Rabbit ticks? Widely found in the Americas

Notice a rabbit tick was found in Nantucket, but can also be found from Alaska to Argentina.

Haemaphysalis leporispalustris, the rabbit tick (occasionally known as the grouse tick), is a species of tick that is widely distributed in the Americas, stretching from Alaska to Argentina. H. leporispalustris is known to have one of the largest distributions for a tick originating in the New World. 

Strains of Rickettsia rickettsii, the disease aften of Rocky Mountain spotted fever have been found in the rabbit tick. Evidence of this bacteria in rabbit ticks have been found in countries such as Costa Rica and Argentina. A Brazilian strain of the Rickettsia rickettsii was also found recently in Rio de Janeiro in ticks found on wild rabbits as well as rabbit ticks in Costa Rica. 

Since rabbit ticks support the infection of virulent strains of this bacteria, H. leporispalustris contains a role in the maintenance of R. rickettsii in the Americas. H. leporispalustris is currently one of the known vectors that is keeping this bacteria in circulation. 

Also, H. leporispalustris transmits Coxiella burnetii and Francisella tularensis.^[10] Strains of Anaplasma bovis have also been found in rabbit ticks, which was discovered in a Nantucket tick study of the bacteria.

Source for info- WIKI

https://en.wikipedia.org/wiki/Haemaphysalis_leporispalustris