Epidendrum riverae Hagsater 2019 GROUP Nanodes

Plant and Flower

TYPE LCDP by C. C. Rivera & A. Cisneros & A. Cisneros/Photo by C. C. Rivera and The AMO Herbario Website

Common Name Rivera's Epidendrum [In honor of Cristian Camilo Rivera Jiménez, (1990-) of Tolima, Colombia, a Forestry Engineer, who specializes in trees and works on conservation projects in Colombia, and who collected and photographed the type specimen in its habitat.]

Flower Size .4" [1 cm]

Found in Antioquia department of Colombia in the lowlands of the Atlantic basin south of the Golfo de Urabá; epiphytic on Machaerium aff. capote Triana ex Dugand, at elevations around 20 meters as a mini-miniature sized, hot growing epiphyte with a rhizome creeping along the substrate, stem, totally covered by foliar sheaths, new stem produced near the middle of the previous stem, below the leaves and carrying 6 to 8, distributed throughout the stem, the middle leaves larger, progressively smaller towards the apex, fleshy succulent, dark green, non-articulate with the sheath; bladeconduplicate at the base so that the stem appears laterally compressed, ovate-elliptic, apex unequally bilobed, apical margin minutely erose-crenate leaves that blooms in the spring on a terminal, without a spathe single flowered, sessile, inflorescence flowering only once with similar to the leaves but smaller, translucent, conduplicate, with a prominent dorsal keel, margin minutely erose, sometimes accompanied by a very small bracts to 3 x 2 mm, conduplicate, sub-orbicular floral bracts and carrying a sessile, copper green due to small purple dotted flowers with the base of clinandrium-hood and anther pale purple; apparently without fragrance.

"Epidendrum riverae belongs to the GROUP Nanodes, characterized by the caespitose to creeping, sympodial plants, the short stems completely covered by the base of the non-articulate, fleshy, imbricating leaves; and having sessile, few-flowered inflorescences. The new species is recognized by the low, creeping habit, no more than .8" [2 cm] tall, single flowered, sepals .4" [10 mm] long, column .24" [6 mm] long, sepals oblong, apex somewhat rounded, acute, clinandrium-hood, bifid, margin fimbriate, anther long ovoid ending in a long, fimbriate appendage. Epidendrum longirepens from the Amazon basin along the Colombian-Peruvian-Brazilian border, also has low, creeping habit which forms large mats, no more than .8" [2 cm] tall, single flowered inflorescence, small flowers, sepals .348 to .48" [8.7 to 12.0 mm] long, column .156 to .2" [3.9 to 5.0 mm] long, lip cordiform-sub-orbicular, clinandrium-hood entire, anther ovoid-circular, short, apical margin entire. Epidendrum schlechterianum Ames from Panama and the northwestern slope of the Chocó has a two-flowered inflorescence with relatively long, greenish purple to olive green flowers tinged with red, sepals oblong-lanceolate, .68 to .8" [17 to 20 mm] long, lip cordate-reniform, minutely apiculate, and the column .4 to .56" [10 to 14 mm] long with the anther elongate, sub-acute and apically fimbriate. Epidendrum congestum Rolfe has 2 to 3, much smaller flowers with sepals .28 to .4" [7 to 10 mm] long and the lip cordiform with the apex acute, and the anther widely ovoid and apically truncate, the margin something dentate. Epidendrum congestoides Ames & C.Schweinf. also has a two-flowered inflorescence, but the flowers are smaller, green to reddish green, sepals ovate to ovate-lanceolate, .32 to .52" [8 to 13 mm] long, the lip reniform-semi-orbicular, somewhat embracing the short column .18 to .264" 4.5 to 6.6 mm] long in natural position, and the anther is short, the margin fimbriate." Hagsater etal 2019


References W3 Tropicos, Kew Monocot list , IPNI ; * Icones Orchidacearum 17(1) Plate 1751 Hagsater & Jimenez 2019 Drawing fide