Appearance
It has two subspecies, the nominate on the west Andean slope, and "leucura" on the east Andean slope. The two differ strongly, most conspicuously in that the former has a broad orange malar, which the latter lacks. Both have a straight black bill, greenish upperparts, a blue throat, grey belly, and extensive white to the tail. Although sharing the name hillstar with the members of the genus "Oreotrochilus", they are quite different and not closely related.References:
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