Corymborkis is a genus of terrestrial, evergreen orchids in the family Orchidaceae (order Asparagales), commonly known as cinnamon orchids. The genus comprises eight currently accepted species and was first formally described in 1809 by the French botanist Louis-Marie Aubert du Petit-Thouars, in the Bulletin de la Société philomathique de Paris.
Plants in this genus grow in clumps from short rhizomes, producing one or more thin, wiry, unbranched stems. The stems bear many papery, pleated leaves, egg-shaped to elliptic in outline, clustered toward the upper half of the plant. A branching flowering stem develops from the upper leaf axils, carrying crowded, widely-opening flowers. The flowers are greenish white, with thin, spreading sepals and petals that are similar in shape to one another, the petals slightly wider than the sepals. The labellum is roughly as long as the sepals and closely surrounds the reproductive column; it has a tube-like base and two longitudinal ridges running along its length — a distinctive feature used to separate Corymborkis from related terrestrial orchid genera.
Corymborkis is widely distributed across the tropics, with a range spanning tropical Africa, India, Sri Lanka, Thailand, Malaysia, the Philippines, Indonesia, New Guinea and Australia (including Christmas Island), while other species of the genus occur across South and Central America and parts of the Caribbean. Within this range, plants are generally found growing in moist, shady sites on the floor of rainforest, reflecting a preference for humid, low-light forest-understorey conditions typical of many terrestrial orchids.
Taxonomically, GBIF places the genus in the family Orchidaceae and order Asparagales, consistent with its recognized authorship (Thouars) and 1809 publication date. The genus's broad tropical, disjunct distribution — spanning both the Old World and the New World tropics — makes it of biogeographic interest among terrestrial orchid genera.
Etymology
The name Corymborkis combines the Ancient Greek words korymbos ("bunch of flowers or fruit") and orchis ("testicle" or "orchid"), referring to the bunched arrangement of the genus's flowers.
Distribution
Corymborkis is widely distributed across the tropics, occurring in tropical Africa, India, Sri Lanka, Thailand, Malaysia, the Philippines, Indonesia, New Guinea and Australia (including Christmas Island), with other species extending the genus's range into South America, Central America and the Caribbean.
Ecology
Plants in this genus are terrestrial and typically grow in moist, shady places on the floor of rainforest.
Taxonomy Notes
The genus was first formally described in 1809 by Louis-Marie Aubert du Petit-Thouars, published in the Bulletin de la Société philomathique de Paris (Nouv. Bull. Sci. Soc. Philom. Paris 1: 318). GBIF places it in family Orchidaceae, order Asparagales; Wikipedia recognizes eight accepted species, while GBIF's backbone lists 24 descendant taxa (a broader count that includes synonyms).
