A. pachyanthus is a newly described cultivar, with unusual pinkish flowers and very broad corolla lobes. The calyx also holds the corolla in an unusually firm grasp. Closeups of the flowers, and a view of the long leafless stems that clamber up supporting trees with an effect similar to the roots of some epiphytic orchids.
Mary Mendum of the RBGE has been studying this species, as part of her preparation for a broad re-working of the genus. She reports that A. pachyanthus was collected in Papual, New Guinea, at an altitude of about 1900 meters.