Ashy Antwren

Identification

The Jungas antwren is 8.5 to 9.5 cm (3.3 to 3.7 in) long and weighs 8 to 10 g (0.28 to 0.35 oz). It is a smallish bird with a short tail. Adult males are almost entirely gray with slightly darker and more brownish gray wings and tail than body. Adult females have a brownish yellow face. Their upperparts are mostly olive-brown, with a grayish tinge from the crown to upper mantle and yellowish brown tips on the uppertail coverts. Their tail is dark brown with rufous-brown edges to the feathers. Their chin and throat are brownish yellow and their underparts yellow-ochre that is browner on their flanks and crissum. Subadult males are like adults with patches of yellowish brown.

Taxonomy

The Yungas antwren is monotypic. It, the unicolored antwren (M. unicolor), the Alagoas antwren (M. snowi), and the plain-winged antwren (M. behni) appear to form a monophyletic group with similar vocalizations and habitat requirements.

Scientific name

Myrmotherula grisea

Authority

Carriker, 1935

Order

Passeriformes

Family

Thamnophilidae

Genus

Myrmotherula

Range and habitat

The Jungas antwren was long thought to be endemic to western Bolivia, where it is found on the eastern base of the Andes in the departments of La Paz, Cochabamba, and Santa Cruz. Some taxonomic systems still list it only in that country. However, since the early 21st century it has been documented in southeastern Peru's departments of Cuzco and Puno.<p>In both countries the Jungas antwren inhabits the mid-storey and subcanopy of evergreen forest in foothills and the submontane zone. It also occurs in the forest's understory at its edges. In elevation it occurs from 500 to 1,650 m (1,600 to 5,400 ft) but is mostly found between about 700 and 1,200 m (2,300 and 3,900 ft).

Migration

Resident species

Behavior

The Jungas antwren is believed to be a year-round resident throughout its range.<p>The Jungas antwren's diet is not known in detail but is probably mostly mostly insects and spiders. It forages singly, in pairs, or in family groups, and often as part of a mixed-species feeding flock. It feeds mostly between about 1 and 20 m (3 and 70 ft) above the ground. It energetically seeks prey mostly from clusters of dead leaves, and also takes prey from live leaves and moss.<p>Nothing is known about the Jungas antwren's breeding biology.<p>The Jungas antwren's song is "a series of simple, slightly downslurred notes on approximately same pitch (c. 4 kHz), delivered rapidly, notes much longer than intervals". Its calls "include sharp, upslurred 'wheep' and upslurred doubled-noted 'do-leep' ".

Conservation

Population trend

declining