White-throated Tyrannulet (Mecocerculus leucophrys) [XC841815]
by id from Loja: Acacana, Ecuador (dawn song)
White-throated Tyrannulet (Mecocerculus leucophrys) [XC785697]
by Niels Krabbe from Finca Suasie Birdwatching & Lodging, La Calera, Cundinamarca, Colombia (call)
Subspecies
Genus as presently constituted is probably polyphyletic, and in need of further study. Not obviously related to any of forms currently treated as congeners. Subspecies pallidior has been suggested as warranting species rank. Species exhibits dramatic "leapfrog" pattern of geographical variation: birds of small size and bearing extremely similar colour patterns occur at northern and southern ends of range, with much larger and more richly coloured forms in intervening cordilleras. In view of the remarkable differences existing between certain populations that occupy adjacent mountain ridges, several described taxa referring to marginally discernible intermediates are probably better merged with neighbouring forms: montensis (Santa Marta Mts, in Colombia) and palliditergum (Venezuelan coastal mountains from Yaracuy east to Miranda) merged with nigriceps, and gularis (Sierra de Perijá and Mérida Andes, in western Venezuela) with setophagoides.
The following 11 subspecies are recognised:
notatus Todd, 1919 - Western and central Andes of Colombia (south to Cauca).
setophagoides (Bonaparte, 1845) - Eastern Andes of north-western Venezuela (western Zulia and Táchira east to southern Lara) and Colombia (Norte de Santander south to Cundinamarca).
nigriceps Chapman, 1899 - Mountains of northern Colombia (in Santa Marta region) and northern Venezuela (Yaracuy east to Sucre and Monagas).
roraimae Hellmayr, 1921 - Tepui zone of Amazonas (except Cerro Parú and Cerro Duida) and Bolívar, in southern and south-eastern Venezuela. Also adjacent parts of northern Brazil and western Guyana.
chapmani Dickerman, 1985 - Cerro Duida, in central Amazonas (Venezuela).
rufomarginatus (Lawrence, 1869) - Andes of southern Colombia (Nariño), Ecuador and north-western Peru (Piura).
pallidior Carriker, 1933 - Western Andes of Peru (Ancash).
brunneomarginatus Chapman, 1924 - Eastern Andes of Peru (south to Cuzco).
leucophrys (D'Orbigny & Lafresnaye, 1837) - Eastern Andes from southern Peru (southern from Cuzco and Madre de Dios) south to northern Argentina (Salta, Tucumán).
montensis (Bangs, 1899) - Santa Marta Mts. (north-eastern Colombia).
BirdLife International Species Factsheet