Slaty Gnateater

The slaty gnateater is 12.5 to 14 cm (4.9 to 5.5 in) long, and 57 specimens had a mean weight of 26.3 g (0.93 oz). The plumage is variable, but the typical male's head is mostly dark gray that continues through most of the underparts. The crown and upper parts are brown and the flanks and lower belly are brownish gray. It has a white tuft behind the eye. Birds in the Cochabamba Department of Bolivia are much darker. The female has more brown on the face, the white tuft is much smaller, and there is a white patch on the belly. The upper parts can be dark brown, olive brown, or rufous brown.

The slaty gnateater inhabits the narrow band of the Yungas on the eastern slope of the Andes. C. a. saturata is found in Peru from southeastern Cusco Province south towards Bolivia. C. a. ardesiaca is found from the Department of Puno in southeastern Peru to Bolivia's Tarija Department. The species inhabits dense growth in rainforest, typically around treefalls, road edges, and similar openings. In elevation it typically ranges from 800 to 1,800 m (2,600 to 5,900 ft) but is found locally to 2,450 m (8,040 ft) in Peru.

The slaty gnateater forages for arthropods in leaf litter and foliage on and near the ground.