Calanthe, commonly known as Christmas orchids, is a genus of about 220 species of orchids in the family Orchidaceae. They are evergreen or deciduous terrestrial plants with thick roots, small oval pseudobulbs, large corrugated leaves and upright, sometimes arching flowering stems. The sepals and petals are narrow and a similar size to each other and the labellum usually has spreading lobes.
Description Orchids in the genus Calanthe are terrestrial with small, crowded pseudobulbs with thick roots and a few corrugated or wrinkled leaves with the base tapering to a petiole-like stalk. Some species are evergreen while others are deciduous. The flowers are delicate but showy, white, pink, yellow or orange and crowded near the end of an erect, sometimes arching flowering stem. The sepals and petals are relatively narrow, similar in size and spread widely. The labellum has three or four spreading lobes and in most species there is a spur at the base. Unlike similar orchids, the labellum of Calanthe orchids is fused to the column.
Taxonomy and naming The genus Calanthe was first formally described in 1821 by Robert Brown and his manuscript was published in The Botanical Register. The name Calanthe is derived from the Ancient Greek words kallos meaning "beauty" and anthos meaning "flower".
Distribution and habitat Calanthe species are found in all tropical areas, but mostly concentrated in Southeast Asia. Some species also range into subtropical lands such as China, Indian subcontinent, Madagascar, Australia, Mexico, Central America, the West Indies and various islands of the Pacific and Indian Oceans.
List of species The following is a list of species of Calanthe recognised by the Plants of the World Online as at August 2018:
Calanthe abbreviata (Blume) Lindl. Calanthe aceras Schltr. Calanthe africana M.W.Chase, Christenh. & Schuit. Calanthe alba W.Suarez & Cootes Calanthe albolutea Ridl. Calanthe alismifolia Lindl. Calanthe alleizettei Gagnep. Calanthe alpina Hook.f. ex Lindl. Calanthe alta Rchb.f. Calanthe amboinensis (Blume) M.W.Chase, Christenh. & Schuit. Calanthe angustifolia (Blume) Lindl. Calanthe aquamarina Schuit. & de Vogel Calanthe arcuata Rolfe Calanthe arfakana J.J.Sm. Calanthe argenteostriata C.Z.Tang & S.J.Cheng Calanthe arisanensis Hayata Calanthe aristulifera Rchb.f. Calanthe aruank P.Royen Calanthe aurantiaca Ridl. Calanthe aureiflora J.J.Sm. Calanthe averyanoviana M.W.Chase, Christenh. & Schuit. Calanthe baconii (J.J.Sm. & Shim) M.W.Chase, Christenh. & Schuit. Calanthe balansae Finet Calanthe baliensis J.J.Wood & J.B.Comber Calanthe beamanii P.J.Cribb Calanthe beleensis Ormerod & P.J.Cribb Calanthe bicalcarata J.J.Sm. Calanthe biloba Lindl. Calanthe bingtaoi J.W.Zhai, L.J.Chen & Z.J.Liu Calanthe bivalvis P.J.Cribb & Ormerod Calanthe borneensis (J.J.Sm.) M.W.Chase, Christenh. & Schuit. Calanthe brassii Ormerod Calanthe brevicornu Lindl. Calanthe burkei P.J.Cribb Calanthe calanthoides (A.Rich. & Galeotti) Hamer & Garay in F.Hamer Calanthe callosa (Blume) M.W.Chase, Christenh. & Schuit. Calanthe camptoceras Schltr. Calanthe cardioglossa Schltr. Calanthe carrii Govaerts Calanthe caulescens J.J.Sm. Calanthe caulodes J.J.Sm. Calanthe ceciliae Rchb.f. Calanthe celebica Rolfe Calanthe chevalieri Gagnep. Calanthe chloroleuca Lindl. Calanthe chrysoglossoides J.J.Sm. Calanthe clavata Lindl. Calanthe clavicalcar J.J.Sm. Calanthe claytonii P.J.Cribb Calanthe coiloglossa Schltr. in K.M.Schumann & C.A.G.Lauterbach Calanthe columnaris (C.Z.Tang & S.J.Cheng) M.W.Chase, Christenh. & Schuit. Calanthe conspicua Lindl. Calanthe coodei P.J.Cribb Calanthe cooperi (Rolfe) M.W.Chase, Christenh. & Schuit. Calanthe cootesii Naive Calanthe corymboides (Schltr.) M.W.Chase, Christenh. & Schuit. Calanthe cremeoviridis J.J.Wood Calanthe crenulata J.J.Sm. Calanthe crispifolia Ormerod Calanthe cruciata Schltr. Calanthe crumenata Ridl. Calanthe crystallina P.J.Cribb Calanthe curvatoascendens Gilli Calanthe daenikeri (Kraenzl.) M.W.Chase, Christenh. & Schuit. Calanthe davaensis Ames Calanthe davidii Franch. Calanthe daymanensis Ormerod & P.J.Cribb Calanthe decora M.W.Chase, Christenh. & Schuit. Calanthe delavayi Finet Calanthe densiflora Lindl. Calanthe devogelii P.J.Cribb & D.A.Clayton Calanthe discolor Lindl. Calanthe dolichopoda Fukuy Calanthe dulongensis H.Li, R.Li & Z.L.Dao Calanthe duyana Aver. Calanthe ecalcarata (J.J.Sm.) M.W.Chase, Christenh. & Schuit. Calanthe ecallosa J.J.Sm. Calanthe ecarinata Rolfe ex Hemsl. Calanthe emeishanica K.Y.Lang & Z.H.Tsi Calanthe engleriana Kraenzl. in K.M.Schumann & C.A.G.Lauterbach Calanthe epiphytica Carr Calanthe fargesii Finet Calanthe ferruginea M.W.Chase, Christenh. & Schuit. Calanthe finisterrae Schltr. Calanthe fissa L.O.Williams Calanthe flava (Blume) C.Morren Calanthe floresana P.J.Cribb Calanthe forbesii Ridl. Calanthe formosana Rolfe Calanthe fragrans P.Royen Calanthe francoisii (Schltr.) M.W.Chase, Christenh. & Schuit. Calanthe fugongensis X.H.Jin & S.C.Chen Calanthe geelvinkensis J.J.Sm. Calanthe gibbsiae Rolfe Calanthe goodenoughiana Ormerod & P.J.Cribb Calanthe graciliflora Hayata Calanthe graciliscapa Schltr. Calanthe grandiflora Nadeaud Calanthe grata (Blume) M.W.Chase, Christenh. & Schuit. Calanthe griffithii Lindl. Calanthe gustavii M.W.Chase, Christenh. & Schuit. Calanthe habbemensis Ormerod & P.J.Cribb Calanthe hainanensis (C.Z.Tang & S.J.Cheng) M.W.Chase & Schuit. Calanthe halconensis Ames Calanthe hancockii Rolfe Calanthe hattorii Schltr. Calanthe hekouensis (Tsukaya, M.Najak. & S.K.Wu) M.W.Chase, Christenh. & Schuit. Calanthe henryi Rolfe Calanthe herbacea Lindl. Calanthe himalaicum Raskoti Calanthe hirsuta Seidenf. Calanthe hololeuca Rchb.f. in B.Seemann Calanthe hoshii S.Kobay. Calanthe humblotii (Rchb.f.) M.W.Chase, Christenh. & Schuit. Calanthe hyacinthina Schltr. Calanthe imthurnii Kores Calanthe indigofera (Hassk.) M.W.Chase, Christenh. & Schuit. Calanthe indochinensis (Seidenf. & Ormerod) M.W.Chase, Christenh. & Schuit. Calanthe inflata Schltr. Calanthe insularis S.H.Oh, H.J.Suh & C.W.Park Calanthe izu-insularis (Satomi) Ohwi & Satomi in J.Ohwi Calanthe johorensis Holttum Calanthe judithiae P.J.Cribb Calanthe jusnerii Boxall ex Náves in F.M.Blanco Calanthe kaniensis Schltr. Calanthe kemulensis J.J.Sm. Calanthe kermodei Ormerod & Kurzweil Calanthe keshabii Lucksom Calanthe kinabaluensis Rolfe Calanthe kooshunensis Fukuy. Calanthe labiata (J.J.Sm.) M.W.Chase, Christenh. & Schuit. Calanthe labrosa (Rchb.f.) Rchb.f. Calanthe lacerata Ames Calanthe laciniata (Ormerod) M.W.Chase, Christenh. & Schuit. Calanthe lambii P.J.Cribb Calanthe lamellosa Rolfe Calanthe lancilabris Ormerod & P.J.Cribb Calanthe landyae (P.J.Cribb & J.V.Stone) M.W.Chase, Christenh. & Schuit. Calanthe lechangensis Z.H.Tsi & Tang Calanthe leonidii P.J.Cribb & D.A.Clayton Calanthe leucosceptrum Schltr. Calanthe leuseri P.J.Cribb Calanthe ligo P.J.Cribb Calanthe limprichtii Schltr. Calanthe longgangensis Y.S.Huang & Yan Liu Calanthe longibracteata Ridl. Calanthe longicornu (Guillaumin) M.W.Chase, Christenh. & Schuit. Calanthe longifolia Schltr. Calanthe longipes Hook.f. Calanthe lutea (Ursch & Toill.-Gen. ex Bosser) M.W.Chase, Christenh. & Schuit. Calanthe lyonii (Ames) M.W.Chase, Christenh. & Schuit. Calanthe lyroglossa Rchb.f. Calanthe madagascariensis Rolfe ex Hook.f. Calanthe mannii Hook.f. Calanthe maquilingensis Ames Calanthe masuca (D.Don) Lindl. Calanthe maxii P.O'Byrne Calanthe mcgregorii Ames Calanthe metoensis Z.H.Tsi & K.Y.Lang Calanthe micrantha Schltr. Calanthe microglossa Ridl. Calanthe millikenii P.J.Cribb Calanthe millotae Ursch & Genoud ex Bosser Calanthe mindorensis Ames, Philipp. J. Sci. Calanthe mishmensis (Lindl. & Paxton) M.W.Chase, Christenh. & Schuit. Calanthe moluccensis J.J.Sm. Calanthe monophylla Ridl. Calanthe montana (Schltr.) M.W.Chase, Christenh. & Schuit. Calanthe morotaiensis (Ormerod & Juswara) Schuit. Calanthe musa-amanii J.J.Wood Calanthe nana (Hook.f.) M.W.Chase, Christenh. & Schuit. Calanthe nankunensis Z.H.Tsi Calanthe nguyenthinhii Aver. Calanthe nicolae P.O'Byrne Calanthe nipponica Makino Calanthe nivalis Boxall ex Náves in F.M.Blanco Calanthe obcordata (Lindl.) M.W.Chase, Christenh. & Schuit. Calanthe obreniformis J.J.Sm. Calanthe odora Griff. Calanthe okinawensis Hayata Calanthe oreadum Rendle Calanthe otuhanica C.L.Chan & T.J.Barkman Calanthe ovalifolia Ridl. Calanthe ovata Ridl. Calanthe parvilabris Schltr. Calanthe pauciflora (Blume) M.W.Chase, Christenh. & Schuit. Calanthe pauciverrucosa J.J.Sm. Calanthe pavairiensis Ormerod Calanthe perrottetii A.Rich. Calanthe petelotiana Gagnep. Calanthe peyrotii (Bosser) M.W.Chase, Christenh. & Schuit. Calanthe philippinensis (N.E.Br.) M.W.Chase, Christenh. & Schuit. Calanthe plantaginea Lindl. Calanthe poiformis P.J.Cribb & Ormerod Calanthe polyantha Gilli Calanthe puberula Lindl. Calanthe pulchella (Kraenzl.) M.W.Chase, Christenh. & Schuit. Calanthe pulchra (Blume) Lindl. Calanthe pullei J.J.Sm. Calanthe punctata Kurzweil Calanthe reflexilabris J.J.Sm. Calanthe reflexipetals (J.J.Wood & Shim) M.W.Chase, Christenh. & Schuit. Calanthe rhodochila Schltr. Calanthe rigida Carr Calanthe robertsii (F.Muell.) M.W.Chase, Christenh. & Schuit. Calanthe rosea (Lindl.) Benth. Calanthe rubens Ridl. Calanthe rubra S.H.Oh, H.J.Suh & C.W.Park Calanthe ruthiae (P.T.Ong & P.O'Byrne) Schuit. Calanthe ruttenii J.J.Sm. Calanthe saccata J.J.Sm. Calanthe sacculata Schltr. Calanthe salaccensis J.J.Sm. Calanthe sandsii P.J.Cribb Calanthe scaposa Z.H.Tsi & K.Y.Lang Calanthe secunda P.J.Cribb Calanthe seranica J.J.Sm. Calanthe siargaoensis M.Leon, Naive & Cootes Calanthe sieboldopsis B.Y.Yang & Bo Li Calanthe simplex Seidenf. Calanthe simulans (Rolfe) M.W.Chase, Christenh. & Schuit. Calanthe sinica Z.H.Tsi Calanthe solomonensis P.J.Cribb & D.A.Clayton Calanthe spathoglottoides Schltr. Calanthe speciosa (Blume) Lindl. Calanthe steinhardtiana (Senghas) M.W.Chase, Christenh. & Schuit. Calanthe stella P.J.Cribb Calanthe stenocentron (Schltr.) M.W.Chase, Christenh. & Schuit. Calanthe striata R.Br. ex Spreng. Calanthe subtriloba (Ames & C.Schweinf.) M.W.Chase, Christenh. & Schuit. Calanthe succedanea Gagnep. Calanthe sylvatica (Thouars) Lindl. Calanthe taenioides J.J.Sm. Calanthe tahitensis Nadeaud Calanthe taibaishanensis M.Guo, J.W.Zhai & L.J.Chen Calanthe takeoi Hayata Calanthe takeuchii Ormerod & P.J.Cribb Calanthe tankervilleae (Banks) M.W.Chase, Christenh. & Schuit. Calanthe tenuis Ames & C.Schweinf. Calanthe testacea M.W.Chase, Christenh. & Schuit. Calanthe tetragona (Thoars) M.W.Chase, Christenh. & Schuit. Calanthe tonkinensis (Aver.) M.W.Chase, Christenh. & Schuit. Calanthe torricellensis Schltr. in K.M.Schumann & C.A.G.Lauterbach Calanthe transiens J.J.Sm. Calanthe tricarinata Lindl. Calanthe trichoneura (Schltr.) M.W.Chase, Christenh. & Schuit. Calanthe trifida Tang & F.T.Wang Calanthe triplicata (Willemet) Ames Calanthe trulliformis King & Pantl. Calanthe truncata J.J.Sm. Calanthe truncicola Schltr. Calanthe tsiana Y.Q.Chen, J.W.Zhai & S.R.Lan Calanthe tsoongiana Tang & F.T.Wang Calanthe tuberculosa (Thoars) M.W.Chase, Christenh. & Schuit. Calanthe uncata Lindl. Calanthe undulata J.J.Sm. Calanthe unifolia Ridl. Calanthe velutina Ridl. Calanthe ventilabrum Rchb.f. in B.Seemann Calanthe versteegii J.J.Sm. Calanthe vestita Wall. ex Lindl. Calanthe villosa J.J.Sm. Calanthe villosagastris (Thoars) M.W.Chase, Christenh. & Schuit. Calanthe wallichii (Lindl.) M.W.Chase, Christenh. & Schuit. Calanthe wenshanensis J.W.Zhai, L.J.Chen & Z.J.Liu Calanthe whistleri P.J.Cribb & D.A.Clayton Calanthe whiteana King & Pantl. Calanthe womersleyi P.J.Cribb & Ormerod Calanthe woodfordii (Hook.) M.W.Chase, Christenh. & Schuit.