Epidendrum pomacochense Hagsater , Icon. Orchid. 3: t. 374. 1999.

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 pomacochense Hagsater, Icon. Orchid. 3: t. 374. 1999.

Fig. 13

Type material.

Peru. San Martín: Mirador, between Moyobamba and Pomacochas, just before Pomacochas, 1700 m, pressed 23 Nov. 1993, hort. J. & L. Orchids sub E. Hágsater 11391 (holotype: AMO!).

Description.

Epiphytic or lithophytic, monopodial, branching, erect herb, 15-20 cm tall. Roots 1-2 mm in diameter, basal from primary stem, fleshy, thin. Stems 12-18 × 0.15-0.4 cm, cane-like, terete, branching, branches produced from sub-apical internodes of previous stems, progressively shorter. Leaves 3-13 per stem, distributed along apical half of primary stem, and aggregate toward apex in shorter branches, distichous, articulate, sub-coriaceous, green, concolor; sheathes 0.6-1.2 cm long, tubular, striated, red; blade 1.2-4 × 0.3-0.4 cm, linear-lanceolate, apex unequally bilobed, margin entire, spreading. Spathe lacking. Inflorescence to 3 cm long including flowers, apical, racemose, arching-nutant, densely few-flowered; peduncle 6-8 mm long, terete, thin, scarcely verrucose. Floral bracts 2.0-2.5 mm long, much shorter than ovary, narrowly triangular, embracing. Flowers up to 9, resupinate, successive, 2-3 open simultaneously, sepals and petals copper-red, lip dark brick-red, with disc and column yellow, anther yellow slightly tinged brick-red on sides; fragrance none registered. Sepals partly spreading, free, membranaceous, dorsally scarcely verrucose, not carinate, 3-veined, somewhat concave, margins entire, spreading; dorsal sepal 4.6-5.5 × 3.1-4.3 mm, widely elliptic, apex rounded-obtuse; lateral sepals 5.5-7.0 × 3.8-5.5 mm, obliquely ovate, apex obtuse. Petals 4.2-6 × 1-1.5 mm, partly spreading, free, membranaceous, linear-lanceolate, obtuse, 3-veined, margin entire, spreading. Lip 7-8.4 × 6.7-9 mm, united to column, shallowly 3-lobed, transversely elliptic in outline, concave, base cuneate; ecallose, disc 5-ribed, smooth, parallel, 3 mid-ribs reaching middle of lip, lateral pair shorter; lateral lobes semi-orbicular, mid-lobe smaller, formed by two small semi-orbicular lobes, emarginate. Column 4 mm long, slightly arched with apex recurved upward, thick, apical aperture wide, triangular. Clinandrium hood short, margin entire. Anther 4-celled, obreniform, papillose. Pollinia 4, obovoid, laterally compressed, subequal, cream-colored; caudicles soft and granulose, as long as pollinia. Rostellum subapical, slit; viscarium semi-liquid. Lateral lobes of stigma small. Cuniculus a very wide cavity formed by column and lip, triangular, reaching perianth, unornamented, with a longitudinal widened slit ventrally at base of column. Ovary 6-9 mm long, terete, thin, not inflated, furrowed and scarcely verrucose. Capsule not seen.

Additional specimens examined.

Peru. Amazonas: Perla del Imaza, La Perla Vieja, 1863 m, 22 Aug. 2021, Arista et al. 38 (KUELAP!); Perla de Imaza , Rio Rojo , 1875 m, 25 Aug. 2021, Arista et al. 108 (KUELAP!); road Chachapoyas-Mendoza, a little past Molinopampa, 2400 m, 15 Mar. 1998, van der Werff 15019 (SEL!) ; San Martín: Bosque de protección Alto Mayo. Sector Venceremos, 1955 m, 21 Feb. 2017, Edquén 195 (UNACH!) Prov. Rioja, Distrito Pardo Miguel, Chisquilla, 3278 m, 11 Apr. 2019, Edquén 1810 (UNACH!) .

Other records.

Peru. Sine loc., Jenny s.n., digital image (AMO!); Amazonas: Rodríguez de Mendoza, 30 Jan. 2017, Arbilo s.n., digital image (AMO!); Huamantapa, R[ odríguez]. de Mendoza, 9 Apr. 2015, Fernández s.n., digital image (AMO!); Área de Conservación Pampa del Burro, camino a Perla del Imaza, km 14.5, 1823 m, 14 Jul. 2022, Hágsater 16407, digital image (AMO!); ibid. loc., km 16, 1837 m, 15 Aug. 2022, Hágsater 16428, digital image (AMO!); Cajamarca: Prov. Cajabamba, Parubamba, 2600 m, 10 Dec. 2005, Trujillo 243, illustrated by M. Alcántara 1558, copy of illustration (AMO!); San Martín: Prov. Rioja, Distr. Pardo Miguel Naranjos, Venceremos, 1699 m, 21 Feb. 2017, Edquén 2025, digital images (AMO!); ibid. loc., Edquén 2026, digital images (AMO!); ibid. loc., Edquén 2027, digital images (AMO!); ibid. loc., Edquén 2028, digital images (AMO!).

Distribution.

Known only from northeastern Peru, in Amazonas, San Martin and Cajamarca where it is common in protected areas with wet Andean forests, at 1700-2000 m.

Habitat an ecology.

Epiphytic in humid montane forest, sclerophyllous shrubs, and very wet dwarf forest, and lithophytic on road-side banks of white sand and sandstone.

Phenology.

Flowering from January to August.

Taxonomic notes.

Epidendrum pomacochense belongs to the Diothonea Group and Subgroup, which is characterized by the monopodial, branching plants, the linear lanceolate to oblong, bilobed leaves, the racemose, arching-nutant inflorescence, the membranaceous flowers (rarely fleshy), the entire to 3-lobed, ecallose lip with the margin erose without or with 1-10 thin, smooth to erose keels, the column completely to obliquely united to the lip, and the anther reniform. Epidendrum pomacochense is recognized by the small plants, 15-20 cm tall, the copper-red flowers with the disc of the lip and column yellow, the sepals 4.6-7 mm long, dorsally sparsely verrucose, the column short and forming a large triangular aperture with the lip, the lip 3-lobed, transversely elliptic, the disc of the lip 5-ribbed, the ribs low, rounded, the 3 central ribs reaching the middle of the lip, the lateral lobes semi-orbicular, the mid-lobe smaller, formed by two small semi-orbicular lobes, emarginate. Epidendrum cochabambanum Dodson & Vásquez has larger plants up to 30 cm tall, linear leaves to 4.5 cm long, the inflorescence up to 4 cm long with flowers white tinged pink, and the lip 5-ribbed, the ribs high and apically truncate. Epidendrum stenophyllum Hágsater & Dodson is florally similar but the plants are up to 55 cm tall, with linear leaves, nearly acicular, 2-5.5 × 0.2-0.3 cm, the sepals up to 10 mm long.

Figures

Figure 13. Epidendrum pomacochense from Arista et al. 38 A habit B flower C dissected perianth D inflorescence at apex of stem E longitudinal section of flower F column and ovary-pedicel from below (left) and side (right) G anther from above (left) and below (right), and pollinarium (Photographs by J. D. Edquen; plate prepared by A. Cisneros).