Pomatocalpa, commonly known as bladder orchids, or 鹿角兰属 (lu jiao lan shu), is a genus of about twenty five species from the orchid family, Orchidaceae. Plants in this genus are epiphytes or lithophytes with thick, leathery leaves and a large number of small flowers with a three-lobed labellum. There are about twenty five species found from tropical and subtropical Asia to the south-west Pacific.
Description Orchids in the genus Pomatocalpa are monopodial epiphytic or lithophytic herbs with long, thick roots attached to the substrate, with fibrous stems and long-lasting leaves arranged in two rows with their bases obscuring the stems. A large number of relatively small flowers are arranged on a panicle or raceme and with sepals and petals that are similar to each other and a labellum that has three lobes.
Taxonomy and naming The genus Pomatocalpa was first formally described in 1829 by Breda in Genera et Species Orchidearum et Asclepiadearum. The type species is Pomatocalpa spicatum. The name Pomatocalpa is derived from the Ancient Greek words pomatos meaning "cover", "lid", "operculum" or "gill-cover" and kalpe meaning "vessel for drawing water", "pitcher" or "urn", referring to the deeply pouched labellum.
Species The following is a list of species accepted by the Plants of the World Online as at October 2025: Pomatocalpa angustifolium Seidenf. - Thailand, Vietnam Pomatocalpa arachnanthe (Ridl.) J.J.Sm. - Malaysia Pomatocalpa armigerum (King & Pantl.) Tang & F.T.Wang - Assam, Bhutan Pomatocalpa bambusarum (King & Pantl.) Garay - Assam, Bhutan Pomatocalpa bhutanicum N.P.Balakr. - Bhutan Pomatocalpa bicolor (Lindl.) J.J.Sm. - Philippines Pomatocalpa decipiens (Lindl.) J.J.Sm. - India, Bangladesh, Sri Lanka Pomatocalpa diffusum Breda - Thailand, Malaysia, Indonesia, Philippines Pomatocalpa floresanum J.J.Sm. - Flores Pomatocalpa fuscum (Lindl.) J.J.Sm. - Malaysia, Borneo, Philippines Pomatocalpa grande Seidenf. - Vietnam Pomatocalpa koordersii (Rolfe) J.J.Sm. Pomatocalpa kunstleri (Hook.f.) J.J.Sm. - Thailand, Malaysia, Indonesia, Philippines Pomatocalpa linearipetalum J.J.Sm. - Seram Pomatocalpa macphersonii - New Guinea, Queensland Pomatocalpa maculosum (Lindl.) J.J.Sm. - widespread from Sri Lanka and Bhutan to Java and the Philippines Pomatocalpa maculosum subsp. andamanicum (Hook.f.) Watthana Pomatocalpa maculosum subsp. maculosum Pomatocalpa marsupiale (Kraenzl.) J.J.Sm. - Queensland, Maluku, Sulawesi, New Guinea, Solomons, Vanuatu Pomatocalpa parvum (Ridl.) J.J.Sm. - Pahang Pomatocalpa simalurense J.J.Sm . - Simeuluë Pomatocalpa sphaetophorum (Schltr.) J.J.Sm. - Borneo Pomatocalpa spicatum Breda, Kuhl & Hasselt - Hainan, Assam, Bhutan, Andaman & Nicobar Islands, Indochina, Malaysia, Indonesia, Philippines Pomatocalpa tonkinense (Gagnep.) Seidenf. - Vietnam, Laos Pomatocalpa truncatum (J.J.Sm.) J.J.Sm. - Borneo Pomatocalpa undulatum (Lindl.) J.J.Sm - Assam, Bangladesh, Taiwan Pomatocalpa undulatum subsp. acuminatum (Rolfe) Watthana Pomatocalpa undulatum subsp. undulatum
Distribution Species in the genus Pomatocalpa are found from tropical and substropical Asia to the southwest Pacific.
See also List of Orchidaceae genera
References