Formerly called Sennett's Warbler, Olive-backed Warbler, Pitiayumi Warbler, and Tropical Parula Warbler, the Tropical Parula is one of several species of birds whose breeding range in North America is restricted to extreme southern Texas. This species occupies a wide latitudinal range—through Mexico and Central and South America as far south as northern Argentina. It is resident throughout much of its range, although northernmost populations (including southern Texas) are at least partially migratory. A small active bird of the forest canopy, the Tropical Parula is heard more often than seen. It is a persistent singer that feeds mainly on insects and other arthropods that it gleans from foliage. Its domed nest is hollowed out of a mass of epiphytic plants, such as Spanish moss (Tillandsia usneoides).
The Tropical Parula is closely related to the Northern Parula, and the two have been considered one species. Recent genetic data, however, indicate that the Northern and Tropical parulas are sister taxa derived within the genus Setophaga. The species name, pitiayumi, is derived from a Guarani (Paraguayan) name meaning “little yellow chest” ( Jobling 1991 ). Details of its life history are poorly documented, especially in South America. Considerable research is necessary to fill in the large gaps in our knowledge of this enigmatic species.