Cinereous Mourner

The cinereous mourner is 20 to 21 cm (7.9 to 8.3 in) long and weighs 41 to 51 g (1.4 to 1.8 oz). The sexes have the same plumage. Adults have a thin orange ring around the eye. The rest of their head, upperparts, wings, and tail are mostly gray. Their primaries have a brown tinge and two rows of cinnamon spots that show as broken wing bars. Their tertials and the tips of their tail feathers have smaller cinnamon spots. Their underparts are a slightly paler gray than their upperparts. Their breast and crissum sometimes have black-tipped orange spots. They have pectoral tufts that are often hidden; in one variant the tufts are orange and in a second one they are pale yellow. Both variants have a dark iris, a dark bill, and gray legs. Nestlings of this species are orange with long filoplumes that end in white tips and have a resemblance to hairy caterpillars of a moth belonging to the family Megalopygidae. The young birds move their heads slowly from side to side which are thought to enhance the impression by resembling a moving caterpillar. It is thought that this may be the first case of Batesian mimicry involving a harmless bird mimic and a toxic insect model, although another species, the Brazilian laniisoma (Laniisoma elegans), also has young that share a similar downy appearance; however, detailed observations of the latter are unavailable.

The cinereous mourner is found throughout the entire Orinoco River and Amazon River basins with a disjunct population in eastern Brazil. Its main range spans from southeastern Colombia south through eastern Ecuador and eastern Peru into northwestern Bolivia. From there it extends east across southern and eastern Venezuela and the Guianas and all of Amazonian Brazil. The isolated population is found in southeastern Bahia and northern Espírito Santo. The cinereous mourner primarily inhabits humid terra firme and igapó forest. It seems to favor sloping terrain and areas near ravines. In some areas it also occurs in forest on sandy soil and in woodlands in savanna. In elevation it occurs up to 600 m (2,000 ft) in Colombia, mostly up to 400 m (1,300 ft) in Ecuador, up to 900 m (3,000 ft) in Peru, and up to 500 m (1,600 ft) in Venezuela.

The cinereous mourner feeds on arthropods and fruit. It forages from the forest's understory to its midstory, usually singly, and sometimes joins mixed-species feeding flocks. It perches silently and makes short sallies, sometimes with a brief hover, to glean from foliage or branches.