Oncidium concolor Hook. 1841 SECTION Concoloria Photos by © Stefan Paeffgen
Photo by © Sylvia and Cedrics Orchid Page
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Common Name The Single-Colored Oncidium
Flower Size about 2" [about 5 cm]
found in Minas Gerais, Rio de Janiero and Sao Paulo states of Brazil and northern Argentina in areas frequented by short frosts in montane forests at elevations of 300 to 1500 meters as a small sized, cool to cold growing epiphyte with clustered, narrowly oblong or ovoid-oblong, sulcate in time pseudobulbs carrying 2 apical, rigid, erect spreading, lanceolate-ligulate, acute leaves that blooms in the spring and summer with an arcuate to pendant, 12" [30 cm] long, slightly fractiflex raceme with apressed, concave, pale green bracts that has loosely a few to many [4 to 12 ], spiced apple pie scented flowers.
Potting or mounting with treefern works well if given warm to cool temperatures, moderately bright light and good air movement.
This species and Oncidium ottonis are similar and often considered the same but differ in O concolor having the 2 lamellae of the callus are of unequal height from the top to the bottom and other lip variants, but the easiest way to distinguish the two is that O ottonis always has brown spoltches on the dorsal side of the sepals and O concolor is consistently yellow to yellow green with no spotting.
Synonyms Brasilidium concolor (Hook.) F.Barros & V.T.Rodrigues 2010; Carenidium concolor (Hook.) Baptista 2006; Concocidium concolor (Hook.) Romowicz & Szlach. 2006; Cyrtochilum citrinum Hooker 1849; Gomesa concolor (Hook.) M.W.Chase & N.H.Williams 2009; Oncidium normani hort. ex Pritz. 1840; Oncidium unguiculatum Klotsch 1846
References W3 Tropicos, Kew Monocot list , IPNI ; Die Orchideen Schlechter 1915; Atlas des Orchidees Cultivees Constantin 1920 drawing fide; Das Pflanzanreich Regni Vegetabilis Conspectus Odontoglossum/Oncidium Kranzlin 1922 drawing ok; AOS Bulletin Vol 26 No 10 1957 drawing fide; Encyclopedia of Cultivated Orchids Hawkes 1965; Flora de Venezuela Foldats Volumen XV Part 5 1970; Orchidaceae Brasilenses Band 2 Pabst & Dungs 1977 drawing fide; AOS Bulletin Vol 56 No 6 1987 Postage Stamp fide; The Manual Of Cultivated Orchid Species Bechtel, Cribb & Launert 1992 photo fide; Orchids of the High Mountain Atlantic Rainforest in SE Brazil Warren & Miller 1994; Orchid Digest Vol 61 #3 1997 photo fide; Rudolf Schlechter Die Orchideen Band 1C lieferung 33 - 36 2057 - 2308 Brieger 1997 drawing ok/photo fide; Orchid Digest Vol 63 #1 1999 photo fide; Australian Orchid Review Vol 66 No 2 2001 photo; AOS Bulletin Vol 71 No 7 2002 photo fide; The Pictoral Encyclopedia of Oncidium Zelenko 2002 AOS Bulletin Vol 74 No 11 2005 photo fide; Oncidium Vol 2 Koniger 2005 drawing/photo fide; 100 Orquideas Argentinas Freuler 2005 photo fide; Orchid Species Culture: Oncidium, Bakers 2006; Orchids of Brazil Vol 1 Oncidinae Baptista, Harding & Neto 2011 as Brasilidium concolor photo fide; Orchid Digest Vol 82 #3 2016 as Gomesa concolor; AOS Bulletin Vol 85 #2 2016 photo fide; AOS Bulletin Vol 86 # 3 2017 drawing fide
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