Photo and text by Bob Stewart
The foliage of A. cristatus is a lot like Columnea repens (aka jamaicensis). It is a thin-stemmed vine, and can become quite long. It has small leaves, and is easy growing but not easy blooming. I had never seen the flower until ours finally bloomed. I don't know whether it is just luck or whether we finally let it grow large enough, or what.
This photo is of the fruit of this species. The yellowish "covers" of the fruit are folded back, and the seeds are seen as the black mass in the centre of the "covers".
A similar fruit display on a Corytoplectus species can be seen here.