White-sided Hillstar (Oreotrochilus leucopleurus) [XC38816]
by Doug Knapp from Le\u00f3n, Jujuy, Argentina (agonic calls?)
White-sided Hillstar (Oreotrochilus) [XC719953]
by Ignacio Escobar from San Jos\u00e9 de Maipo, Cordillera, Regi\u00f3n Metropolitana, Chile (?)
Subspecies
Forms a superspecies with Andean Hillstar (Oreotrochilus estella), Ecuadorian Hillstar (Oreotrochilus chimborazo) and Green-headed Hillstar (Oreotrochilus stolzmanni), and all have been considered conspecific, but separated largely on morphological grounds. Andean Hillstar (Oreotrochilus estella) overlaps slightly with present species, and some hybridization reported, in spite of which present species is the form least frequently lumped into Andean Hillstar (Oreotrochilus estella).