I bought a couple of rhizomes of diastema vexans on ebay in the early spring of 2009.  They started
blooming in late July or early august.  I tried a couple of crosses with them, but I had a lot of kittens
this year and they tore the tops off one whole bench, including these.  I did manage one cross to
Seemannia purpescens which is up and growing.
I also have diastema luteola that I bought at the 2007 TGS show, but they have never bloomed.  
They grow and produce rhizomes, but no blooms.
Just recently ordered the seed for diastema affine JLC9964 from the 'Gesneriad Society' and have
the first seedlings sprouting now.  
At left is Diastema vexans, not a great picture, but it was
growing outside.
@copyright Brad Walker Dec. 6, 2009