''Osa pulchra'' is a species of rare flowering plant in the

monotypic In biology, a monotypic taxon is a taxonomic group (taxon) that contains only one immediately subordinate taxon. A monotypic species is one that does not include subspecies or smaller, infraspecific taxa. In the case of genera, the term "unisp ...

genus ''Osa'', belonging to the family

Rubiaceae Rubiaceae () is a family (biology), family of flowering plants, commonly known as the coffee, madder, or bedstraw family. It consists of terrestrial trees, shrubs, lianas, or herbs that are recognizable by simple, opposite leaves with Petiole ( ...

. There are only two known populations in

Costa Rica Costa Rica, officially the Republic of Costa Rica, is a country in Central America. It borders Nicaragua to the north, the Caribbean Sea to the northeast, Panama to the southeast, and the Pacific Ocean to the southwest, as well as Maritime bo ...

, with less than a total of thirty individual plants and a small population in

Panama Panama, officially the Republic of Panama, is a country in Latin America at the southern end of Central America, bordering South America. It is bordered by Costa Rica to the west, Colombia to the southeast, the Caribbean Sea to the north, and ...

. The genus name is derived from that of the

Osa Peninsula The Osa Peninsula () is a peninsula located in southwestern Costa Rica, in the Puntarenas Province, with the Pacific Ocean to the west and the Gulf of Dulce, Golfo Dulce to the east. The peninsula was formed geologically by a Geologic fault, faul ...

in southwestern Costa Rica. The plant is a shrub or small tree and has been cultivated in several botanical gardens, including

Kew Gardens Kew Gardens is a botanical garden, botanic garden in southwest London that houses the "largest and most diverse botany, botanical and mycology, mycological collections in the world". Founded in 1759, from the exotic garden at Kew Park, its li ...

, the

New York Botanical Garden The New York Botanical Garden (NYBG) is a botanical garden at Bronx Park in the Bronx, New York City. Established in 1891, it is located on a site that contains a landscape with over one million living plants; the Enid A. Haupt Conservatory, ...

, and the

Huntington Botanical Garden Huntington University is a Private university, private Christian university in Huntington, Indiana. It is affiliated with the Church of the United Brethren in Christ and a member of the Council for Christian Colleges and Universities (CCCU). ...

Description

''Osa pulchra'' has large white, trumpet-shaped, pendulous flowers reminiscent of those of certain

Solanaceous Solanaceae (), commonly known as the nightshades, is a family of flowering plants in the order Solanales. It contains approximately 2,700 species, several of which are used as agricultural crops, medicinal plants, and ornamental plants. Many mem ...

genera - particularly those of ''

Brugmansia ''Brugmansia'' is a genus of seven species of flowering plants in the nightshade family Solanaceae. They are woody trees or shrubs, with pendulous flowers, and have no spines on their fruit. Their large, fragrant flowers give them their common n ...

'' and '' Solandra''. The flowers are pendent, borne on long

pedicel Pedicle or pedicel may refer to: Human anatomy *Pedicle of vertebral arch, the segment between the transverse process and the vertebral body, and is often used as a radiographic marker and entry point in vertebroplasty and kyphoplasty procedures ...

s and feature fused petals borne upon slender, elongate corolla tubes. The blooms are highly fragrant at night and are most likely pollinated by bats (

chiropterophily Pollination syndromes are suites of flower traits that have evolved in response to natural selection imposed by different pollen vectors, which can be abiotic (wind and water) or biotic, such as birds, bees, flies, and so forth through a proces ...

Conservation

It is considered to be an endangered species by the IUCN Red List of threatened species.

Cultivation

This species is highly coveted because of its ornamental value. It needs a warm and humid climate with a well drained substrate and bright, indirect light. The plant is most easily propagated by seed, since cuttings can only be taken from the top of the plant due to

apical dominance In botany, apical dominance is the phenomenon whereby the main, central stem of the plant is dominant over (i.e., grows more strongly than) other side stems; on a branch the main stem of the branch is further dominant over its own side twigs. P ...

. Seeds will germinate after one month, after which it takes three more weeks for them to emerge fully from the substrate and shed their seed coats.

References

{{Taxonbar, from1=Q15482060, from2=Q9053384 Flora of Costa Rica Flora of Panama Chiococceae