Moustached Antwren

The Moustached Antwren, a diminutive bird of the Neotropical realm, is a member of the Thamnophilidae family, known colloquially as the "typical antbirds." This species, Myrmotherula ignota, is characterized by its notably small stature, measuring a mere 7.5 to 8 cm in length, and its rather short tail.

Identification Tips

Adult males of the nominate subspecies are distinguished by a prominent black "moustache," a black streak through the eye, and white cheeks. Their plumage is predominantly black with delicate white streaks, which may exhibit a faint yellow hue, save for the crown. A distinctive white patch is present between the shoulders. The wings are black with white-tipped coverts and white-edged flight feathers, while the underparts are a vibrant yellow with sparse black streaks. Females, on the other hand, display buff to tawny buff streaks on the crown and lack the white shoulder patch. The subspecies M. i. obscura males have fewer pale streaks on their upperparts, and females have a buffier appearance on the head, throat, and breast.

Habitat

The Moustached Antwren is typically found in the canopy and subcanopy of lowland evergreen forests, with a preference for forest edges, gaps created by fallen trees, and areas along watercourses. The nominate subspecies also inhabits mature secondary forests, while in the Amazon Basin, M. i. obscura frequents both terra firme and várzea forests.

Distribution

This species has a disjunct distribution across several South American countries, including Brazil, Colombia, Ecuador, Panama, and Peru. Its range extends from Panama through northern Colombia and into northwestern Ecuador, with subspecies M. i. obscura found from south-central Colombia to northeastern Peru and into west-central Brazil.

Behaviour

The Moustached Antwren is believed to be a permanent resident within its range. It forages actively for arthropods, particularly insects and spiders, from the forest's mid-storey to the canopy, often joining mixed-species feeding flocks.

Song & Calls

The song of the Moustached Antwren is an accelerating series of short notes that rise and fall in pitch and intensity. Its call is a short, uneven, downslurred whistle, and the subspecies M. i. obscura also emits an abrupt note.

Breeding

Breeding behavior is largely unknown, but a nest observed in Peru was a pouch made of lichen and spiderweb, suspended from slender twigs and constructed by both members of a pair.

Conservation Status

The IUCN has classified the Moustached Antwren as Least Concern. Despite its large range and presence in several protected areas, the population size is unknown and believed to be decreasing. No immediate threats have been identified, but potential future threats include intensified oil exploration and associated road-building and human colonization in Ecuador, as well as the completion of the Pan-American highway in Panama-Colombia.