Lyndon Lyon Greenhouses carries both A. tricolor and C. schiedeana. Columnea schiedeana is the same as C. flava, with C. schiedeana being the accepted name.

Here is a link that might be useful: Lyndon Lyon Greenhouses

Ahh I see LLG has A. tricolor but I think you thinking of C.'Lava Flow' which has C. schiedeana in its parentage. C. flava has a bright yellow flower on small red-edged leaves, similar to C.'Apollo' flower.

Columnea flava/schiedeana are synonyms, with the yellow and maroon variant being the most common. A completely yellow form was distributed by the Gesneriad Research Center at Selby Gardens, Sarasota, Fl. I can't find it for sale anywhere, and I'm not sure how widely distributed it was, or if the GRC would be willing to part with cuttings. Selby Gardens can be reached at:

941-366-5731

Here is a link that might be useful: Yellow C. flava

Shelby Gardens won't turn anything loose. I've tried several times to get stuff from them. When Hans Wiehler died, so did the source for plant material. Thanks for the link. I have 2 variants of C schiedeana, but didn't know of a yellow variation. BTW, if you want to do some plant trading, send me an email.