Metallura williami (Delattre & Bourcier, 1846)

Common Name and Basic Measurements

Metallura williami, commonly called the viridian metaltail, is 11 to 12 cm (4.3 to 4.7 in) long and weighs 4.1 to 5.3 g (0.14 to 0.19 oz). It has a medium-length, straight, black bill.

Nominate Adult Male Plumage

Adult males of the nominate subspecies have bottle green upperparts and underparts, a glittering bottle green gorget, and a slightly forked purplish blue tail.

Nominate Adult Female Plumage

Adult females also have bottle green upperparts; their throat, breast, and belly are mottled green and white, and the undersides of their outer tail feathers have whitish tips.

Juvenile Plumage

Juveniles have a similar appearance to adult females.

Subspecies Physical Variation Overview

Four subspecies have distinct physical differences when compared to the nominate subspecies.

M. w. recisa Physical Traits

M. w. recisa has a shorter bill, a more deeply forked tail, and shinier underparts.

M. w. primolina Physical Traits

M. w. primolina has a tail that is reddish black on top, shining green below, and only slightly forked.

M. w. atrigularis Physical Traits

M. w. atrigularis has a black patch at the center of its gorget, a slightly forked tail, and a shining green tail underside.

Subspecies Distribution Overview

Each of the four subspecies occupies a separate geographic range along the Andes in Colombia, Ecuador, and near the border of Peru.

M. w. recisa Range

M. w. recisa is found in the municipality of Frontino, in the Western Andes of Colombia’s Antioquia Department.

Nominate Subspecies Range

M. w. williami (the nominate subspecies) is found on both slopes of Colombia’s Central Andes.

M. w. primolina Range

M. w. primolina ranges from the Andes of southern Colombia’s Nariño Department into Ecuador, extending south as far as Ecuador’s northern Azuay Province.

M. w. atrigularis Range

M. w. atrigularis is found in the Andes of southern Ecuador, ranging from Morona-Santiago Province almost to the border of Peru.

Habitat

The viridian metaltail inhabits páramo grasslands with scattered shrubs, as well as the shrubby edges of humid montane forest and elfin forest.

Ecuador Elevation Range

In Ecuador, it usually occurs at elevations between 2,700 and 3,600 m (8,900 and 11,800 ft).

Colombia Elevation Range

In Colombia, it can range up to 4,000 m (13,000 ft).

Minimum Elevation Record

There have been confirmed sightings of the species at elevations as low as 2,100 m (6,900 ft).