Heterotaxis: Difference between revisions

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| image = Heterotaxis crassifolia.jpg
| image = Heterotaxis crassifolia.jpg
| image_caption = ''Heterotaxis crassifolia''
| image_caption = ''Heterotaxis sessilis''
| domain = [[Eukaryota]]
| domain = [[Eukaryota]]
| regnum = [[Plantae]]
| regnum = [[Plantae]]
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'''''Heterotaxis''''' is a genus of [[orchid]]s formed by a group of circa fourteen neotropical species which previously were considered part of genus ''[[Maxillaria]]''. They are large [[epiphytic]] plants of small flowers.
'''''Heterotaxis''''' is a genus of [[orchid]]s formed by a group of circa fourteen neotropical species which previously were considered part of genus ''[[Maxillaria]]''. They are strong [[epiphytic]] plants with shiny dark green [[leave]]s which make a showy display making a very good first impression but end disappointing because of their small [[flower]]s, usually yellow, which, because of their short [[inflorescence]]s, hide between the foliage and can hardly be seen. Although the species that belong to this genus are easy to identify, because they vary a lot and are much similar to each other, to diferentiate them is hard, with very few exceptions.
 
== Distribution==
The range of distribution of ''Heretotaxis'' is wide, particularly because of the type species, ''H. sessilis'', which can be found from South [[Florida]], [[Caribbean]] and [[Mexico]], spread through all [[Central America]] countries to tropical America, reaching [[Bolivia]] and South [[Brazil]].
 
All species are mostly epiphytic, despite some hardly ever can be seen living as [[litophyte]]s on shady and humid cliffs. The species of ''Heterotaxis'' hardly ever are found living under full [[sunlight]], being more common under the shelter and shade of trees. They are strong plants that can adapt to diferent environment conditions, since very wet [[forest]]s of Florida and [[Amazon]], to cloud mountain forests in the [[Andes]] and along [[Serra do Mar]] mountains in Brazil, and even in dry jungles of [[highland]]s of Central Brazil. Some species, like ''Heterotaxis equitans'' can be found also living at the edges of the jungles were the get more light than most of other species of this genus.
 
==Description==
''Heterotaxis'' are comparatively large and robust plants, usually of [[sympodial growth]], with unifoliate lateraly compressed [[pseudobulb]]s, protected by several foliar [[stealth]]s of almost always glossy foliage; or they can also lack pseudobulbs and have [[distical]] leaves, then growing simulating [[monopodial growth]]. All species have small thick flowers, which frequently do not open interely, ordinaryly yellowish, but also orange or white, sometimes with purple-bluish, lilac or brown-red spots. A thickening on the center of the lip is also common, sometimes it is covered by waxy [[trichome]]s that atract [[pollinator]]s. Their [[column]] is very short. As all species once subordinated to ''[[Maxillaria]]'' the inflorescences are lateral and bear just one flower, and here are long, short or very short, in small numbers, ordinarily blooming more than once a year.  


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[[Imagem:Heterotaxis equitans 01.jpg|thumb|right|226px|''Heterotaxis equitans''<br/><br/> Espécie facilmente identificável tanto pela planta como pelas flores.]]
[[Imagem:Heterotaxis equitans 01.jpg|thumb|right|226px|''Heterotaxis equitans''<br/><br/> Espécie facilmente identificável tanto pela planta como pelas flores.]]
*América do Norte: [[Estados Unidos]] e [[México]].
*América Central: [[Belize]], [[Costa Rica]], [[El Salvador]], [[Guatemala]], [[Honduras]], [[Nicarágua]] e [[Panamá]].
*[[Caribe]]: [[Trinidad e Tobago]], [[Cuba]], [[República Dominicana]], [[Haiti]] e [[Jamaica]].
*[[América do Sul]]: [[Brasil]] ([[Rondônia]], [[Amazonas]], [[Pará]], [[Amapá]], [[Roraima]], [[Goiás]], [[Tocantins]], [[Mato Grosso]], [[Mato Grosso do Sul]], [[Paraíba]], [[Santa Catarina]]), [[Guianas]], [[Suriname]], [[Venezuela]], [[Colômbia]], [[Equador]], [[Peru]] e [[Bolívia]].
Geralmente ocorrem em matas secas e moderadamente sombreadas.


==Histórico==
==Histórico==
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Finalmente, [[F.Barros|Fábio de Barros]] publicou um trabalho em 2002 reestabelecendo o gênero antigo gênero ''Heterotaxis'', o primeiro  proposto por Lindley. Tanto a [[filogenia]] moderna como todas as descrições recentes reforçam a validade deste gênero. Até hoje todas estas espécies são conhecidas somente pelos seus sinônimos ''Marsupiaria'' e ''Maxillaria''.
Finalmente, [[F.Barros|Fábio de Barros]] publicou um trabalho em 2002 reestabelecendo o gênero antigo gênero ''Heterotaxis'', o primeiro  proposto por Lindley. Tanto a [[filogenia]] moderna como todas as descrições recentes reforçam a validade deste gênero. Até hoje todas estas espécies são conhecidas somente pelos seus sinônimos ''Marsupiaria'' e ''Maxillaria''.
==Morfologia==
São plantas [[epífita]]s comparativamente grandes e robustas, geralmende de crescimento [[simpodial]], com [[pseudobulbo]]s unifoliados lateralmente comprimidos, com folhagens vistosas, quase sempre lustrosas, protegidos por diversas baínhas foliares; ou então sem pseudobulbos, com folhas dísticas e crescimento pseudo-monopodial. Todas apresentam pequenas e espessas flores campanuladas, geralmente amareladas com coluna muito curta e labelo com um amontoado de pilosidades que atrai insetos polinizadores. As [[inflorescência]]s apresentam uma única flor, são laterais, curtas ou longas, em pouca quantidade, em regra mais de uma vez por ano.





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Heterotaxis
Heterotaxis sessilis
Heterotaxis sessilis
Scientific classification
Domain: Eukaryota
Kingdom: Plantae
Division: Magnoliophyta
Class: Liliopsida
Order: Asparagales
Family: Orchidaceae
Subfamily: Epidendroideae
Tribe: Cymbidieae
Subtribe: Maxillariinae
Genus: Heterotaxis
Lindl. 1826
Type species
Heterotaxis crassifolia
Lindl. 1826
Species
  • 14 species, see text
Synonym

Heterotaxis is a genus of orchids formed by a group of circa fourteen neotropical species which previously were considered part of genus Maxillaria. They are strong epiphytic plants with shiny dark green leaves which make a showy display making a very good first impression but end disappointing because of their small flowers, usually yellow, which, because of their short inflorescences, hide between the foliage and can hardly be seen. Although the species that belong to this genus are easy to identify, because they vary a lot and are much similar to each other, to diferentiate them is hard, with very few exceptions.

Distribution

The range of distribution of Heretotaxis is wide, particularly because of the type species, H. sessilis, which can be found from South Florida, Caribbean and Mexico, spread through all Central America countries to tropical America, reaching Bolivia and South Brazil.

All species are mostly epiphytic, despite some hardly ever can be seen living as litophytes on shady and humid cliffs. The species of Heterotaxis hardly ever are found living under full sunlight, being more common under the shelter and shade of trees. They are strong plants that can adapt to diferent environment conditions, since very wet forests of Florida and Amazon, to cloud mountain forests in the Andes and along Serra do Mar mountains in Brazil, and even in dry jungles of highlands of Central Brazil. Some species, like Heterotaxis equitans can be found also living at the edges of the jungles were the get more light than most of other species of this genus.

Description

Heterotaxis are comparatively large and robust plants, usually of sympodial growth, with unifoliate lateraly compressed pseudobulbs, protected by several foliar stealths of almost always glossy foliage; or they can also lack pseudobulbs and have distical leaves, then growing simulating monopodial growth. All species have small thick flowers, which frequently do not open interely, ordinaryly yellowish, but also orange or white, sometimes with purple-bluish, lilac or brown-red spots. A thickening on the center of the lip is also common, sometimes it is covered by waxy trichomes that atract pollinators. Their column is very short. As all species once subordinated to Maxillaria the inflorescences are lateral and bear just one flower, and here are long, short or very short, in small numbers, ordinarily blooming more than once a year.