Amblyomma americanum

Amblyomma americanum, also known as the lone star tick, northeastern water tick, turkey tick, and cricker tick, is a type of tick indigenous to much of the eastern United States and Mexico that bites painlessly and commonly goes unnoticed, remaining attached to its host for as long as seven days until it is fully engorged with blood. It bites aggressively, and its larvae may transfer themselves to skin from discarded clothing that is put back on. The sexually dimorphic adult female lone star tick bears a silvery-white, somewhat star-shaped spot near the center of the posterior portion of its dorsal shield (scutum); adult males conversely have varied white streaks or spots around the margins of their shields.

It is to this spot, not to Texas, that A. americanum owes the name lone star tick, while it owes the name turkey tick to the wild turkeys that are a common host in its immature stages in some Midwestern U.S. states. It is the primary vector of Ehrlichia chaffeensis, which causes human monocytic ehrlichiosis, and Ehrlichia ewingii, which causes human and canine granulocytic ehrlichiosis. Its bite may also cause a human to develop alpha-gal syndrome, an allergy to non-catarrhine mammalian meat. Other disease-causing bacterial agents isolated from lone star ticks include Francisella tularensis, Rickettsia amblyommii, and Coxiella burnetti.