Amblyomma triste is a tick in the Amblyomma genus. The tick can be found in Venezuela, Argentina, Brasil, Colombia, Peru and Uruguay.[1][2] Though not thought to be endemic to North America, a 2010 study found 27 specimens in 18 separate collections that had previously been misidentified in the United States.[3]
The species has been found to carry the human-infectious Rickettsia parkeri which produces symptoms similar to Rocky Mountain spotted fever.[4] The tick is the only tick responsible for tick-borne disease in humans in Uruguay,[4] and has been identified as a significant vector of disease in Argentina and Brazil.[3]
The tick was first described by Koch in 1844.[1] The tick is morphologically similar to Amblyomma maculatum and Amblyomma tigrinum. both of which are also carriers of Rickettsia parkeri.[5] Identification of the species in North America, is often due to the fact that they are cryptic species with those two species.[3]