Columnea cruenta

Photo by Larry Skog, courtesy of the Smithsonian Institution
Grown at Cheekwood Botanical Garden

Also known as Dalbergaria cruenta.  A closeup of a flower cluster can be seen by clicking here and another specimen here.

Like many other species in the Dalbergaria group, C. cruenta has red markings on the underside of the leaves, which apparently play a role in attracting insect pollinators.