The pyrrhuloxia /ˌpɪrəˈlɒksiə/ or desert cardinal (Cardinalis sinuatus) is a medium-sized North American songbird found in the American southwest and northern Mexico. This distinctive species with a short, stout bill and red crest and wings, and closely resembles the northern cardinal and the vermilion cardinal, which are in the same genus.

The desert cardinal is one of three birds in the genus Cardinalis in the family Cardinalidae, a group of passerine birds found in North and South America.

Its name of pyrrhuloxia – once part of its scientific name – comes from Greek terms describing its coloration (πυρρος = pyrrhos = reddish or orange) and the shape of its bill (λοξος = loxos = oblique). The common name, desert cardinal, refers to it inhabiting the southwest, and often arid regions, of the North American continent.

The desert cardinal is a medium-sized song bird; the length for both sexes is about 8.3 in (21 cm), while the typical weight is 0.8–1.5 oz (24–43 g).

The most obvious differences between the male desert cardinal and the northern cardinal are in their coloring. The desert cardinal is predominantly brownish-gray with a red breast, a red mask, and a yellow, parrot-like bill that is stout and rounded. The females of the two species resemble each other much more closely, but the shapes of their bills are diagnostic. The songs of the two species are identical, though the pyrrhuloxia's is not quite as loud. This cardinal retains the distinctive long, pointed, red crest present in all species.

The pyrrhuloxia is a year-round resident of desert scrub and mesquite thickets, in the U.S. states of Arizona, New Mexico, and Texas and woodland edges in Mexico. It occupies the southwestern half of Texas, roughly the southern third of New Mexico, and southeastern region of Arizona. Its range includes areas from the west to east coast of Mexico north of the Sierra Madre del Sur, Trans-Mexican Volcanic Belt, and Isthmus of Tehuantepec, while excluding the Sierra Madre Occidental. An individual of the species has reportedly been seen as far away from its dominant range as Costa Mesa, California, in Orange County.

This cardinal is relatively nonmigratory, though it may occasionally stray slightly north of its usual range. The pyrrhuloxia prefers habitat along stream beds. In areas where the range of the pyrrhuloxia and northern cardinal overlap, hybridization may occur between them.

In breeding season, songs are used to establish and defend territories. One song has a sharp, clear, "wha-cheer, wha-cheer", while another is characteristic of a metallic "quink". Females also sing, but they use softer and duller notes. A short "cheep" or "chip" is a regular contact call given by both sexes while foraging.