A 16-cm ground-tyrant with uniformly gray appearance, the plainest species in the genus. Shows a very faint whitish eyebrow, slightly dark loral area, and completely lacks a nuchal patch—an essential feature to distinguish it from most other ground-tyrants. Upperparts pale ash-gray, wings darker and more contrasting; tail blackish with a thin white outer margin. Underparts whitish-gray with slight darkening on the chest flanks. Bill and legs black. Although it coexists with other Muscisaxicola species, it is easily recognized by its uniform gray coloration and lack of a nuchal patch.
Geographical distribution: Andean species occurring from southern Peru, western Bolivia, northern and central Chile, and northwestern Argentina south to Río Negro between 2,500–4,500 m, occasionally higher and locally descending to 1,000 m. Performs altitudinal and latitudinal migration: southern and Chilean/Argentine populations move toward Bolivia and southern Peru in winter. Some individuals may be resident in NW Argentina. Particularly common in PP Cumbres Calchaquíes, Tucumán.
Subspecies in Argentina:
Argentinus: NW Argentina (Jujuy, Salta, Tucumán, Catamarca, La Rioja), slightly paler and browner.
Cinereus: Mendoza, Río Negro.
Habitat: Stony grasslands, shrub-steppe, rocky outcrops and margins of high-Andean lakes. Uses open areas with rocky exposures, scattered low vegetation and gravel.
Behavior: Terrestrial and relatively tame. Walks or runs in search of prey; perches on rocks or low shrubs and repeatedly bobs its tail up and down, always holding an erect posture. Seen alone or in pairs; outside the breeding season may form small groups and mix with other ground-tyrants. Very reduced vocalizations, only a short dry “pip”.
Diet: Terrestrial and flying arthropods captured on the ground after short runs and jumps; occasionally fruits and small vertebrates.
Nesting: Nests in crevices, caves, and rocky outcrops. Clutch of 2–3 eggs. Both adults feed nestlings and fledglings.
Conservation status: Species not considered threatened. Fairly common within its range.
Authors of this compilation: Diego Carus and Maria Belén Dri – 06/12/2025