Epidendrum viridi-ochraceum Zambrano, Hágsater & Solano, 2021

Romero, Bosco Javier Zambrano, Hágsater, Eric & Solano, Rodolfo, 2021, Miscellaneous of new species in Epidendrum (Orchidaceae) from southwestern Ecuador, Phytotaxa 511 (2), pp. 111-114 : 111-114

Epidendrum viridi-ochraceum Zambrano, Hágsater & Solano , sp. nov. Figs. 20–22

Species haec Epidendrum cardiophorum Schlechter (1911: 214) similis sed sepalo dorsali oblongo-lanceolato, acuto, petalis linearoblanceolatis, 3-nervia, labello obovato-pandurato, acuto differt.

Type:— ECUADOR. El Oro: Cantón Piñas, Piedras , camino antiguo El Carmen-La Bocana , 237 m, 26 May 2014, Zambrano B. 1321 (holotype, QCNE; isotype, QCNE-spirit) .

Epiphytic, erect, sympodial, rhizomatous herb, up to 15 cm tall including the inflorescence. Roots 1.0– 1.5 mm in diameter, emerging from the rhizome, fleshy, flexuous, white. Rhizome 2.5–3.5 cm long between adjacent stems, terete, with 3–4 internodes, covered by imbricate, chartaceous, persistent sheaths. Stems 7.5 × 0.25–0.3 cm, canelike, terete at the base and laterally compressed above, erect, base covered by 2–3 laterally compressed, persistent, chartaceous, brown non-foliar sheaths. Leaves 3.5–7.0 × 0.9–1.2 cm, 3–4 distributed along the apical half of the stem, fleshy, coriaceous, distichous, articulate with the sheaths, narrowly oblong, obtuse, minutely mucronate at the apex, channeled at the base; sheaths 0.8–1.5 × 0.35–0.4 cm, longitudinally striated, persistent, chartaceous. Inflorescence up to 6.5 cm long, arising from the apex of the mature stem, erect, simple, distichous; peduncle 2.0– 2.4 cm long, laterally compressed, covered by chartaceous bracts 18–20 × 3.8–4.0 mm, conduplicate, persistent; rachis 2.5–3.0 cm long, laterally compressed; floral bracts 8–10 × 3–4 mm, shorter than the ovary, longitudinal striate when dry, laterally compressed, obtuse, persistent, scarious, with a prominent dorsal keel. Flowers 3–4, small, opening in succession and, eventually all open at one time, non-resupinate, the lip always oriented towards the apex of the rachis; producing a sweet odor at night, the sepals, petals and the lip ochre-orange, callus green, column light green, anther cream colored suffused with green. Sepals spreading in natural position, fleshy, slightly convex longitudinally, margin entire; dorsal sepal 9.8–10.0 × 2.5–2.7 mm, oblong-lanceolate, acute, 8-veined, with the lateral veins branched; lateral sepals 9.8– 10.0 × 2.8–3.0 mm, obliquely oblong-lanceolate, acute, carinate dorsally, 9-veined. Petals 9.4–10.0 × 1.2–1.3 mm, fleshy, extended, linear-oblanceolate, acute but narrowly rounded at the extreme apex, margin entire, 3-veined. Lip 5.8–6.2 × 3.8–4.1 mm, entire, fleshy, slightly porrect, arched, fused to the column, obovate-pandurate, acute, margin entire, the basal margin involute, thus the lip truncate at the base, 10-veined, with the lateral veins branched; with a transverse entire callus at the base, the sides extend apically, the middle region shorter, truncate with a small hollow on each side of the mid-rib, a narrow, low rounded mid-rib running down the entire lip to the apex, with a smaller, shorter rib on each side. Column 4.0–4.8 × 1.5–2.0 mm, short, straight, terete, apex truncate, with a small rounded wing on each lower side, with a pair of oblique long thickenings inside that close the aperture to the nectary; clinandriumhood prominent, dentate, with a protuberant mid-lobe, separated on each side by a deep cleft, covering the anther; stigma ventral, concave, covered by a viscous substance; rostellum apical, laminar; nectary penetrating four-fifths the ovary, constricted at the height of the perianth, unornamented. Ovary 15.0–15.8 × 2.2–2.3 mm, straight, terete, slightly inflated ventrally nearly throughout, unornamented. Anther 1.1 × 0.9 mm, dorsal, obovate, apex truncate somewhat concave, glandular-papillose, 4-celled; pollinarium 1 mm long, formed by 4 pollinia, yellow, sub-equal, obovate, laterally compressed, wax-like, caudicles granulose; viscidium semi-liquid. Capsule not seen.

Distribution and habitat: —The two known populations of this species are found in remnant forests disturbed by human activities on introduced trees (El Carmen-Los Amarillos) in El Oro province ( Fig. 22 ). Epidendrum viridiochraceum grows as an epiphyte on branches of species of Citrus Linnaeus (1753: 782) and Ficus Linnaeus (1753: 1059) and Theobroma cacao Linnaeus (1753: 782) at 230–1100 m in elevation.

Phenology: —In cultivation E. viridi-ochraceum flowered between April and July.

Etymology: —The specific epithet derived from the Latin viridi- “green” and ochraceus “ochre”, in reference to the green-colored column and callus and ochre-colored tepals.

Additional material examined:— ECUADOR. El Oro: Cantón Piñas, Piedras, vía El Carmen-La Bocana , 230 m, 26 May 2014, Zambrano B . s.n. ( QCNE). Cantón Piñas, parroquia Capiro, sector Los Amarillos , 1100 m, 28 October 2019, Zambrano B . 2435 (QCNE).

Comments: — Epidendrum viridi-ochraceum belongs to the Spathiger group, and is distinguished by the narrowly oblong, non-bilobed, mucronate leaves, ochre-orange flowers with green column, a sweet nocturnal odor, petals linearoblanceolate, 3-veined and the lip obovate-pandurate, acute, with an entire callus and three fleshy, parallel, low ribs. The most similar species is the Mesoamerican E. cardiophorum which can be distinguished by the larger plants (35 cm vs. 15 cm tall), bilobed leaves (vs. entire), green flowers (vs. ochre-orange), ovate-elliptic dorsal sepal (vs. oblonglanceolate), 5-veined petals (vs. 3-veined), and an ovate-cordiform lip (vs. obovate-pandurate) ( Jiménez & Hágsater 2010). Epidendrum angustisegmentum ( Williams 1946: 371–372) Hágsater (1999: pl. 308), from Costa Rica and Panama, is also similar, but it can be distinguished by the elliptic leaves (vs. narrowly oblong), the yellow to yellowgreen flowers (vs. ochre-orange), ovate dorsal sepal (vs. oblong-lanceolate), and an ovate, bicallose lip (vs. obovatepandurate, with an entire callus).

The Colombian Epidendrum beatricis Hágsater & Uribe (2019 : pl. 1707), differs in the leaves apically bilobed (vs. entire), flowers without fragrance (vs. producing a sweet nocturnal odor), 5-veined dorsal sepal (vs. 8-veined), linearoblong petals (vs. linear-oblanceolate), and a sub-rectangular-ovoid, bicallose lip (vs. obovate-pandurate, with an entire callus). Epidendrum rigidum Jacquin (1760: 29) , from the Antilles and Northern South America, differs in having green flowers (vs. ochre-orange), a narrowly obovate dorsal sepal (vs. oblong-lanceolate), narrowly oblanceolate petals (vs. linear-oblanceolate), and an ovate, bicallose lip (vs. obovate-pandurate, with transverse entire callus). Finally, Epidendrum viridium , also described herein, differs in the narrowly oblong-elliptic, emarginate leaves (vs. narrowly oblong, obtuse-mucronate), flowers green turning yellow-green when old, producing a camphorated-lemon odor (vs. ochre-orange, with a sweet odor), oblong-ovate, obtuse dorsal sepal (vs. oblong-elliptic, acute), oblong, obtuse petals (vs. linear-oblanceolate, slightly acute), and an oblong-obovate, rounded lip with short parallel ribs not running the entire length of the lip (vs. obovate-pandurate, acute, with three fleshy, low ribs, the mid-rib running down the entire lip to the apex).

Figures

FIGURE 20. Epidendrum viridi-ochraceum Zambrano, Hágsater & Solano. A. Habit. B. Flower, frontal view. C. Perianth dissection. D. Ovary and column, lateral view. E. Detail of the column, lateral and ventral view. Drawn by B.J. Zambrano based on the plant that served as type.

FIGURE 21. Epidendrum viridi-ochraceum Zambrano, Hágsater & Solano. A. Habit. B. Apex of the leaf. C. Flower, frontal view. D. Perianth dissection. E. Ovary and column, lateral view. F. Detail of the column, lateral and ventral view. G. Anther cap and pollinarium. Plate by B.J. Zambrano based on the plant that served as type.

FIGURE 22. Known locality of Epidendrum viridi-ochraceum in southwestern Ecuador. Map by B.J. Zambrano.