Pleurothallis costabilis Luer & R.Vásquez 1991 SUBGENUS Acianthera [Scheidw.] Luer 1986
TYPE Drawing by Carl Luer and The Swiss Orchid Foundation at the Jany Renz Herbaria Website
EARLY 
Common Name The Rib-Like Pleurothallis [refers to the habit of the plant]
Flower Size .2" [5 mm]
Found in La Paz department of Bolivia at elevations around 1500 meters as a small sized, cool growing, repent epiphyte with erect, relatively stout ramicauls enveloped by 4 tubular sheaths and carrying a single, apical, erect, thick, terete, acute, sessile base leaf that blooms in the early summer on a short, arising through and concealed by a spathe, peduncle .08 to .12" [2 to 3 mm] long, in a fascile of successively single, few flowered inflorescence with thin, shorter to as long as the ovary floral bracts.
"Characterized by the stout, creeping rhizome with tall, ascending ramicauls that give the plant an appearance of bearing ribs. The leaves are narrowly terete and nearly as long as the ramicauls. The short, peduculate flowers are produced singly and successively in a fascile at the apex of the ramicaul. The sepals are fleshy, concave and glabrous. The lip is thick and oblong with an erose apex and a pair of uncinate lobes below the middle." Luer 2004
Synonyms Acianthera costabilis (Luer & R.Vásquez) Luer 2004
References W3 Tropicos, Kew Monocot list , IPNI ;
* Lindleyana 6: 94 Luer & Vasquez 1991 Drawing fide;
Orchids of Bolivia Vol 1 Pleurothallidinae Vasquez & Ibisch 2000;
Icones Pleurothallidinarum Vol XXVI Pleurothallis subgenus Acianthera and Three Allied subgenera, A Second Century of new Species of Stelis of Ecuador, Epibator, Ophidion and Zootrophion Luer 2004 as Acianthera costabilis drawing fide;
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