By progenitor race I’m thinking like the Xel’Naga in StarCraft or the Forerunners in the Halo series. Even the Xeelee in Stephen Baxters Xeelee Sequence could fit that classification albeit loosely, seeing as how their race is a complex in many senses and resists easy classification in neat little categories.
To digress in a fascinating direction, Baxter’s Xeelee are not even purely baryonic lifeforms but rather “evolved from” sentient self-assembled topological defects in spacetime that merrily (as in jolly, not a misspeled merely) swathe themselves in baryonic matter the better to interact with other baryonic stuff.
I put quotes around “evolved from” because it’s made clear that the beings I just described were the long, long-ago ancestors of “today’s” Xeelee (the ones in the books), having repeatedly evolved through a 20 billion year sequence of repeatedly using closed timeline curves to give themselves many more hundreds of billions of years to combat the photons birds.