These medium-sized hummingbirds are shining green and males have stunning violet gorgets. The extent of gorget coloration is highly variable on females, possibly even changing seasonally, and with gorgets sometimes appearing whitish and not at all purple. Both sexes have deeply forked tails. Purple-throated Sunangels live in cloud forests, forest edges, thickets, alder (Alnus) woodlands, second growth, and shrubby areas. Males are often seen out on open perches. In some parts of Ecuador, these hummingbirds appear to rely on flowers of Eucalyptus trees.