike many species of argasid ticks, C. kelleyi larvae are slow feeders requiring days (9-20) to engorge, which may explain the widespread distribution of this species as it may be easily transported by its host.


This tick usually feeds on bats and is reported from at least five genera of bats in North America, especially Myotis spp. They have been reported to bite humans. Human encounters may occur when bats vacate roosts or hibernacula, especially if roosting in homes.

Vector Status

A Borrelia bacterium has been isolated in this tick as a relapsing fever spirochete most closely related to, but distinct from Borrelia turicatae; Candidatus Borrelia johnsonii. DNA from Rickettsia sp., Borrelia sp., and Bartonella henselae, the causative agent of cat scratch disease, were isolated in C. kelleyi ticks from Jackson Co., IA, the same population population of bats reported to bite humans.


H Joel Hutcheson, James W Mertins, Boris C Kondratieff, Monica M White, Ticks and Tick-Borne Diseases of Colorado, Including New State Records for Argas radiatus (Ixodida: Argasidae) and Ixodes brunneus (Ixodida: Ixodidae)Journal of Medical Entomology, tjaa232,

Carios kelleyi (Bat Tick), Image by James Gathany-CDC