Buccella molossus

Purchased as Buccella or Masdevallia molosoides, this has been identified as a similar-looking species, Bucella molossus.  The former is from Costa Rica and Panama.  This is from Colombia.  It is a tiny plant, 4-5 cm tall with 1 cm flowers born singly.  It prefers cooler temperatures and blooms in the spring.  I grow it in a net pot in sphagnum moss.