Krowtonan Guard

From Memory Alpha, the free Star Trek reference

The Krowtonan Guard were a military power in the Delta Quadrant, located near to the Ocampan Homeworld.

The USS Equinox encountered this civilization in the first week of their journey back to the Alpha Quadrant, when they unknowingly violated Krowtonan space. Rather than turn around and plot a course around the area - an action that would add six years to the 150-year journey - Equinox captain Rudolph Ransom chose to continue on. The resulting assault on the starship by the Guard cost the lives of 39 crewmembers. (VOY: "Equinox")

Despite being a major power so close to the Caretaker's array, Captain Kathryn Janeway stated that she never heard of the Guard before meeting Ransom.