I do not know if such list exists somewhere, but if the Heuchera is Terra Nova's introduction, you can see its species parents in the description.

For example, for Heuchera 'Black Beauty', the parents are villosa, micrantha.

Monet_g,
Just wondering - how come you call them "hercs"?
Wouldn't you call them "heucs"?
Vanessa

Thanks, Alina.
Vanessa, I guess I was in a hurry.

Hercs are what most of the old Herc people have been calling them for years. I do it all the time it is just a good short cut nickname for me. lol

Thanks for the link. I try to buy mostly Villosa

I just happen to have Dan Heim's book handy. These were all listed as Huechera villosa cultivars:

H. v. 'Autumn Bride', 'Biddulph Brown', 'Chantilly', 'Creme de la Creme', 'Discolor', 'Emperor's Cloak', 'Melkweg', f.purpurea 'Bronze Wave', f.p. 'Palace Purple', f.p. 'Royal Red'