Systematics

Three subspecies are recognized (Fjeldså and Krabbe 1990)

stolzmanni Salvin 1895; type locality Huamachuco, 10400 feet and near Cajamarca, 10000 and 12000 feet, Perú

Occurs from extreme southern Ecuador south through the Andes to central Peru in Huánuco, Lima, and Pasco.

Similar to nominate estella, but the median breast band of the male is black, and the upperparts in both sexes are bronzier (Fjeldså and Krabbe 1990).

estella (d'Orbigny and Lafresnaye 1838); type locality La Paz and Potosí, Bolivia

Occurs from south central Peru (Ayacucho, Apurímac and Cuzco) south through northwestern Bolivia to northern Chile (Tarapacá).

See Detailed Description.

bolivianus Boucard 1893; type locality Bolivia, restricted to Lagonillas, 3500 m, Cochabamba, Bolivia

Median breast stripe of male broad and chestnut, somewhat spotted with black; gorget often blue green, not bright green.

Occurs in southern Bolivia and in northwestern Argentina.

Oreotrochilus estella sometimes is considered to be a member of a superspecies including O. chimborazo (Ecuadorian Hillstar), O. leucopleurus (White-sided Hillstar), and perhaps also O. melanogaster (Black-breasted Hillstar) (Schuchmann 1999). The number of species recognized within this complex varies widely. Zimmer (1951) included chimborazo and leucopleurus in estella, but maintained melanogaster as a separate species. Most recent authors recognize chimborazo and leucopleurus as distinct species, but treatments differ over the inclusion of stolzmanni in estella. The distribution of melanogaster, in central Peru, separates stolzmanni, which occurs from southern Ecuador to central Peru, from the southern taxa of estella (nominate estella, bolivianus); some authors recognize stolzmanni as a separate species (e.g. Schuchmann 1999).

Phylogenetic analysis of DNA sequence data, from both mitochondrial and nuclear genes, indicates that Oreotrochilus is embedded within a radiation of Andean hummingbirds (McGuire et al. 2007, 2009). Within this radiation, Oreotrochilus is basal to a clade that includes Opisthoprora, Lesbia, Ramphomicron, Chalcostigma, Oxypogon, Oreonympha, and Metallura (McGuire et al. 2007, 2009).