White-crested Tyrannulet (Serpophaga subcristata) [XC483725]
by Rosendo Manuel Fraga from Campus UFPel, Cap\u00e3o do Le\u00e3o, Rio Grande do Sul, Brazil (call)
White-crested Tyrannulet (Serpophaga subcristata) [XC344505]
by Jeremy Minns from Barra do Quara\u00ed, Brazil (song)
Subspecies
Taxonomic status controversial. Sometimes considered conspecific with White-bellied Tyrannulet (Serpophaga munda), but the two differ in plumage, also slightly in voice, and in Argentina are narrowly parapatric with limited hybridization. Further study is required.
The following 2 subspecies are recognised:
subcristata (Vieillot, 1817) - Bolivia (from northern La Paz) and southern Brazil (southern from southern Mato Grosso) south through Paraguay to Argentina (south to northern Chubut).
straminea (Temminck, 1822) - South-eastern Brazil (southern Piauí and Bahia south to Rio Grande do Sul) and Uruguay.