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{{Taxobox
| color = lightgreen
| name = ''Trichocentrum''
| image = Trichocentrum-haematochilum.jpg
| image_width = 250px
| image_caption = ''Trichocentrum haematochilum''
| regnum = [[Plant]]ae
| divisio = [[Flowering plant|Magnoliophyta]]
| classis = [[Liliopsida]]
| ordo = [[Asparagales]]
| familia = [[Orchidaceae]]
| subfamilia = [[Epidendroideae]]
| tribus = Maxillariinae
| subtribus = Oncidiinae
| alliance = Trichocentrum
| genus = '''''Trichocentrum'''''
| genus_authority = Poepp. & [[Stephan Ladislaus Endlicher|Endl.]] 1836
| subdivision_ranks = [[Species]]
| subdivision =
See text.
}}
'''''Trichocentrum''''' is a small [[genus]] in the orchid family ([[Orchidaceae]]) with 65 species, many of which have been recently discovered or renamed (M.W.Chase & N.H.Williams, ''Lindleyana'' 16, 2001).
These [[epiphyte|epiphytic]] species are distributed in damp forests from [[Mexico]] to [[South America]], but mostly in [[Venezuela]], [[Colombia]], [[Ecuador]] and [[Peru]]. They are considered by some to be among the most beautiful orchids on earth.
The [[pseudobulb]]s are reduced. The obtuse, fleshy [[Leaf|leaves]] are 9 cm long. They are broadly elliptic to ovate-lanceolate.
The large, showy [[flower]]s grow basally on a short [[peduncle]] in a single-flowered to few-flowered [[raceme]]. They are white, or white covered with maroon dots. The [[petal]]s and [[sepal]]s are similar.
The long [[labellum|lip]] carries a short [[spur]]. This feature distinguishes the genus from other [[Oncidiinae]], in which the spur is an extension of the [[column (botany)|column]]. The short column has a pair of apical wings on the [[Carpel|stigma]]. The [[anther]] often bears minute [[papilla]]e. There are two waxy [[pollinium|pollinia]], connected to elongate [[stipe (botany)|stipe]]s.
Culture of members of this genus is highly variable, ranging from the drought-tolerant and easy-to-grow ''Trichocentrum tigrinum'' to other, smaller species.
''Trichocentrum'' species in cultivation are subject to rot unless provided with conditions similar to those they experience in the wild. Extensive research into the ecological profiles of individual species may be required to achieve success cultivating them. Many species from Central America apparently endure a prolonged drought for at least part of the year, and have developed succulent leaves to deal with these conditions. Plants may shrivel quite severely without long-lasting injury.
Hybridisation of ''Trichocentrum'' with ''Oncidium'' has resulted in the hybrid genus Trichocidium.
There is disagreement as to the taxonomic status of some species that have recently been moved from ''Oncidium'' to ''Trichocentrum''. Morphological characteristics of "typical" trichocentrums, such as being relatively small and squat with a short, few-to-several flowered inflorescence, contrasts sharply with the larger, heavier oncidiums with long, "mule-ear" leaves and showy, branched inflorescences with many flowers, or the "rat-tail" species with [[terete]] leaves. While [[molecular phylogeny]] has caused Williams et al. (2001) to substantially reclassify a number of species, it is uncertain whether this new scheme will be widely adopted.
==Species==
*''[[Trichocentrum aguirrei]]'' (Colombia).
*''[[Trichocentrum albococcineum]]'' : White-scarlet Trichocentrum (N. Brazil to Peru).
*''[[Trichocentrum ascendens]]'' (Mexico to W. South America).
*''[[Trichocentrum aurisasinorum]]'' (C. America).
*''[[Trichocentrum bicallosum]]'' (Mexico- Oaxaca, Chiapas to C. America).
*''[[Trichocentrum brachyceras]]'' (Colombia).
*''[[Trichocentrum brevicalcaratum]]'' (Peru).
[[Image:Trichocentrum-microchilum.jpg|thumb|right|250px|''Trichocentrum microchilum'']]
*''[[Trichocentrum caloceras]]'' (Costa Rica).
*''[[Trichocentrum candidum]]'' : White Trichocentrum (Mexico - Veracruz to Chiapas to C. America).
*''[[Trichocentrum capistratum]]'' : Halter Trichocentrum (Costa Rica to Venezuela).
*''[[Trichocentrum carthagenense]]'' (Caribbean, Mexico to N. Brazil)
*''[[Trichocentrum cavendishianum]]'' (Mexico to C. America).
*''[[Trichocentrum cebolleta]]'' (S. Caribbean, Mexico to NE. Argentina)
*''[[Trichocentrum costaricense]]'' (Costa Rica).
*''[[Trichocentrum cymbiglossum]]'' (Costa Rica).
*''[[Trichocentrum dianthum]]'' (Costa Rica).
*''[[Trichocentrum estrellense]]'' (Costa Rica).
*''[[Trichocentrum flavovirens]]'' (SW. Mexico).
*''[[Trichocentrum fuscum]]'' : Dark Trichocentrum (S. Trop. America).
*''[[Trichocentrum haematochilum]]'' (Trinidad).
*''[[Trichocentrum hartii]]'' (Venezuela).
[[Image:Trichocentrum-splendidum.jpg|thumb|right|250px|''Trichocentrum splendidum'']]
*''[[Trichocentrum hoegei]]'' (Mexico - Veracruz, Guerrero, Oaxaca).
*''[[Trichocentrum ionopthalmum]]'' (N. Brazil).
*''[[Trichocentrum johnii]]'' (Mexico).
*''[[Trichocentrum jonesianum]]'' (Bolivia and Brazil to NE. Argentina).
*''[[Trichocentrum lanceanum]]'' (Trinidad to S. Trop. America).
*''[[Trichocentrum leeanum]]'' (Colombia).
*''[[Trichocentrum lindenii]]'' (Mexico to Guatemala).
*''[[Trichocentrum longicalcaratum]]'' Rolfe
*''[[Trichocentrum lowii]]'' (Guatemala).
*''[[Trichocentrum luridum]]'' (Mexico to N. South America).
*''[[Trichocentrum margalegfii]]'' (SW. Mexico).
*''[[Trichocentrum mattogrossense]]'' (Brazil - Mato Grosso).
*''[[Trichocentrum microchilum]]'' (Mexico - Chiapas to El Salvador).
*''[[Trichocentrum morenoi]]'' (Peru to Bolivia).
[[Image:Trichocentrum-tigrinum.jpg|thumb|right|250px|Tiger-like Trichocentrum <br />''Trichocentrum tigrinum'']]
*''[[Trichocentrum nanum]]'' (S. Trop. America).
*''[[Trichocentrum neudeckeri]]'' (Bolivia).
*''[[Trichocentrum nudum]]'' (Panama to Venezuela).
*''[[Trichocentrum obcordilabium]]'' (Ecuador).
*''[[Trichocentrum oestlundianum]]'' (SW. Mexico).
*''[[Trichocentrum orthoplectron]]'' (Colombia to N. Brazil).
*''[[Trichocentrum ostenianum]]'' (Paraguay).
*''[[Trichocentrum panduratum]]'' (N. Peru.
*''[[Trichocentrum pfavii]]'' : Pfau's Trichocentrum (C. America.
**''Trichocentrum pfavii'' subsp. ''dotae'' (Costa Rica).
**''Trichocentrum pfavii'' subsp. ''pfavii'' (C. America).
*''[[Trichocentrum pinelii]]'' (Brazil - Rio de Janeiro).
*''[[Trichocentrum pohlianum]]'' (SE. Brazil)
*''[[Trichocentrum pongratzianum]]'' (Peru).
*''[[Trichocentrum popowianum]]'' (Ecuador).
*''[[Trichocentrum porphyrio]]'' (N. Brazil).
*''[[Trichocentrum pulchrum]]'' : Long-spurred Trichocentrum, Beautiful Trichocentrum (S. Trop. America). '''[[type species]]'''
*''[[Trichocentrum pumilum]]'' (Brazil to NE. Argentina).
*''[[Trichocentrum purpureum]]'' (Guyana).
*''[[Trichocentrum recurvum]]'' (Guiana, Suriname).
*''[[Trichocentrum splendidum]]'' (Guatemala).
*''[[Trichocentrum sprucei]]'' (Suriname to Brazil).
*''[[Trichocentrum stacyi]]'' (Bolivia).
*''[[Trichocentrum stipitatum]]'' (C. America).
*''[[Trichocentrum stramineum]]'' (Mexico - Veracruz).
*''[[Trichocentrum teaguei]]'' (Bolivia).
*''[[Trichocentrum tenuiflorum]]'' (NE. Brazil).
*''[[Trichocentrum teres]]'' (Costa Rica to Panama).
*''[[Trichocentrum tigrinum]]'' : Tiger-like Trichocentrum (C. America to Peru).
*''[[Trichocentrum undulatum]]'' (S. Florida to N. Brazil).
*''[[Trichocentrum viridulum]]'' (Colombia).
*''[[Trichocentrum wagneri]]'' (Brazil).
*''[[Trichocentrum wittii]]'' (Bolivia).
==Natural hybrid==
*''Trichocentrum × marvraganii'' (T. jonesianum × T. straceyi) (Bolivia)
==References==
* Williams, N. H., Chase, M. W., Fulcher, T., and Whitten, W. M. 2001. Molecular systematics of the Oncidiinae based on evidence from four DNA sequence regions: expanded circumscriptions of Cyrtochilum, Erycina, Otoglossum, and Trichocentrum and a new genus (Orchidaceae). Lindleyana 16(2): 113-139.
* Ackerman, J. D. and Chase, M. W. 2001. Notes on the Caribbean orchid flora, 4. More combinations in Trichocentrum and Cyrtochilum. Lindleyana 16(4): 225.
* Chase, M. W. and Williams, N. H. 2001. Additional transfers to Trichocentrum Poepp. & Endl. and Otoglossum Garay & Dunst. (Orchidaceae: Oncidiinae). Lindleyana 16(3): 218-219.
* Sandoval-Zapotitla, E. and Terrazas, T. 2001. Leaf anatomy of 16 taxa of the Trichocentrum clade (Orchidaceae: Oncidiinae). Lindleyana 16: 81-93.
[[Category:Orchid genera]]