Ambrella longituba

Ambrella longituba is a small epiphytic orchid and the only species of the monotypic genus Ambrella, endemic to northern Madagascar. It was collected and described by Joseph Marie Henry Alfred Perrier de la Bathie in 1934. The plants are relatively small, but the flowers are big in proportion to them: the sepals are free and resemble the petals, and the unusual labellum is a tube about 45 mm long with a spur, enclosing the column, with the inner surface of the tube covered in trichomes. The orchid grows in the semi-dry forests of the northern tip of Madagascar at about 800 m above sea level, usually on branches of the tree Viguieranthus alternans, its preferred host. Its pollinators are unknown, though Perrier de la Bathie suggested that the narrow labellum tube admits only a few specialised insects, which would explain the rarity of the species. Flowering occurs in November. Only five records are known, dating from 1932 to 1995, and the species is listed in CITES Appendix II. The epithet longituba means long trumpet and refers to the shape of the labellum.