Epidendrum weigendii Hagsater & Cisneros, Icon. Orchid. 18(2): t. 1899. 2021.

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 weigendii Hagsater & Cisneros, Icon. Orchid. 18(2): t. 1899. 2021.

Fig. 16

Type material.

Peru. Amazonas: Chachapoyas: Molinopampa: Road Chachapoyas to Mendoza, km 36, cloud forest, on sandstone, 2800 m, 5 June 1998, M. Weigend, T. Franke, J. Skrabal & M. A. González 98/429 (holotype: F-2211499!; isotype: USM!).

Description.

Epiphytic, sympodial, scandent, erect herb up to 58 cm tall, new stems produced from a middle internode of previous stem. Roots fleshy, from base of primary stem or occasionally from base of upper stems. Stems 8-15 × 0.3-0.5 cm, erect, simple, cane-like, terete, basal 3/4 of stem covered with non-foliar sheaths. Leaves 2-3, aggregate toward apex of stem, spreading, alternate; sheaths 0.6-2.5 × 0.3-0.5 cm, tubular, striated; blades 2.1-9.6 × 0.9-2.1 cm, unequal in size, elliptic-oblong, acute, sub-coriaceous, medium green. Spathe lacking. Inflorescence 4-6 cm long, apical, from mature stem, racemose, arcuate; peduncle 1.4-2.3 × 0.3 cm, somewhat laterally compressed, sometimes with a single bract near base, 8 mm long, acute, embracing; rachis 2.3-5 cm long, arching-nutant. Floral bracts 3-6 mm long, much shorter than ovary, decreasing in size, triangular, acute, embracing. Flowers 7-11, opening in succession, until most open at same time, resupinate, facing downward, medium green, lip pale green, apex of column around anther slightly tinged purple, anther green; fragrance none. Sepals free, spreading, fleshy, 5-veined, margins entire, spreading; dorsal sepal 13-16 × 5.4-6.0 mm, narrowly obovate, obtuse; lateral sepals 14.5-15.0 × 5.4-6.0 mm, obliquely oblong oblanceolate, somewhat falcate, acute. Petals 13.5-16 × 3.5-6.0 mm, free, spreading, oblanceolate, apex sub-acute to rounded, 3-veined, margin entire, spreading. Lip 14.8 × 17.7 mm, united to column, deeply 3-lobed, fleshy, wider than long, base strongly cordate, apex emarginate, margin entire, spreading; bicallose, calli globose, slightly separate, conspicuous, disc with three parallel, thick, low ribs running down middle, lateral ribs arching closer to mid-rib at apex, reaching apical sinus of lip; lateral lobes 7.0 × 8.0-9.0 mm, semi-orbicular; mid-lobe 6.7 × 10.9-12.5 mm, formed by two small, semi-orbicular lobes, with a short, narrow isthmus 1.6 mm long. Column 10 mm long, somewhat thick toward apex, truncate, straight. Clinandrium hood reduced, margin entire. Anther globose, apex emarginate, apical surface minutely echinate, 4-celled. Pollinia obovoid, laterally compressed, subequal; caudicles granulose, shorter than pollinia. Rostellum apical, slit; viscarium semi-liquid. Lateral lobes of stigma not seen. Cuniculus penetrating the apical one third to one half of the pedicellate ovary. Ovary 16-20 × 3 mm, slightly inflated ventrally along apical half, thin, terete, somewhat arcuate, furrowed. Capsule [immature] 45 × 0.6 mm long, narrowly ellipsoid; pedicel 0.7 × 0.2 mm, body 25-30 × 0.6 mm.

Additional specimens examined.

Peru. Amazonas: Prov. Bongará: Distr. Yambrasbamba: Pampa del Burro, Perla del Imaza, a 100 m de la carretera, en bosque chaparro esclerófilo, 1886 m, 14 Aug. 2022, Arista et al. 253 (KUELAP!); Chachapoyas: Molinopampa : along Rio Ventilla , 1-2 km W of Molinopampa, 2350-2400 m, 23 Aug. 1962, Wurdack 1485 (US!) .

Distribution.

Known presently from three collections from the ACPPB and from near Molinopampa, Amazonas, on the border with San Martín, northeastern Peru, 1800-2800 m.

Habitat and ecology.

Epiphytic in dwarf forest on white sand of Andean tepui, dwarf sclerophyllous forest and cloud forest.

Phenology.

Flowering from June to August.

Taxonomic notes.

Epidendrum weigendii belongs to the Incomptum Group. It is recognized by the very thin stems, 2-3 elliptic-oblong leaves aggregate at the apex, the successive flowers, until most open at same time, the flower green, the lateral lobes of the lip orbicular, as are the two lobes of the mid-lobe, the disc of the lip with 3 short parallel ribs, and the short radiating ribs at base of lateral lobes. Epidendrum tamaense has the floral segments strongly reflexed and a strongly arcuate ovary, sepals 15-21 mm long, lateral sepals acute to acuminate, with a conspicuous dorsal keel, petals obtrullate, and the lip larger, 22-24 × 33 mm, bicallose, with a single mid-rib.

Figures

Figure 16. Epidendrum weigendii from Arista et al. 253 A habit B flower C dissected perianth D inflorescence at apex of stem E column with ovary-pedicel from side F column and ovary apex from above (left) and below (right) G pollinarium and anther from above (up) and below (down) H floral bract (Photographs by J. D. Edquen; plate prepared by X. Alcantara).