Epidendrum tridens Poepp. & Endl., Nov. Gen. & Sp. Pl. (Poeppig & Endlicher) 2: 2. t. 103. 1838.

Arista, Jessy Patricia, Hagsater, Eric, Santiago, Elizabeth, Edquen, Jose D., Pariente, Eli, Oliva, Manuel & Salazar, Gerardo A., 2023, New and noteworthy species of the genus Epidendrum (Orchidaceae, Laeliinae) from the Area de Conservacion Privada La Pampa del Burro, Amazonas, Peru, PhytoKeys 227, pp. 43-87 : 43

Epidendrum tridens Poepp. & Endl., Nov. Gen. & Sp. Pl. (Poeppig & Endlicher) 2: 2. t. 103. 1838.

Fig. 15

Type material.

Peru. [ Huánuco:] Subandin. supra arbores, Cuchero, E. F. Poeppig s.n. (holotype: W-R!; isotype: W-R 42400!).

Taxonomic synonym.

Epidendrum tunguraguae Schltr. Repert. Spec. Nov. Regni Veg. Beih. 8: 87 (1921). Type: Ecuador. Tunguragua: In rupibus in convalle subandina montis Tunguragua, c. 1800 m, Jun. 1886, L. A. Sodiro 69a (holotype: B, destroyed; illustration AMES36134!; neotype, designated by Sánchez Saldaña and Hágsater in Hágsater and Sánchez Saldaña 2015, t. 1565: Wulkan Tunguragua, 1500-2000 m, blooms in June and July, F. C. Lehmann 6719, K! (pencil illustration of live plant in flower, Lehm. Ic. Pl. Tabul. 438, K!; isoneotype AMES!).

Description.

Epiphytic, lithophytic or terrestrial, sympodial, caespitose, erect herb 26-100 cm tall, including inflorescence. Roots 3-4 mm in diameter, basal, fleshy. Stems 18-56 × 0.6-1.5 cm, simple, cane-like, laterally compressed toward apex, straight, green, sometimes tinged purple. Leaves 4-8, distributed along apical ¾ of stems, erect, coriaceous; plants deep green sometimes tinged purple, especially sheaths and underside of leaves; sheath 2-6 cm long, foliaceous, laterally compressed, ancipitose; blade 8.0-15 × 2-5 cm, unequal, progressively larger toward apex of stem, narrowly elliptic, 3-5 times longer than wide, apically unequally bilobed, minutely mucronate, venation and dorsal keel evident, dark green, occasionally tinged purple. Spathe lacking. Inflorescence apical, racemose, becoming pluri-racemose, producing one flower at a time, over several years from same stem; peduncle 3-4 mm long, reduced, rachis 5-7[10] mm long. Floral bracts 7-11 × 5-6 mm, much shorter than ovary, triangular, acuminate, amplexicaul. Flowers successive, one at a time from each raceme, resupinate, sepals and petals green to yellow, occasionally tinged purple, lip and column white; scented at night. Sepals 42-73 × 5-8 mm, spreading, linear-lanceolate, acuminate, 10-veined, with numerous secondary veins, margin entire, revolute. Petals 40-70 × 2.5-3.0 mm, partly spreading, linear-lanceolate, acuminate, 5-veined, with numerous secondary veins, margins entire, spreading. Lip 27-53 × 24-30 mm, united to column, 3-lobed, margin entire, spreading; bicallose, calli laminar, prominent; lateral lobes 14-26 × 6-9 mm, semi-ovate, rounded; mid-lobe 20-37 × 2-3 mm, ensiform, acute, margin entire. Column 21-25 mm long, straight to slightly arched, strongly dilated toward apex. Clinandrium hood slightly surpassing body of column, generally somewhat dentate, occasionally deeply dentate. Anther obovoid, 4-celled. Pollinia 4, semi-obovoid, laterally compressed; caudicles soft and granulose, about as long as pollinia. Rostellum apical, slit; viscarium semi-liquid, transparent. Lateral lobes of stigma reduced. Cuniculus penetrating nearly half length of ovary, unornamented. Ovary 60-100[120] × 2.0-3.5 [5] mm long including pedicel, shorter to slightly longer than apical leaf, terete, inflated, unornamented. Capsule ellipsoid, slender; pedicel 25-35 × 2.0-2.5 mm, body 45-60 × 17-21 mm, at center of capsule; apical neck 13-16 × 2.3-3.5 mm.

Additional specimens examined.

Peru. Sine loc., Bennett 57 (MOL!); Ibid. loc. Bennett 3669 (MOL!); ibid. loc., 1803, Ruiz & Pavón s.n. (MA!); Sine loc., 1876-1877, Vidal-Sénège 68 (P!); Amazonas: Prov. Bongará, Dist. Yambrasbamba, Perla del Imaza, La Perla Vieja, Arista et al. 9 (KUELAP!); Cajamarca Bongará near Pedro Ruiz, 2200 m, Aug. 1979, Königer 24/1 (SEL!); Bongará, 1 Sep. 1985, Moore s.n. (SEL!); Bongará, Dist., Yambrasbamba, viaje al puente Vilcaniza, 1840-2020 m, 9 Jul. 1999, Sánchez-Vega 10028 (AMO! F!); Ayacucho: Aina, between Huanta and Río Apurimac, 750-1000 m, 7 May 1929, Killip 23169 (US!); Cajamarca: San Ignacio Huarango, Nuevo Mundo, 1140 m, 11 Mar. 2000, Calatayud 425 (CUZ!); San José de la Alianza, Rinconada, 2200 m, 18 Mar. 2009, Vásquez 242 (MOL!) Cusco: Paucartambo, Mirador, Unión-Cosñipata, 1750 m, Feb. 1994, Moscoso 760 (CUZ!) Paucartambo, San Pedro-Cosñipata, 1480 m, Mar. 1994, Moscoso 1112 (CUZ!); ibid. loc., Mar. 1994, Moscoso 1113 (CUZ!); Quispicanchis, Río Arazá, between Pan de Azúcar and Quince Mil Airport. 292 km from Cusco, 643 m, 10 Aug. 1991, Nuñez 14065 (MO!); Marcapata, Murayaca, Quispicanchis, 1685 m, 6 Nov. 2006, Villafuerte 620 (CUZ!); Huánuco: Leoncio Prado, La Alcantarilla, Tingo Maria , 650 m, 6 Jul. 1984, Fernández 385 (USM!); Carpish, entre Huánuco y Tingo María, 2800-2900 m, 6 Feb. 1950, Ferreyra 6713 (AMES! UC! USM!); Carpish pass, Tingo Maria side, 2000 m, 18 Jul. 1964, Hutchison 5977 (UC! US!); Carpish Hill, between Huánuco and Tingo María, 2100 m, 10 Aug. 1980, Luer 5351 (SEL!); Carpish, km 453, 2500 m, 7 May 1976, Plowman 6070 (AMES!); San Pedro de Carpish , Mirador, Ridoutt s.n. (USM!); Chinchao-Carpish, 2400 m, Woytkowski 5024 (MO! AMES!); Junín: Chanchamayo, La Merced, Quebrada del Carmen , 850 m, 6 May 1984, Fernández 305 (USM!); Chanchamayo, El Refugio, San Ramón, 800 m, 16 May 1984, Fernández 318 (USM!); Tarma, Agua Dulce, 1900 m, 16 Mar. 1948, Woytkowski 35478 (MO!); Loreto: Coronel Portillo, Divisoria, entre Tingo María y Pucallpa, 1500-1600 m, 28 Feb. 1947, Ferreyra 1677 (USM!); Pasco: Chontabamba, La Suiza Nueva, 2190-2200 m, 7 Jan. 2005, Arias 70 (HOXA! MO!); Oxapampa , Sector San Alberto, P [arque]. N[acional]. Yanachaga-Chemillén, 2100 m, 18 Mar. 2005, Ortiz 507 (HOXA! MO!); Oxapampa , Huancabamba, localidad Grapanazu, Sector San Daniel, P [arque]. N[acional]. Yanachaga-Chemillén, 2236 m, 10 Jul. 2004, Perea 1476 (HOXA! MO!); Oxapampa , Chontabamba valley , 23 km W of Oxapampa 1900 m, 26 Jan. 1984, Smith 5881 (MO! USM!); Huancabamba, Parque Nacional Yanachaga-Chemillén, Sector Quebrada Yanachaga. 1700-2265 m, 17 Feb. 2004, Vásquez 29534 (HOXA! USM!); Puno: Carabaya, San Gaban, alrededores de San Gaban, 1810 m, 9 Mar. 2017, Trinidad 4134 (USM!); alrededores Sandia, 2250 m, 5 Feb. 1964, Vargas 15149 (AMES! CUZ!); San Martín: Cordillera Azul, Coronel Portillo, Tingo Maria on highway to Pucallpa , near Divisoria, ca. 1600 m, 17 Nov. 1949, Allard 21786 (AMES! US!); Ucayali: Padre Abad, Parque Nacional Cordillera Azul, Divisoria, entre Tingo María y Pucallpa, 1500 m, 28 Feb. 1947, Ferreyra 1677 (USM!) .

Other records.

Peru. Sine loc., illustration by I. Pulgar, Ruíz and Pavón 1282 (MA!); Jaén: Ocupa-Horna s.n., color plate (AMO!); San Martín: Moyobamba above Naranjo at km 468 along Olmos-Moyobamba road, 1020 m, 9 Dec. 1990, Bennett 4800, illustration in Icon. Orchid. Peruviarum t. 51 ( Bennett and Christenson 1993); Bosque de Protección Alto Mayo, Jan. 2015, Collantes s.n., digital images (AMO!); Rioja: Pardo Miguel Naranjos, Venceremos, 1887 m, 6 Feb. 2017, Edquén 1088, digital images (AMO!); ibid. loc., 1750 m, 26 May 2022, Edquén 6038, digital images (AMO!).

Distribution.

Widespread on the Amazonian slope of the eastern Andean range in Colombia, Ecuador, and Peru, and further northeastern into the Guiana Shield in Venezuela, at 640-2900 m.

Habitat and ecology.

Usually growing as a terrestrial or lithophytic on roadside embankments and sometimes epiphytic in montane wet forest and dwarf forest on white sand.

Phenology.

Flowering throughout the year, fruiting mainly from June to September.

Taxonomic notes.

Epidendrum tridens belongs to the Nocturnum Group which is characterized by the sympodial, caespitose plants, cane-like, non-fusiform stems, successive flowers on a short, racemose or pluri-racemose inflorescence, without spathaceous bracts, and large, star-shaped flowers, with similar sepals and petals; the flowers are mostly indistinguishable in shape. The species is recognized by the dark green plants, the underside of the leaves and sheaths tinged with purple, laterally compressed stems, 4-8 erect leaves, generally longer toward the apex of the stem, length/width 3:1-5:1 (8.5-15 × 2-5 cm), distributed along the apical ¾ of the stems, green often tinged with purple; the ovary 60-100 [120] mm long, equal or occasionally longer than apical leaf, the sepals 42-73 mm long, the lateral lobes of lip semi-ovate, rounded to acute, acuminate, 14-26 mm long; the mid-lobe 20-37 mm long, the column 21-25 mm long; body of the capsule centered. Epidendrum nocturnum Jacq. is widely distributed from Florida to Bolivia, has green plants, terete stems, smaller leaves distributed along the apical 2/3 of the stems, a short ovary, 50-70 mm long, and the body of the capsule occupying nearly its whole length. Epidendrum tumuc-humaciense (Veyret) Carnevali & G.A.Romero is found along the Guiana Shield, and at lower altitudes in the Amazon basin in Colombia, Venezuela, Guyana, Surinam, French Guiana and the northern border of Brazil. Plants are frequently vinaceous, or yellow-green, it has numerous, shorter, narrower, erect leaves (3-9.2 × 1.2-2.8 cm), distributed throughout the stems, the basal ones generally longer; sepals and petals 48-81 mm long; body of the capsule occupying the apical half of the fruit.

Figures

Figure 15. Epidendrum tridens from Arista et al. 9 A habit B flower C dissected perianth D developing capsule E column and ovary-pedicel from below (left) and side (right) F anther from above (left) and below (right), and pollinarium (Photographs by J. D. Edquen; plate prepared by A. Cisneros).