Fork-tailed Woodnymph (Thalurania furcata) Science Article 1
We analyzed geographic variation in morphology and plumage coloration in male woodnymphs of the genus Thalurunia in Middle America and northwestern South America. Morphometric characters distinguish the disjunct western Mexican populations from populations to the south. Three groups are distinguished by discrete plumage coloration characters. We propose that these groups be recognized as separate species: T. ridgwuyi of western Mexico; T. colombica of Central America south to western Panama and disjunctly in interior Northwestern South America; and T.fannyi ofeastem Panama, western Colombia, and northern Ecuador.
PATRICIA ESCALANTE-PLIEGO AND A. TOWNSEND PETERSON, Wilson Bull., 104(2), 1992, pp. 205-219