Kelis' species

From Memory Alpha, the free Star Trek reference.

Kelis' species are a primitive humanoid species native to Kelis' homeworld, a Class L planet located in the Delta Quadrant. Individuals of Kelis' species worship gods whom they refer to as the Eternals. (VOY: "Muse")

By 2376 members of this species had been assimilated by the Borg. (VOY: "Unimatrix Zero", "Unimatrix Zero, Part II")

The Borg child of this species refers to having been assimilated in his father's ship, indicating that some members of this species had achieved space flight by that time.