Aedes epactius is a species of mosquito in the family Culicidae, native to North America. This species is recognized for its adaptability to a variety of breeding sites, including natural rock pools and artificial containers like tires and flower pots. It is an avid biter and has been studied for its potential role in transmitting diseases such as the St. Louis encephalitis virus, though its impact as a vector remains limited compared to other mosquito species.