Smallest one I've ever seen. I thought it was a speck of dirt. It makes me wonder about all the times I didn't see ones this small...
Tick is the common name for the small arachnids in superfamily Ixodoidea that, along with other mites, constitute the Acarina. Ticks are ectoparasites (external parasites), living by hematophagy on the blood of mammals, birds, and occasionally reptiles and amphibians. Ticks are vectors of a number of diseases, including Lyme disease, Q fever, Colorado tick fever, tularemia, tick-borne relapsing fever, babesiosis, ehrlichiosis and Tick-borne meningoencephalitis, as well as anaplasmosis in cattle and canine jaundice.