Apurímac Spinetail

The Apurimac spinetail is 17 to 18 cm (6.7 to 7.1 in) long and weighs about 15 g (0.53 oz). The sexes have the same plumage. Adults have a pale gray supercilium on an otherwise dark gray face. Their forecrown is dark gray, their hindcrown and nape dark rufous, and their back, rump and uppertail coverts dark gray with a faint olivaceous tinge. Their wings are rufous with dark brown tips on the flight feathers. Their tail is dark sooty brown with a hint of rufous; the tail is very long and graduated, and the feathers have slightly pointed tips. Their throat is sooty black with pale gray edges to the feathers. Their breast, belly, and undertail coverts are dark gray; their flanks are dark gray with a faint olivaceous wash. Their iris is dark chestnut, their maxilla black or dark gray, their mandible bluish gray with a black tip, and their legs and feet dark gray.

The Apurimac spinetail has a very small range in south-central Peru, on the slopes of Ampay, a large mountain southwest of the Apurimac River. Much, but not all, of its known area of occurrence is within Ampay National Sanctuary. It inhabits cloudforest, humid Podocarpus forest, and regrowing vegetation in clearings and landslide scars. It favors dense understory and stands of Chusquea bamboo. In elevation it occurs between 2,450 and 3,500 m (8,000 and 11,500 ft).

The Apurimac spinetail feeds on arthropods, though details of its diet are lacking. It typically forages singly or in pairs and occasionally joins mixed-species feeding flocks. It gleans prey from moss, lichen, small branches, and foliage, typically in dense cover near or on the ground.