Comparettia is a genus of orchids in the family Orchidaceae (order Asparagales), comprising approximately 50–70 species of small to medium epiphytic plants native to tropical America. The genus is abbreviated "Comp" in the horticultural trade. Plants in the genus are typically small, caespitose epiphytes or occasional lithophytes, growing on shrubs, tree trunks, and branches in wet montane forests. They bear oblong to cylindric pseudobulbs, each carrying a single narrow, elliptic to lanceolate leaf. Inflorescences arise from the base of a newly matured pseudobulb and are erect to arching racemes, sometimes loosely branched, bearing several brightly coloured flowers held well above the foliage.
The genus is distributed from Mexico and Central America through the Caribbean islands and into northern South America, reaching as far south as Brazil and Bolivia. Species are most abundant and diverse in the Andean region of South America, where they occur across a wide altitudinal range from warm lowland forests to cool montane habitats up to approximately 3000 m elevation.
Comparettia has expanded substantially in recent decades as molecular phylogenetic revisions led to the transfer of many species from related genera such as Ionopsis and others within the Oncidiinae subtribe. As a result the species count and circumscription of the genus continues to be updated. Notable species include Comparettia falcata, one of the most widely distributed members of the genus, and Comparettia macroplectron, well known in cultivation for its showy flowers.
Distribution
Comparettia species are native to tropical America, occurring from Mexico and Central America through the Caribbean (including Cuba, Jamaica, Puerto Rico, Hispaniola) and across northern South America to Brazil and Bolivia. The genus reaches its greatest diversity in the Andes, where species occur from warm lowland valleys at around 200 m to cool cloud-forest elevations approaching 3000 m.
Ecology
Members of Comparettia grow primarily as epiphytes on small branches, shrubs, and low tree trunks in wet montane forests, and occasionally as lithophytes on rocky substrates. The wide altitudinal range documented for C. falcata (200–3000 m) reflects the genus's tolerance of both warm and cool conditions, making many species amenable to cultivation across a broad temperature range.
Cultivation
Comparettia species are grown by orchid enthusiasts for their bright, often scarlet or pink flowers. Being small epiphytes they are well suited to basket or mounted culture with good air circulation and regular watering during the growing season, with a slight reduction in water after pseudobulbs mature. Most species prefer intermediate to cool temperatures reflecting their Andean origin.
