Scaled Metaltail

The scaled metaltail is 12 to 13 cm (4.7 to 5.1 in) long and weighs 5.2 to 5.4 g (0.18 to 0.19 oz). It has a medium length, straight, black bill. The adult male of the nominate subspecies has bottle green upperparts. Its slightly forked tail is iridescent sky blue with bronzy green tones on its upper side and glittering green on its underside. Its gorget is iridescent bright green. The rest of its underparts are green with a scaly appearance from tan feather margins. The adult female is similar to the male. Its gorget is smaller and its undersides are more mottled. Juveniles are similar to the female. Subspecies M. a. malagae is similar to the nominate but the upper side of its tail is bronzy red and the underside red. It also has a longer bill.

The nominate subspecies of scaled metaltail is found on the eastern slope of the Andes from the Cordillera Vilcabamba of southeastern Peru south into northwestern Bolivia's La Paz Department. M. a. malagae is found in the vicinity of Inkachaka in central Bolivia's Cochabamba Department. The species inhabits glades and edges of cloudforest and elfin forest and also rocky slopes with herbs and shrubs. In elevation it ranges between 2,500 and 3,600 m (8,200 and 11,800 ft) and is most common above 3,000 m (9,800 ft).

The scaled metaltail feeds on nectar from a variety of flowering plants and shrubs, often by clinging to the flower. Males defend feeding territories. In addition to nectar, it feeds extensively on insects.