This is a small, rather plain crayfish without bright colors or bold markings. Its most distinctive feature is a pale, vase-shaped zone along the middle of the dark olive-tan carapace. The pincers are broad and powerful. Similar species within the range of Williams' crayfish are the Ozark crayfish (Orconectes ozarkae), which has numerous dark specks on the pincers and abdomen, and the ringed crayfish (O. neglectus), which has prominent black or brown rings near the tips of the fingers. These species reach a larger size than Williams' crayfish.