Epidendrum holtonii Hágsater & L.Sánchez 2009 GROUP Difforme

Photo by © Guillermo Alberto Reina-Rodríguez Revista Occidental Website

TYPE Drawing

TYPE Drawing by © Jimenez and The AMO Herbaria Website

Part Shade LATE Summer EARLYFall

Common Name Holton's Epidendrum [English Orchid Collector in Colombia 1800's]

Flower Size 1.4" [3.5 cm]

Found in central Colombia without elevational data as a small sized epiphyte with simple, cane-like, ancipitous, straight stems carrying 5 to 6, all along the stem, elliptic, acute, prominent dorsal keel, coriaceous, margin entire leaves that blooms in the late summer and early fall on a terminal, erect, on a mature stem, occuring only once, subcorymbose, sessile, simultaneously, 4 to 5 flowered inflorescence with much shorter than the ovary floral bracts and carrying resupinate, green flowers.

Thought to be extinct since its original collection in 1853, officially described by Hagsater and Sanchez in 2009 from the type collection stored in the New York Botanical Garden Herbarium, this orchid was rediscovered in the wild in 2018 by a group from the Universidad del Valle in Colombia led by Guillermo Alberto Reina-Rodríguez.

"Epidendrum holtonii belongs to the GROUP Difforme, which is characterized by the sympodial, caespitose habit, fleshy, light green to glaucous leaves, apical, sessile inflorescence lacking spathaceous bracts, rarely with a short peduncle, inflorescence one-flowered to sub-corymbose, flowers green to yellowish-green, rarely white. The species is recognized by the ancipitose stems, and the transversely elliptic-reniform to obscurely 3-lobed lip, the base deeply cordate, the basal margin undulate, lateral lobes elliptic, midlobe very small, forming two small, rounded lobes, the apex with a wide, apiculate sinus, and the small, divergent calli. It is similar to Epidendrum yaracuyense, from Venezuela, which has the apex of the leaves apiculate, the lip reniform, only slightly cordate at the base, margin entire, with two small, sub-globose calli and an arched column. Other species which could be confused with this species grow in the Amazon basin of Peru such as E. apaganoides D.E.Benn. & Christenson which has a 3-lobed lip, the disc fleshy, and a slightly arching column. Epidendrum apaganum Mansf. has smaller leaves, the lip 3-lobed, small, sub-globose calli, and the disc of the lip with numerous thickened veins. Epidendrum pseudoapaganum D.E.Benn. & Christenson has large plants with numerous flowers, and the lip reniform without thickened veins." Hagsater etal 2009


References W3 Tropicos, Kew Monocot list , IPNI ; * Icones Orchidacearum 12 Plate 1254 Hagsater & Sanchez 2009 drawing fide; Orchids of the Department of Valle de Cauca Colombia Vol 2 Kolanowska, Hagsater, Ayala and Saldana 2014 drawing/photo fide; Orquideas, Tesoro de Colombia Vol 2 Ortiz & Uribe 2017; Icones Orchidacearum 18(2) Plate 1854 Hagsater & Jimenez 2021 see recognition section