Averla-formicaia dell'altopiano

Identificazione

The upland antshrike is 14.5 to 15 cm (5.7 to 5.9 in) long and weighs about 20 g (0.71 oz). Members of genus Thamnophilus are largish members of the antbird family; all have stout bills with a hook like those of true shrikes. This species exhibits significant sexual dimorphism. Adult males have medium gray upperparts with a blacker crown and a hidden white patch between their scapulars. Their wings are black or brownish black and their wing coverts have white tips. Their tail is black or brownish black with white tips on all but the central pair of feathers. Their underparts are a slightly paler gray than their upperparts. Adult females have a dark rufous crown and nape and a gray face with white streaks or spots. Their upperparts are dark olive-brown. Their underparts are tawny olive or tawny brown. Both sexes have a highly variable (from buffy white to brown) iris color, a black maxilla, a paler mandible, and gray or blue-gray legs and feet. Juvenile males are similar to adult females but have buff spots on their wing coverts and buff tips on their tail feathers.

Tassonomia

The upland antshrike is monotypic.

Nome scientifico

Thamnophilus aroyae

Autorità

(Hellmayr, 1904)

Ordine

Passeriformi

Famiglia

Thamnophilidae

Genere

Thamnophilus

Areale e habitat

The upland antshrike is found in the Andean foothills from the Department of Puno in extreme southeastern Peru southeast to Cochabamba and western Santa Cruz departments in Bolivia. It inhabits the edges of humid montane forest, where it favors dense shrubby areas and vine tangles, and almost never penetrates far into the forest interior. It also occurs in newer regrowth in landslide scars and along roads. One publication states its elevational range as between 800 and 1,000 m (2,600 and 3,300 ft) in Peru and up to 1,700 m (5,600 ft) in Bolivia. Another states a wider range in Bolivia of 600 to 1,900 m (2,000 to 6,200 ft).

Migrazione

Resident species

Comportamento

The upland antshrike is presumed to be a year-round resident throughout its range.<p>The upland antshrike's diet is not known in detail but is mostly insects. It usually forages singly or in pairs and infrequently joins mixed-species feeding flocks. It usually forages between 1.5 and 3 m (5 and 10 ft) above the ground but will feed as high as 6 m (20 ft). It gleans prey from leaves, stems, vines, and branches while perched and with short upward sallies. It also searches in clusters of dead leaves caught in vine tangles.<p>Nothing is known about the upland antshrike's breeding biology.<p>The upland antshrike's song is "a fast-paced, accelerating series of nasal notes, ending in a downslurred terminal note...wur wur-wur-wur-wur'rrrr". Its calls include "high whines; a drawn-out, modulated, throaty, descending caw aarrrr; and a mewing awww".

Conservazione

Tendenza della popolazione

declining