Epidendrum tridens Poepp. & Endl.

  • Authority

    Ackerman, James D. 1995. An orchid flora of Puerto Rico and the Virgin Islands. Mem. New York Bot. Gard. 73: 1-203.

  • Family

    Orchidaceae

  • Scientific Name

    Epidendrum tridens Poepp. & Endl.

  • Description

    Species Description - Plants glabrous epiphytes or lithophytes, extending somewhat horizontally from their substrate. Roots numerous produced from short rhizome, fleshy, 2-3.5 mm diam. Stems few, clustered, canelike, ancipitous, to 40 cm long, covered by persistent, flattened sheaths 1.1-5.6 cm long, 9-12 mm wide. Leaeves 1-6, distichous; blades coriaceous, entire, oblong-elliptic, obtuse-rounded, 10-18 cm long, 2.2-4 cm wide. Inflorescences terminal, subsessile racemes, 1- to 4-flowered. Flowers large, produced in succession, one at a time, opening partially (in ours). Pedicellate ovary slender, 8-11 cm long. Sepals and petals pale green, entire. Dorsal sepal linear-lanceolate or linear-elliptic, acuminate, 57-75 mm long, 3- 7 mm wide; lateral sepals similar but narrower. Petals filiformlinear, 51-73 mm long, 2-5 mm wide. Lip adnate to the full length of the column, lamina white, trilobed, overall 45-61 mm long, 10-13 mm wide; lateral lobes obliquely lanceolate, basally rounded in lower half, 4-7 mm wide, above linear-acuminate and 25-35 mm long; middle lobe linear-filiform, 37-56 mm long, ca. 1.5 mm wide; disc callus bilobed, ca. 9 mm long, flanking the entrance to the floral tube. Column 16-22 mm long; anther operculate; pollinia 4, yellow. Fruit pedicel ca. 2 cm long; capsule ellipsoidal, ca. 8 cm long; beak prominent, 2-4 cm long, overall fruit length 10-13.5 cm.

    Distribution and Ecology - General Distribution. Colombia, Cuba, French Guiana, Guyana, Peru, and Puerto Rico, Surinam. Distribution in Puerto Rico. Known from Adjuntas, Bayamon, Canovanas, Cayey, Luquillo, Maricao, Naguabo, Orocovis, Patillas, and Rio Grande. Habitat. Epiphytic on tree trunks or lithophytic on boulders in moist and wet forests from low to high elevations (300-850 m) in the Luquillo Mountains to the Cordillera Central. Locally common but sparsely distributed.

  • Discussion

    9. Epidendrum tridens Poeppig & Endlicher, Nov. Gen. Sp. PL 2: 2, t. 103. 1838. Epidendrum nocturnum var. tridens (Poeppig & Endlicher) Cogniaux, in Martius, Fl. Bras. 3(5): 136. 1898. Type. Poeppig & Endlicher s.n., from Cuchero, eastern Peru, Jan 1830 (W, photocopy seen). Phenology & Pollination. Flowering occurs from late spring to early summer. In Puerto Rico self-pollination probably occurs because flowers scarcely open yet fruits usually develop. Two successive shoots often bear fruit at the same time because inflorescences may produce flowers for more than one season. Seeds are dispersed in the fall. Taxonomic Notes. Cogniaux and Urban (1903) listed this species as a variety of Epidendrum nocturnum for Puerto Rico, but subsequent authors have placed it in synonymy with that species. After careful study, we (Ackerman, Morales & Melendez, unpubl.) find no morphological intermediates between the closely related E. tridens, E. carpophorum, and E. nocturnum, even at sites in the Luquillo and Cayey mountains, where the three grow together. In addition, E. tridens flowers at a different time of year than the other two species. Eric Christenson suggests (pers. comm., 1993) that E. tridens is a terrestrial plant with a strict upright habit, at least in the Guianas. Our plants grow on rocks and tree trunks, as Poeppig and Endlicher originally described. Although they described E. tridens from a Peruvian specimen, their description and illustration published seem representative of our plants.