It is found in South America, in humid subtropical and tropical savanna climates in most of the countries east of the Andes: Venezuela, Brazil, Bolivia, Paraguay, Uruguay, and Argentina.

The species, which is closely related to becards and tityras, was thought to be either a tyrant-flycatcher or cotinga, before it was placed in Tityridae.

The species is not common and little is known about it, but it is not considered in danger of extinction, and has been classified as of least concern by the International Union for Conservation of Nature.

The white-naped xenopsaris was described in 1869 by the German-Argentine scientist Hermann Burmeister, based on a specimen collected near Buenos Aires.

A 1989 study of anatomy identified Pachyramphus as a sister taxon to Xenopsaris,[3] but the white-naped xenopsaris was kept in its own genus due to several morphological and behavioural differences, namely its smaller size, the shape of its legs, the length of its primary flight feathers, the lack of strong sexual dimorphism (differences between the sexes) and the construction of the nest.

According to the Handbook of the Birds of the World, Xenopsaris and its allies were "taxonomically problematic genera that have for more than a hundred years been shifted back and forth between the cotingas (Cotingidae) and the Tyrannidae".

[4] When placed with the tyrant-flycatchers, Tyrannidae, it was considered closely related to the genera Suiriri, Serpophaga and Knipolegus.

[6] A 2007 study of mitochondrial DNA confirmed the white-naped xenopsaris' place in the Tityridae, and its close relationship to Pachyramphus, as well as the genus Tityra.

[2] The white-naped xenopsaris is smaller than the closely related becards and tityras, measuring 12.5 to 13 cm (4.9–5.1 in) in length and weighing around 10 g (0.35 oz).

Juvenile birds resemble adults but have greyish napes and more chestnut in the crown,[2] and the feathers of the back, rump and primaries are scalloped with ochre.

The call is described as a thin, high-pitched and hesitant "teep, tre'e'e'e'e'a eea wu'u'u'e'e'e-e-e-e-e-p" or a "twip, tsiweeé, tseee, ti-ti-ti-ti", according to the Handbook of the Birds of the World.

The white-naped xenopsaris is smaller, with a longer tail, thinner bill, whiter underparts (instead of grey) and browner upperparts (rather than greyish) .

The southern population of the nominate subspecies is widespread from north-eastern Brazil through to Bolivia, Paraguay and northern Argentina and Uruguay.

[14] A study published in 2005 suggested it was migratory in Santa Fe, Argentina, as the species was not observed in the area between March and September (the austral winter).

Chicks in the nest are fed grasshoppers from the family Acrididae, mantidflies, praying mantises and mosquitoes.

[12] Nesting timing varies by location; in Venezuela it is reported to occur during the rainy season (June to September),[15] and in Argentina during the austral summer (October to January).

Nests have been recorded being constructed from fine dry grass,[13] or woven plant fibre and a few rootlets.