Phymatochilum: Difference between revisions

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==Distribution and habit==
==Distribution and habit==
''Phymatochilum brasiliense'' is a comparatively large sympodial epiphyte species which inhabits high areas of the [[Atlantic Forest]] of [[Rio de Janeiro State|Rio de Janeiro]], [[São Paulo State|São Paulo]], [[Espírito Santo]] and [[Pernambuco]] States of Brazil,<ref name="OB"><span style="font-variant:small-caps">Pabst, Guido & Dungs, Fritz </span>: '''Orchidaceae Brasilienses vol. 2''' p. 195. Brucke-Verlag Kurt Schmersow, Hildesheim, 1978. ISBN 3871050107 </ref> particularly in the warmer areas around [[Serra do Mar]] chain of mountains, where it is somewhat rare. It grows under the shadow of [[tree]]s, however, mostly near the jungles well ventilated clearances where it can get brighter light, between 600 and 1,300 meters of [[altitude]] in dryer areas. It ordinarily grows over the trees where the shade is not intense, on thick branches.<ref><span style="font-variant:small-caps">Baker, Charles O & Baker, Margaret L.</span> (2006), ''Miltonia phymatochila'' in '''Orchid Species Culture''' Oncidium/Odontoglossum Alliance: 345, Timber Press. ISBN 9780881927757 </ref>  
''Phymatochilum brasiliense'' is a comparatively large sympodial epiphyte species which inhabits high areas of the [[Atlantic Forest]] of [[Rio de Janeiro State|Rio de Janeiro]], [[São Paulo State|São Paulo]], [[Espírito Santo]], [[Minas Gerais]] and [[Pernambuco]] States of Brazil,<ref name="OB"><span style="font-variant:small-caps">Pabst, Guido & Dungs, Fritz </span> (1978). '''Orchidaceae Brasilienses vol. 2''' p. 195. Brucke-Verlag Kurt Schmersow, Hildesheim. ISBN 3871050107 </ref> particularly in the warmer areas around [[Serra do Mar]] chain of mountains, where it is somewhat rare. It grows under the shadow of [[tree]]s, however, mostly near the jungles well ventilated clearances where it can get brighter light, between 600 and 1,300 meters of [[altitude]] in dryer areas. It ordinarily grows over the trees where the shade is not intense, on thick branches.<ref><span style="font-variant:small-caps">Baker, Charles O & Baker, Margaret L.</span> (2006). ''Miltonia phymatochila'' in '''Orchid Species Culture''' Oncidium/Odontoglossum Alliance: 345, Timber Press. ISBN 9780881927757 </ref>  


==Description==
==Description==
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The [[petal]]s and [[sepal]]s are white and oblong, the sepals slightly larger than the petals, sometimes with the apexes reflected. The petals are similar to the sepals but slightly narrower at the base. The labellum is strong yellow margined of bright purple; at the base it is fused to the [[Column (botany)|column]] base forming a narrow spur shaped [[nectary]]; it is internally slightly pubescent and has a thick callus that splits in five digitate keels on the disk; the central lobe is partially saccate and has two longer fringes at the apex. The column is white almost cylindrical without any appendages. The [[anther]], contrasting to the flower, is  very bright purple, apical, bearing six [[pollinia]], four small and two large, hold by a [[caudicle]] similar to the ones of ''Leptotes''.<ref name="W"/>
The [[petal]]s and [[sepal]]s are white and oblong, the sepals slightly larger than the petals, sometimes with the apexes reflected. The petals are similar to the sepals but slightly narrower at the base. The labellum is strong yellow margined of bright purple; at the base it is fused to the [[Column (botany)|column]] base forming a narrow spur shaped [[nectary]]; it is internally slightly pubescent and has a thick callus that splits in five digitate keels on the disk; the central lobe is partially saccate and has two longer fringes at the apex. The column is white almost cylindrical without any appendages. The [[anther]], contrasting to the flower, is  very bright purple, apical, bearing six [[pollinia]], four small and two large, hold by a [[caudicle]] similar to the ones of ''Leptotes''.<ref name="W"/>
{{Image|Loefgrenianthus blancheamesiae9.jpg|right|300px|'''''Loefgrenianthus blanche-amesiae'''''<br><small>The pending habit of this species easily separates it from the closest genus ''Leptotes''.</small>}}
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==Taxonomic notes==
==Taxonomic notes==
<!--
For some unknown reason there is a number of original descriptions by [[John Lindley]], of plants received from Loddiges, that record [[Mexico]], instead of Brazil, as the country of origin of the plants. It is not known if this information came from [[Lodd.|Loddiges]], whether they were later confusions at the herbarium or either if it was a mistake on transport records. Some of these mistakes, particularly when occurred with less noticeable plants as ''[[Pabstiella crenata]]'' are still been solved. Some of these descriptions yet have to be cleared. The description of ''Phymatochilum brasiliense'' was one of these mistakes. This species is not recorded in Mexico or [[Central America]] after this early records.<ref name="K"><span style="font-variant:small-caps;">Govaerts, Rafaël ''et al''</span>: '''World Checklist of Orchidaceae'''. The Board of Trustees of the Royal Botanic Gardens, Kew. [http://www.kew.org/wcsp Published on Internet] (Access in March 2009).</ref> Anyway, in 1847, Lindley received two different plants one from Loddiges and another from reverend Clowes, from Liverpool, an orchid enthusiast Lindley homaged when describing ''[[Miltonia clowesii]]'', and the following year he described it under the genus ''Oncidium'' as ''O. phymatochilum''.<ref><span style="font-variant:small-caps;">Lindley, John</span> (1848). ''Oncidium phymatochilum'' in '''Gardeners' Chronicle and Agricultural Gazette 1848''': 139. England.</ref>
{{Image|Loefgrenianthus blancheamesiae9.jpg|right|300px|'''''Loefgrenianthus blanche-amesiae'''''<br><small>The pending habit of this species easily separates it from the closest genus ''Leptotes''.</small>}}
 
The Danish Botanist [[Johan Albert Constantin Loefgren]] lived many years in Brazil where he was studying the [[flora]] of [[Minas Gerais]] State, painting [[watercolor]]s of plants and was a director of [[Rio de Janeiro Botanic Garden]]. In 1896 while looking for new specimens on Serra da Mantiqueira, in Rio de Janeiro, he came across a small plant the did not recognize. At the time the Belgian Botanist [[Célestin Alfred Cogniaux]] was working on the noted [[Flora Brasiliensis]] of [[Carl Friedrich Philipp von Martius]], am encyclopedia that described all plant species of Brazil known at the time. Therefore, trying to establish its identity, Loefgren sent the plant he found to Cogniaux, however, the specimen got lost and was never recovered.  
This species, whose flowers are very similar to the ones of ''Oncidium'' was in fact considered a member of this genus until 2001 when, based on the results of their molecular analysis, it was moved by [[N.H.Williams| Norris Williams]] and [[M.W.Chase|Mark Chase]] to the genus ''Miltonia''. On the transfer publication they claim that, despite the morphologic differences, the relationship is very close and, supposedly, they did not want to propose a new genus to subordinate one species only.<ref><span style="font-variant:small-caps">Williams, Norris H. & Chase, Mark W.</span> (2001). ''Miltonia phymatochila'' in '''Lindleyana 16''': 284.</ref> As this species shows a morphology that is closer to ''Oncidium'' species than to ''Miltonia'', because of its small yellowish flowers and highly branched inflorescence, this result and following transfer was a great surprise to most taxonomists. Therefore, in 2005, [[Eric Christenson]] suggested a new genus and the name ''Phymatochilum brasiliense'' for it.<ref><span style="font-variant:small-caps">Christenson, Eric A.</span> (2005). ''Phymatochilum brasiliense'' in '''Richardiana 5''': 195.</ref> There is no consensus about the name to be generally accepted as yet.
In 1915 the professor [[Oakes Ames]], botanist responsible for the [[herbarium]] of [[Harvard University]], and his wife Blanche were traveling in Brazil and met Loefgren. Together they accidentally found again, on the slopes of Itatiaia mountain, another specimen of the plant which had been lost almost ten years before.<ref><span style="font-variant:small-caps;">Oakes Ames</span>: ''The rediscovery of a lost orchid'' in '''Orchids in retrospect''' (1948)</ref> This time Loefgreen decided to describe the species himself and considering it close to ''Leptotes'' placed it under this genus with the name ''Leptotes blanche-amesiae'' in homage to professor Ames wife.<ref><span style="font-variant:small-caps;">Loefgren, Johan Albert Constantin</span>: ''Novos subsídios para a flora Orchidaceae do Brasil'' in '''Arquivos do Jardim Botânico do Rio de Janeiro Vol.2''': p. 58. Rio de Janeiro, 1918.</ref> In 1827, a later work on the genus ''Leptotes'' by [[Frederico Carlos Hoehne]] led him to conclude that this species, despite being closely related to it, would be better placed in another genus, therefore he proposed the genus ''Loefgrenianthus'', in reference to Loefgren who, besides discovering the species twice, had described it.<ref><span style="font-variant:small-caps;">Hoehne, Frederico Carlos</span>: ''Loefgrenianthus blanche-amesiae'' in '''Boletim do Instituto Brasileiro de Sciencias vol.2: 352. São Paulo, 1927.</ref>


According to [[Cássio van den Berg]], who studied their [[phylogeny]], ''Loefgrenianthus'' is closely related to ''[[Leptotes]]'' and both form a sister clade to another small clade that includes ''[[Pseudolaelia]]'', ''[[Constantia]]'' and ''[[Isabellia]]''. The two clades constitute ''Isabellia'' alliance, which is one of the eight clades of subtribus [[Laeliinae]].<ref><span style="font-variant:small-caps;">Van den Berg, Cássio ''et al''</span>: ''A Phylogenetic analysis of Laellinae based on sequence data from internal transcribed spacers of nuclear ribosomal DNA'' in '''Lindleyana vol.15-2''', pp. 96–114, 2000. [http://www.cassiovandenberg.hpg.ig.com.br/pdfs/vandenbergetal2000.pdf Published on Internet].</ref>  
Molecular analysis shows that ''Phymatochilum'' most closely related genus is ''[[Miltonia]]'' and then ''[[Aspasia]]'', ''[[Brassia]]'' and ''[[Ada]]'', which are the most important genera included in this that is one of the eight clades that form the subtribus [[Oncidiinae]] of tribus [[Cymbidieae]].<ref name="NH"><span style="font-variant:small-caps">Williams NH, Chase MW, Fulcher T, Whitten WM</span> (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)'' in '''Lindleyana 16(2)''': 113-139.</ref>


Em 2001, com base em resultados de análises filogenéticas o gênero recebeu o acréscimo de mais uma espécie, previamente classificada como Oncidium phymatochilum , a ser classificada como Miltonia phymatochila. Espécie de morfologia por demais divergente das outras Miltonia , esta proposta não encontrou eco entre muitos taxonomistas. Em 2005 Eric Christenson propôs um novo gênero uniespecífico para ela, que seria então denominada Phymatochilum brasiliense.
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==References==
==References==
{{reflist|2}}
{{reflist|2}}

Revision as of 10:01, 19 March 2009

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Phymatochilum
Phymatochilum brasiliense.jpg
Scientific classification
Domain: Eukaryota
Kingdom: Plantae
Division: Magnoliophyta
Class: Liliopsida
Order: Asparagales
Family: Orchidaceae
Subfamily: Epidendroideae
Tribe: Cymbidieae
Subtribe: Oncidiinae
Genus: Phymatochilum
Christenson 2005
Type species
Oncidium phymatochilum
Lindl. 1848
Species
Synonyms
  • None

Phymatochilum is an orchid genus formed by only one species, Phymatochilum brasiliense, inhabitant of Serra do Mar mountains in Brazilian southeast and northeast, which vegetatively resembles Oncidium species, however, is more closely related to the genus Miltonia.

Distribution and habit

Phymatochilum brasiliense is a comparatively large sympodial epiphyte species which inhabits high areas of the Atlantic Forest of Rio de Janeiro, São Paulo, Espírito Santo, Minas Gerais and Pernambuco States of Brazil,[1] particularly in the warmer areas around Serra do Mar chain of mountains, where it is somewhat rare. It grows under the shadow of trees, however, mostly near the jungles well ventilated clearances where it can get brighter light, between 600 and 1,300 meters of altitude in dryer areas. It ordinarily grows over the trees where the shade is not intense, on thick branches.[2]

Description

Measures (mm)
Structure Lenght Width
Rhizome 15 15
Leaf 500 100
Pseudobulb 100 70
Inflorescence 1800 -
Flower 50 25
Sepal 35 3
Petal 25 3
Labellum 18 12

Phymatochilum brasiliense blooms between from the end of summer to middle autumn and its sweet fragrant flowers last for about two weeks. There is no reference about their pollinators.

Taxonomic notes

For some unknown reason there is a number of original descriptions by John Lindley, of plants received from Loddiges, that record Mexico, instead of Brazil, as the country of origin of the plants. It is not known if this information came from Loddiges, whether they were later confusions at the herbarium or either if it was a mistake on transport records. Some of these mistakes, particularly when occurred with less noticeable plants as Pabstiella crenata are still been solved. Some of these descriptions yet have to be cleared. The description of Phymatochilum brasiliense was one of these mistakes. This species is not recorded in Mexico or Central America after this early records.[3] Anyway, in 1847, Lindley received two different plants one from Loddiges and another from reverend Clowes, from Liverpool, an orchid enthusiast Lindley homaged when describing Miltonia clowesii, and the following year he described it under the genus Oncidium as O. phymatochilum.[4]

This species, whose flowers are very similar to the ones of Oncidium was in fact considered a member of this genus until 2001 when, based on the results of their molecular analysis, it was moved by Norris Williams and Mark Chase to the genus Miltonia. On the transfer publication they claim that, despite the morphologic differences, the relationship is very close and, supposedly, they did not want to propose a new genus to subordinate one species only.[5] As this species shows a morphology that is closer to Oncidium species than to Miltonia, because of its small yellowish flowers and highly branched inflorescence, this result and following transfer was a great surprise to most taxonomists. Therefore, in 2005, Eric Christenson suggested a new genus and the name Phymatochilum brasiliense for it.[6] There is no consensus about the name to be generally accepted as yet.

Molecular analysis shows that Phymatochilum most closely related genus is Miltonia and then Aspasia, Brassia and Ada, which are the most important genera included in this that is one of the eight clades that form the subtribus Oncidiinae of tribus Cymbidieae.[7]

References

  1. Pabst, Guido & Dungs, Fritz (1978). Orchidaceae Brasilienses vol. 2 p. 195. Brucke-Verlag Kurt Schmersow, Hildesheim. ISBN 3871050107
  2. Baker, Charles O & Baker, Margaret L. (2006). Miltonia phymatochila in Orchid Species Culture Oncidium/Odontoglossum Alliance: 345, Timber Press. ISBN 9780881927757
  3. Govaerts, Rafaël et al: World Checklist of Orchidaceae. The Board of Trustees of the Royal Botanic Gardens, Kew. Published on Internet (Access in March 2009).
  4. Lindley, John (1848). Oncidium phymatochilum in Gardeners' Chronicle and Agricultural Gazette 1848: 139. England.
  5. Williams, Norris H. & Chase, Mark W. (2001). Miltonia phymatochila in Lindleyana 16: 284.
  6. Christenson, Eric A. (2005). Phymatochilum brasiliense in Richardiana 5: 195.
  7. Williams NH, Chase MW, Fulcher T, Whitten WM (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) in Lindleyana 16(2): 113-139.