Epidendrum mavrodactylon Hagsater , Edquen & E.Santiago, Icon. Orchid. 16(2): t. 1682. 2018.

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 mavrodactylon Hagsater, Edquen & E.Santiago, Icon. Orchid. 16(2): t. 1682. 2018.

Fig. 9

Type material.

Peru. San Martín: Prov. Rioja, correspondiente al área natural protegida Bosque de Protección Alto Mayo-BPAM, Sector Venceremos, Zona 18, 1807 m, 30 Jan. 2018, J. D. Edquén 401 (holotype: HURP!).

Description.

Epiphytic, caespitose, sympodial, compact, small, reclining herb, 3 cm tall. Roots 1 mm in diameter, basal along rhizome, thin, white. Stems 1.3-2 × 0.3-0.4 cm, cane-like, simple, laterally compressed, somewhat reclining. Leaves 4-7, fleshy, distichous, erect, semi-terete, concave, arching and partially imbricated, somewhat conduplicate, dark green, concolor; sheath 1-3 mm long, tubular, narrow at base gradually widened toward apex; blade 0.5-1.4 × 0.2-0.4 cm, narrowly lanceolate obtuse to sub-acute, minutely apiculate, margin entire, dentate at apex. Spathe 1, 5-9 × 5-7 mm when spread, elliptic, obtuse, minutely apiculate, conduplicate. Inflorescence apical, sessile, single-flowered. Floral bract not seen (hidden within spathe). Flower 1, resupinate yellowish green, sepals and petals with a bronze tinge; fragrance not registered. Sepals 8-10 × 3.0-4.0 mm, apex acuminate, minutely apiculate, 3-veined; dorsal sepal free, partly spreading, nearly parallel to column, narrowly lanceolate, margin minutely papillose toward apex, spreading; lateral sepals obliquely untied to base of column, spreading, narrowly ovate-triangular, oblique, margin entire, revolute. Petals 8-8.5 × 0.5 mm, free, partly spreading, parallel to dorsal sepal, linear, falcate, acute, 1-veined, margin entire, spreading. Lip 7.0-7.2 × 4-5 mm, united to column, entire, elliptic, base cuneate, apex acute, minutely apiculate, margin slightly erose; bicallose, calli globose, prominent; disc with a very low midrib. Column 4 mm long, thin at base, gradually wider toward apex, triangular in lateral view. Rostellum apical, slit; viscarium semi-liquid, white. Clinandrium hood prominent, slightly longer than body of column, totally covering anther, margin erose. Anther reniform, 4-celled. Pollinia 4, obovate, complanate, convex-flat, caudicles as long as pollinia. Lateral lobes of stigma not seen. Cuniculus inflated ventrally along apical half of ovary. Ovary 11-15 mm long, ventrally inflated, forming a prominent, elongate vesicle along apical, ventral half of ovary. Capsule not seen.

Additional specimens examined.

Peru. Amazonas: Prov. Bongará, Distr. Yambrasbamba, Perla del Imaza , 1763 m, 28 Aug. 2021, Arista & Edquén 156 (KUELAP!) .

Other records.

Peru. Cultivated in Moyobamba in the private collection of José Altamirano, 16 May 2009, digital images, Jenny s.n. (AMO!).

Distribution.

Known presently only from northern Peru, from the limits between the departments of San Martín and Amazonas. On both sides of the ridge that forms the border of the two departments. In montane wet forest at 1763-1800 m elevation.

Habitat and ecology.

Epiphytic on Erythrina L. Ground with abundant moss, and accumulation of organic matter.

Phenology.

Flowering in January to August.

Taxonomic notes.

Epidendrum mavrodactylon represents an addition to the orchids of the department of Amazonas. It belongs to the Porpax Group, which is characterized by the sympodial, somewhat repent habit, usually forming large mats; the short, cane-like stems with very fleshy, succulent, articulate, distichous leaves, the apical margin minutely ciliate; the single-flowered inflorescence with sessile flowers; and the lip generally reddish purple. Epidendrum mavrodactylon is recognized by the very small plants, up to 3 cm tall, with leaves 0.5-1.4 cm long, semi-terete, concave and arching, flowers yellowish green, sepals and petals tinged bronze; dorsal sepal and petals nearly parallel to the column, lip 7.0-7.2 × 4-5 mm, elliptic, acute, and the ovary with a prominent ventral, elongate vesicle, half as long as the ovary. Epidendrum althaniorum Hágsater & Collantes from Cusco has larger plants, 4.5-10 cm tall, leaves 1.3-5 cm long, straight, flowers lime-yellow, lip orbicular, rounded with a heart-shaped red blotch in the middle, and the ovary not inflated, not forming a vesicle. Epidendrum neolehmannia Schltr. of the same group has an equally inflated vesicle ventrally along the ovary caused by the inflated cuniculus, but the flowers have a cordiform lip 12-15 × 12-17 mm, with two parallel calli at the base, no obvious mid-rib, and the leaves are semi-terete, 1.0-2.5 × 0.4-0.7 cm.

Figures

Figure 9. Epidendrum mavrodactylon from Arista et al. 156 A habit B flower C dissected perianth D flower 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).