Even before the split the species had a complicated taxonomic history, being variously assigned to genera Hypocnemis, Hylophylax, and Dichropogon before the current Willisornis was created for it.

[3][9][10] However, BirdLife International's Handbook of the Birds of the World (HBW) treats the two taxa as separate species, respectively called the Xingu and Tapajos scale-backed antbirds.

Both sexes have a grayish iris, a black bill, and pale gray legs and feet.

[12][13] The Xingu scale-backed antbird is found in south-central and eastern Amazonian Brazil south of the Amazon River.

Subspecies W. v. nigrigula occurs further west, between the rios Tapajós and Xingu and south into northern Mato Grosso state.

It captures prey mostly by short sallies from a perch to the ground but also to foliage, branches, and vines.

The Xingu scale-backed antbird's song is "a series of long upslurred notes, which are frequency-modulated in an even pattern".

Its calls include "a twitter formed by a short...high-pitched series of clear, almost tinkling, musical notes that descends slightly in frequency", "a descending chirr", and a "raspy series of 3–4 cheery, cheery, churry, churry notes".

Though its range includes several large protected areas, the eastern parts "have been subject to extensive and ongoing deforestation and fragmentation during recent decades".