Masdevallia triangularis is accepted species in  the family Orchidaceae  subfamily: Epidendroideae, tribe: Epidendreae, subtribe: Pleurothallidinae,  
Genus Masdevallia   subgenus Masdevallia  section: Masdevallia   subsection: Caudatae 
Infraspecific taxa recognized within Masdevallia triangularis: infraspecific taxa
This species is found in NW. & N. Venezuela to Ecuador.