P. glabristoma has long been widely grown as Petrocosmea barbata, but is now properly known as P. glabristoma. It has some floral variation, especially in the degree of lavender shading in the flower. Flowers vary in size, and can be either pale lavender or white. In all cases there are two yellow splotches in the throat.
Additional photos can be seen in a slideshow by clicking one of the links below: