The Kovaalan starship was a type of starship used by the Kovaalans during the 22nd century.
In February of 2154, when Enterprise NX-01 attempted to travel through a subspace corridor leading to the Xindi Council planet, six Kovaalan ships were patrolling the nebula and attacked. Enterprise made it through with the help of a future version of itself. (ENT: "E²")
In the final draft script of "E²", each Kovaalan ship was described as being "about half the size" of an NX-class starship.