Lesser Violetear is locally common in montane regions of southern Central America and of South America, from Costa Rica south to northern Argentina, and east to the coastal mountains of northern Venezuela. Formerly Lesser was included with Mexican Violetear (Colibri thalassinus), which occurs from Mexico to Nicaragua, as a single species ("Green Violetear", C. thalassinus), but Mexican and Lesser violetears differ significantly from one another in plumage, and now are classified as separate species. All species of violetears (Colibri), including Lesser, have a patch of elongated violet feathers on the sides of the head (hence the English name). Lesser Violetear otherwise is mostly glittering green; most populations have a purely green breast, lacking the bright blue breast patch of Mexican Violetear, but reportedly some specimens of Lesser, from the northern part of the range, in Costa Rica, also may have some blue on the underparts. Lesser Violetear inhabits highland humid forest borders, clearings and highland pastures, and is resident throughout its range.