Tropidia (plant)


Tropidia, commonly known as crown orchids, is a genus of about thirty species of evergreen terrestrial orchids in the family Orchidaceae. They have thin, wiry stems with two or more tough, pleated leaves with a flowering spike at the top of the stem, bearing crowded flowers. Species in this genus are distributed across the warmer parts of both the Eastern and Western Hemispheres.

Description

Orchids in the genus Tropidia are evergreen, terrestrial, sometimes mycotrophic herbs which form small clumps. They have thin, wiry stems, sometimes with a few branches. The stems have two or more thin, tough, pleated, lance-shaped to egg-shaped leaves. Crowded white, greenish or brown, sometimes resupinate flowers are arranged on the top of the stem and have the sepals and petals free from each other, or with the lateral sepals joined and surrounding the base of the labellum. The labellum is not lobed but has a pouch or spur at its base.

Taxonomy and naming

The genus Tropidia was first formally described in 1833 by John Lindley and the description was published in Edwards's Botanical Register. The name Tropidia is derived from the Ancient Greek word tropidos or tropideion meaning "keel", referring to the boat-shaped labellum of some species in this genus.

Distribution and habitat

Species in the genus Tropidium grow in deep shade in evergreen monsoon forests and are native to China, Japan, the Indian subcontinent, Indonesia, Indochina, Philippines, New Guinea, Australia, Latin America, the West Indies, Florida, and some Pacific Islands including the Solomons, Fiji, New Caledonia, the Galápagos and Vanuatu.

Species

The following is a list of species of Tropidia recognised by Plants of the World Online as at October 2025:Tropidia angulosa Blume - Guangxi, Taiwan, Tibet, Yunnan, Bhutan, India, Assam, Bangladesh, Java, Sumatra, Japan, Malaysia, Myanmar, Thailand, VietnamTropidia bambusifolia Trimen - southern India, Sri Lanka, Andaman IslandsTropidia capitata OrmerodTropidia connata J.J.Wood & A.L.Lamb - SabahTropidia corymbioides Schltr. - New GuineaTropidia curculigoides Lindl. - widespread across southern China, the Himalayas, the Andaman Islands, Indochina, much of Indonesia, New Guinea, New Caledonia, and the Northern Territory of AustraliaTropidia disticha Schltr. - New Guinea, Solomons, BismarcksTropidia effusa Rchb.f. - Fiji, SamoaTropidia emeishanica K.Y.Lang - SichuanTropidia formosana Rolfe ex Hemsl.Tropidia gracilis Schltr. - New GuineaTropidia hegderaoi S.MisraTropidia janowskyi J.J.Sm. - New GuineaTropidia kjellbergii Ormerod & JuswaraTropidia maxwellii OrmerodTropidia mindanaensis Ames - MindanaoTropidia mindorensis Ames - MindoroTropidia multiflora J.J.Sm. - SumbaTropidia multinervis Schltr. - New GuineaTropidia nagamasui Ormerod & JuswaraTropidia namasiae C.K.Liao, T.P.Lin & M.S.Tang.Tropidia nipponica Masam. - Japan, Taiwan, Ryukyu Islands