The Prevost's Ground-Sparrow or White-faced Ground-Sparrow, Melozone biarcuatum, is an American sparrow which breeds at middle altitudes from southern Mexico to western Honduras and in Costa Rica. The isolated Costa Rican form may be a separate species, M. cabanisi.
This bird is found typically at altitudes between 600 and 1600m in the undergrowth and thickets of semi-open woodland, coffee plantations, hedgerows and large gardens. The nest, built by the female, is a neat lined cup constructed less than 2 m up in a bush or large tussock. The female lays two or three ruddy-blotched white eggs, which she incubates for 12-14 days. The male helps in feeding the chicks. This species is sometimes parasitised by the Bronzed Cowbird.
The Prevost's Ground-Sparrow is on average 15 cm long and weighs 28 g. The adult has a stubby dark-grey bill, unstreaked olive-brown upperparts, a rufous crown and mainly white underparts.
The northern form has a simple head pattern in which the rufous of the crown extends down the sides of the neck as a half collar behind the white face.
In the Costa Rican subspecies, the rufous of the crown extends to behind the eye and is bordered on its anterior edge with black This black border is broken by a white eye ring. The forehead is white, bordered below with a thin black line, there is a black malar stripe, and a black central breast patch.
Young birds are browner above, have yellower underparts, and a duller indistinct head pattern.
Prevost's Ground-Sparrow calls include a thin tsit or a clearer psee. The male's song, given from a hidden perch in the wet season, is a whistled pst't't't peer peer peer whee whee whee.
The Prevost's Ground-Sparrow feeds on the ground on seeds, fallen berries, insects and spiders. It is usually in pairs, but is a shy species best seen at near or dusk.
This species' English name commemorates French naturalist Florent Prévost , and the scientific name of the Costa Rican subspecies refers to German ornithologist Jean Cabanis.