Citronella mucronata, the huillipatagua (pronounced as /es/), naranjillo, or Chilean citronella tree, is an evergreen tree endemic to Chile. It grows in the Chilean matorral region of central Chile from 30º to 40° south latitude.
It reaches up to 10 m (30 ft) and 1 m (3 ft) in diameter. The bark is dark gray and rough. The leaves are alternate, leathery, the edge is entire or toothed, ovate or oblong with an acute apex (tip) which ends in a mucro (sharp point). The leaves are about 4.5–6 cm long and 2.5–4 cm wide, with domatia in the axils of the side veins, and the veins are yellow, the leaves are glossy green above, and paler below. Small petioles. The flowers are hermaphrodite and whitish yellow and arranged in terminal panicles 4–8 cm long. The calyx is made up by 5 sepals, the corolla has 5 free petals. The fruit is a spherical drupe about 1–1.2 cm in diameter which is purple when mature.
Citronella mucronata is native to the Mediterranean climate Chilean matorral ecoregion, and grows discontinuously from Limari Province (30°40’S) to Osorno Province (40°30’S), between 15 and 1,050 meters elevation. It is common in the Chilean Coastal Range, and less common to the east in the foothills of the Andes.
It generally grows in sclerophyllous forest, most frequently in the Roble–Hualo forest type, where it can grow with Nothofagus dombeyi and Nothofagus alpina depending on the latitude. In northern coastal habitats it is often associated with Aextoxicon punctatum, Beilschmiedia miersii, Cryptocarya alba, and Schinus latifolia. In Los Bellotos del Melado National Reserve in the Andes it grows with Beilschmiedia berteroana, Cryptocarya alba, Nothofagus glauca, and Quillaja saponaria.
Although Citronella mucronata has an extensive north–south range, it is threatened by the extensive habitat loss which has occurred throughout its range, particularly in the Coastal Range where deforestation and habitat fragmentation are severe. Subpopulations of the species are increasingly isolated from one another, with the longest distance between them 122 km (Fray Jorge National Park and Los Vilos).