Epidendrum rigidiflorum Schltr. 1923 GROUP Macrostachyum SUBGROUP Stenophyton

TYPE Drawing © by M Lopez R and The AMO Herbaria Website

Common Name The Rigid Flower Epidendrum

Flower Size .8" [2 cm]

Found in Costa Rica at elevations of 1300 to 2000 meters as a giant sized, cool growing terrestrial with sparsely branching subapically, cane-like, terete, thick, straight stems enveloped by leafless in the lower 1/3 and leaf bearing sheaths in the upper 2/3's and carrying to 22, articulate, alternate, unequal, lanceolate, acuminate, coriaceous, apical margin denticulate leaves that blooms in the summer through winter on a terminal, erect, racemose, flowering only once, distichous, secund, terete, thin, straight, 4" [10 cm] long, 10 to 19 flowered inflorescence with lanceolate, acuminate, coriaceous, apically gradually shorter floral bracts that are twice as long as the ovary and carrying nocturnally fragrant, simultaneously opening, non-resupinate, secund, fleshy, rigid flowers.

"Epidendrum rigidiflorum belongs to the GROUP Macrostachyum , which is characterized by the monopodial plants with subapical branching, rugose leaf sheaths, racemose inflorescence, and fleshy flowers with a simple, conduplicate lip embracing the column, and the SUBGROUP Stenophyton which has a distichous inflorescence with secund, non-resupinate flowers, the lip entire, triangular to cordiform, and the nectary pubescent in front of the stigmatic cavity. The species is recognized by the large, scarcely branching plants, the lanceolate leaves, 3 to 7.2" [7.5 to 18 cm] long, distichous and secund inflorescence, 6 to 9.2" [15 to 23 cm] long, the large floral bracts .44 to .88" [11 to 22 mm] long and yellow, yellowish brown to greenish yellow, large flowers with sepals .4 to .48" [10 to 12 mm] long, and the lip widely ovate-cordiform with a cordate base. It is closely related to Epidendrum microrigidiflorum Hágsater from Costa Rica and Panama, which is overall smaller, the leaves ovate-lanceolate, .64 to 3.2" [1.6 to 8 cm] long, small flowers with sepals .28 to .31" [7.0 to 7.8 mm] long and petals greenish-yellow with the lip orange, sometimes somewhat greenish, and the lip widely rhombic, the base widely cuneate. Both have been confused with the South American Epidendrum chondrochilum syn Epidendrum macrostachyum Lindl. which has similar flowers, but a racemose, cylindrical inflorescence." Hagsater etal 2008


References W3 Tropicos, Kew Monocot list , IPNI ; *Repert. Spec. Nov. Regni Veg. Beih. 19; 127. Costa Rica Schlechter 1923; The Genus Epidendrum Ames 1936; Ceiba Vol 5 No 1 L O Williams 1956; Orchids of Peru Vol 2 Fieldiana Schweinfurth 1959; Flora de Venezuela Vol XV Tercera Parte Foldats 1970 drawing fide; Manual de las Plantas de Costa Rica Vol 3 Hammel, Grayum, Herrera and Zamora 2003; Icones Orchidacearum Vol 8 Plate 853 Hagsater & Sanchez 2006 see recognition section; Icones Orchidacearum 11 Plate 1174 Hagsater & Sanchez 2008 drawing fide; Orchids of Costa Rica Vol 2 Morales 2009 photo fide;