Orconectes obscurus is a species of crayfish in the family Cambaridae. It is native to the northeastern United States, where it occurs in Maryland, New York, Ohio, Pennsylvania, Virginia, and West Virginia. It is an introduced species in adjacent regions, including Massachusetts, Vermont, and Ontario in Canada. It is known commonly as the Allegheny crayfish and the obscure crayfish. This species lives in slow-moving waterways and pools with rocky substrates, where it hides beneath rocks. It also burrows into the substrate.