A new Stelis (Orchidaceae: Pleurothallidinae) from the Western Andes of Colombia

Abstract

Stelis excentrica, a new species endemic to the Cauca slope of the western Andes, municipality of Cali, Valle del Cauca, Colombia, is described and illustrated. It was found in the northern part of the Farallones de Cali National Park, in the vicinity of the protected area “El Danubio” administered by the Cali mayoralty. Stelis excentrica is similar to Stelis gigantissima from Ecuador but differs in the ocher-green flowers (vs. dark purple), the reniform petals (vs. flabellate petals), subquadrate lip with a minute apicule (vs. subcuneate without apicule). Reaching up to 30.6 mm from the apex of the dorsal sepal to the apex of the lateral sepal, Stelis excentrica probably has the largest flowers reported in any member of Stelis subgen. Stelis. Its 60 cm long inflorescence is only rivaled by that of Stelis gigantissima. Ecological notes, in situ photographs, typus illustration, maps, and a composite plate are provided.
 Key Words: biggest flower, Farallones de Cali, Stelis gigantissima, taxonomy