Oncidium pardothyrsus Rchb. f. & Warsz. 1857 SECTION Planilabra Photo courtesy of Jay Pfahl

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Common Name The Dark Bunch Oncidium
Flower Size 3/8" [1 cm]
Found in Peru and Ecuador on the western slopes of the Andes as an ascending, small sized, hot to warm growing epiphyte that occurs at elevatons of 500 to 1500 meters in damp forests with a distinct dry season in the spring through fall, with ovate-elliptic, complanate, lightly sulcate pseudobulbs subtended by a pair of conduplicate leaf-bearing bracts and 2, apical, lorate, long-attenuate to the conduplicate base, long tapered to the acute apex of the leaf and blooms in the winter on a basal, to 6' 10" [to 205 cm] long, erect to arcuate, paniculate inflorescence, arising on a mature pseudobulb with 2 to 8 flowers per each branch.
Many sources say this is a synonym of Onc planilabre Lindley 1851, but I have left it as a separate species until the DNA evidence is available.
Synonyms Oncidium subobscurum Kraenzl. 1922
References W3 Tropicos, Kew Monocot list , IPNI ; Icones Orchidacearum Peruviarum Plate 339 Bennett & Christenson 1995 drawing fide; Native Ecuadorian Orchids Vol 4 Dodson 2003 photo fide; Orchid Species Culture: Oncidium, Bakers 2006; Oncidium Vol 3 Koniger as O planilabre; The Pictoral Encyclopedia of Oncidium Zelenko 2002; Orchid Species of Peru Zelenko Bermudez 2009 photo fide; Orquideas del Peru Freuler 2010 photo fide
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