Epidendrum polythallum Est.Domínguez, J.S.Moreno, Hágsater et E.Santiago, Icon. Orchid. 15(2): t. 1593. 2016.
Type: Colombia. Antioquia: Municipio de Urrao; Cordillera Occidental, camino entre Urrao y el Carmen de Atrato (Chocó), Alto de la M, La Fragua, 2500 m, 26 June 2015, E. Domínguez Vargas 396 (holotype: JAUM; LCDP voucher).
Epidendrum polythallum is recognized by the much branched stems, with a tall primary stem, numerous secondary and tertiary stems, the nodding in orescence bears only 3-4 pale yellow flowers, lip wine-red except for the calli and apices of the lobes which are pale yellow, sepals connate at base, narrowly oblanceolate, petals linear, obliquely acute at the apex, lip deeply 3-lobed, with 5 parallel ribs on the disc and a pair of radiating shorter ribs on the lateral lobes which are obliquely triangular. The flowers are reminiscent of E. amplexirisaraldense Hágsater & E. Santiago, but the plant habit of that species is not branched, the new stem orig- inating from a sub-apical internode of the previous stem; flowers are greenish. The plant habit of the new species is reminiscent of E. paraguastigma Hágsater & García-Cruz which also has a tall primary stem, numerous, progressively smaller secondary stems and numerous smaller tertiary stems, but that species has 7–9, simultaneous, concolor, white owers, sepals 6.5–7.6 mm long, and an entire, cordiform lip with a “Y” shaped callus. It is known presently only from Colombia, Antioquia, along the summit of the Cordillera Occidental, near the border of the Chocó, epiphytic near the base of a bush at the edge of a wet montane forest, on clis and road-side slopes, at 2500 m elevation. Flowering was recorded in February. . .