Monographs Details: Pleurothallis
Authority: Schweinfurth, Charles. 1967. Orchidaceae of the Guayana Highland. Mem. New York Bot. Gard. 14: 69-214.
Family:Orchidaceae
Scientific Name:Pleurothallis
Description:Distribution and Ecology - BRAZIL. Amazonas: Taracua, Alto Rio Negro, flower yellow, blooming in February, G. Hiibner 166 (flower poor). VENEZUELA. Bolivar: Auydn-tepui, cumbre de la parte norte de la seccion sur (divisi6n occidental del cerro): suelo arenisco entre "Drizzly Camp" y "Second Wall," 1660-1800 m alt., among rocks and on tree branches at the "Second Wall," leaves dull green above and winepurple beneath, 8 mm wide. May 11, 1964, J. A. Steyermark 93727 (this collection has no good flowers and is referable either to Pleurothallis or Octomeria); same locality, cumbre de la parte norte de la seccion sur (division occidental del cerro) : a lo largo del Rio Churún al piede "Second Wall" de arenisca, 6-7 km hacia el noreste del campamento norte, 1600 m alt., epiphyte on tree, leaves coriaceous, 2 cm wide, dark purple beneath, May 13, 1964, Steyermark 93847 (this sterile collection is referable either to Pleurothallis or to Stelis); same locality, cumbre de la parte sureste del brazo noroeste (division occidental del cerro): faldas sobre piedras igneas, vecindad del "Rio Lomita Camp," 1800 m alt., in moist rich mossy forest of quebrada northwest of Rio Lomita Camp, epiphyte on tree, leaves ascending, olive green. May 10, 1964, Steyermark 93636 (plant sterile; aff. P. vittata Lindl.) ; same locality, cumbre de la parte norte de la sección sur (división occidental del cerro) : a lo largo del Rio Churiin al piede "Second Wall" de arenisca, 6-10 km hacia el noreste del campamento norte, 1600 m alt., epiphyte on tree, leaves rich green above and paler beneath. May 13, 1964, Steyermark 93849 (plant sterile) ; same locality, cumbre de la parte norte de la sección sur (división occidental del cerro): a lo largo del Rio Churún, vecindad del campamento sur, 1690 m alt., in riverine forest, epiphyte 1.5 m up on tree trunk, leaves coriaceous, rich green above and pale green beneath, 2 cm wide. May 21, 1964, Steyermark 93237 (plant sterile; aff. P. velaticaulis Reichb. f.); same locality, cumbre de la parte sureste del brazo noroeste (division occidental del cerro): noroeste del "Drizzly Camp," vecindad de afluente del Rio Churiin, oeste del Salto Churún, en bosque hiimedo, 1850 m alt., along large stream, epiphyte on tree branch 2 m up, leaves dull green above and deep magenta-purple beneath, 10-12 mm wide. May 5, 1964, Steyermark 93462 (this plant is in fruit; aff. P. velaticaulis Reichb. f.); Cerro Guaiquinima, Rio Pardgua, 1600-1700 m alt., "North Valley,'' infrequent epiphyte in woodland along watercourse, January 10-12, 1952, B. Maguire 33082 (this collection has imperfect flowers on mature ovaries, but it appears to be nearly allied to the Central American P. Johnsonii Ames) ; Chimantd Massif, northwestern part of Abacapa-tepui, 1210-1600 m alt., in wet mossy forest with sandstone boulders, between Camp 3 and main line of sandstone bluffs, epiphyte on tree trunk, leaves subcoriaceous, rich green above and paler beneath, flower lavender and green, April 17, 1953, J. A. Steyermark 75082; Chimantd Massif, above southeast-facing upper shoulder on slope leading to summit of Apacara-tepui, 2200-2300 m alt., epiphyte on Magnolia in upper mixed Clusia-Magnolia forest, leaves erect, coriaceous, deep green above and paler beneath, suffused with dull magenta, June 20, 1953, Steyermark 75839 (this collection has only mature racemes, but it appears to be closely allied to P. elegans Lindl.) ; Chimantd Massif, Agparaman-tepui, southeast-facing forested slopes below escarpment, 1880-1955 m alt., terrestrial or on tree branches, locally frequent, February 26, 1955, J. A. Steyermark & J. J. Wurdack 1165 (this collection is sterile, but it suggests P. stenocardium Schltr.); Ptari-tepui, 2410-2450 m alt., along base of east-facing high sandstone bluffs, terrestrial or on rocky places, Steyermark 59932 (fruit); Ptari-tepui, Sororopdn-tepui, 1656-1980 m alt., on wooded ridge between quebrada and waterfall (Salto de Iwaracarii-merii), creeping on trunk, Steyermark 60195 (this collection is in fruit, but it closely resembles the West Indian P. Wilsonii Lindl.) ; Rio Carrao (Orchid Island), about 490 m alt., in warm forest, G. C. K. Dunsterville 751 (the status of this collection is in doubt, but its nearest affinity is to Pleurothallis). Amazonas: Mt. Duida, Laterite Valley, Savanna Hills, about 1350 m alt., G. H. H. Tate 764 (sterile); Mt. Duida, Savanna Hills, 1350 m alt., epiphytic in woods, Tate 823 (only one imperfect flower was found, but the plant suggests P. hamosa Barb. Rodr.); same location, Camp Woods, about 1350 m alt., Tate 848, 1051 (sterile).

Discussion:

(flowers absent or imperfect).

Distribution:Brazil South America| Venezuela South America|