Epidendrum campos-portoi Barberena, 2016

Barberena, Felipe Fajardo V. A. & Gonzaga, Diego Rafael, 2016, A new species of Epidendrum (Epidendroideae; Orchidaceae) from the Brazilian Atlantic Forest, Phytotaxa 284 (3), pp. 225-230 : 227-229

Epidendrum campos-portoi Barberena , sp. nov. ( Figs. 1 , 2 )

Type: — BRAZIL. Rio de Janeiro: Itatiaia [Resende], Região de Visconde de Mauá/Maromba, Trilha da Travessia Rancho Caído, Parque Nacional do Itatiaia, elev. 1,840 m, 12 May 2016, D. R. Gonzaga et al. 678 (Holotype RB!, isotype ALCB!).

Similar to Epidendrum subpurum Reichenbach (1854: 21) , but differs in the thinner, cylindrical stems (0.1–0.15 cm vs. 0.4–0.8 cm wide; vs. thinly fusiform), not thickened (vs. thickened without forming an obvious pseudobulb); racemose inflorescence (vs. a double-raceme inflorescence); green flowers (vs. white or yellow-whitish flowers).

Epiphytic, erect, cespitose herb. Roots 13–16 × 0.15–0.2 cm, cylindrical, glabrous. Rhizomes inconspicuous. Stems 11.5–27 × 0.1–0.15 cm, green, not thickened, unbranched, cylindrical, covered with congested sheaths. Leaves 4–8.3 × 0.2–0.4 cm, green, 3–6, alternate, distichous, distributed along apical half of stems, subchartaceous, suberect, plane, linear, apex acuminate, margin entire. Inflorescence 2.8–4 cm long, terminal, in simple or compound raceme; spathaceous bract ca. 1.5 cm long, imbricate. Floral bracts 0.25–0.4 × 0.05–0.1 mm, shorter than pedicel+ovary, adpressed, linear, apex acuminate. Flowers 3–4, entirely green, resupinate, simultaneous; pedicel+ovary 0.9–1.1 cm long; dorsal sepal ca. 0.9 × 0.1 mm, oblong-linear, slightly convex, 3-veined, apex acute, margin entire, lateral sepals 0.7–0.8 × 0.2–0.25 cm, free, oblanceolate, 3-veined, falcate, slightly concave, apex apiculate, margin entire; petals ca. 0.8 × 0.05 cm, linear, 1-veined, apex slightly acute to rounded, margin entire; lip adnate to column, deeply trilobed, striated, slightly revolute, base of disk with three basal, laminar calli ca. 0.15 cm long, lateral lobes 0.25–0.3 × ca. 0.2 cm, suborbicular, apex rounded, margin erose, central lobe 0.25–0.35 × 0.3–0.4 cm, subquadrangular, apex emarginate, margin erose, column ca. 0.5 cm long, adnate to lip up to its apex, subcylindrical, slightly curved; anther apical, subquadrangular, clinandrium entire; pollinia 0.45–0.5 × ca. 0.2 cm, obovate, 4, slightly unequal, laterally flattened. Capsules not seen.

Etymology: —The specific epithet honors the noted botanist Paulo Campos Porto, who studied the orchids of the PARNA Itatiaia during the early 20 th century and developed a list of orchid species from the area.

Distribution and habitat: —Endemic to Rio de Janeiro state, in Brazil ( Fig. 3 ). Epidendrum campos-portoi occurs in Upper-Montane Ombrophilous Forest in PARNA Itatiaia, above 1,840 m elevation, where it grows as epiphyte in the basal strata of the phorophytes (0–2 m high). Although the species is so far known only from the type locality, its occurrence in the bordering states of São Paulo and Minas Gerais can be expected, since the Mantiqueira Range extends through the three states, forming a continuous forest with high elevations (mostly above 1,000 m).

Phenology: — Epidendrum campos-portoi was observed with flowers in May. We presume that it also blooms in the field in June, since floral buds were observed in the preceding month.

Conservation: —Only three individuals were found in an area that is difficult to access in PARNA Itatiaia. The specimens were found near each other (<5 m) on two phorophytes. The population is probably small (possibly fewer than 50 individuals), but an exhaustive search would necessary to adequately estimate the population size and assess the conservation status of the species. However large and extensive the population may be, illegal collection of plants and the danger of fire are the main concerns for the conservation of the species.

Affinities:— Epidendrum campos-portoi better fits with the Epidendrum amblostomoides Hoehne (1938: 18) group, which is characterized by the caespitose habit, cylindrical to thinly fusiform stems, narrow leaves distributed along the apical half of the stems, lack of a spathaceous bract, often a double-raceme inflorescence, greenish, yellow, or white flowers, and usually trilobed lip ( Carnevali & Romero 1992, Hágsater et al. 2004, 2006). Epidendrum campos-portoi is morphologically similar to E. subpurum . Both species are relatively small (≤ 30 cm long), have linear leaves, falcate lateral sepals, linear petals, deeply trilobed lip, orbicular lateral lobes, central lobe with emarginate apex, and three laminar calli on the base of the disk, but E. campos-portoi is easily distinguished by the following characters: thinner (0.1–0.15 cm wide), cylindrical stems, not thickened, racemose inflorescence, and green flowers ( Figs. 1 and 2 ) (vs. thicker, 0.4–0.8 cm wide, thinly fusiform stems, thickened without forming obvious pseudobulbs; a double-raceme inflorescence; white or yellow-whitish flowers). Epidendrum supurum is known from Trinidad and Tobago, Venezuela, Ecuador, and Brazil ( Govaerts et al. 2016). In Brazil, Barros et al. (2015) have cited the occurence of E. subpurum in Rio de Janeiro and Goiás state, but we cannot validate the occurrence of the species in Rio de Janeiro because herbarium collections coming from this state were not found. Therefore, the species is so far restricted to Goiás, occurring only in Cerrado phytogeographic domain.

Epidendrum campos-portoi is also morphologically similar to Epidendrum amblostomoides , but differs in lateral lobes with erose margins and central lobe slightly longer than lateral lobes (vs. lateral lobes with entire or indistinctly eroded margins; central lobe noticeably shorter than lateral lobes), in addition to the same characteristics used to differ E. subpurum from E. campos-portoi . Epidendrum amblostomoides is endemic to Brazil, occurring in the Amazon and Cerrado, at elevations below 1,000 m ( Barros et al. 2015).

Studies on Orchidaceae in Itatiaia massif were started by Ule (1895). Since then, important results expanded the knowledge of the orchidoflora in the area, especially the description of 16 new species, including E. campos-portoi . In PARNA Itatiaia, Epidendrum campos-portoi could be confused when sterile with Epidendrum mantiqueiranum Porto & Brade (1840: 38) and Epidendrum chlorinum Barbosa Rodrigues (1881: 139) , sympatric species in the area above 1,840 m elevation, but differs mainly in the deeply trilobed lip with three laminar calli on the disk.

Figures

FIGURE 1. Epidendrum campos-portoi Barberena.A. Habit. B. Flower: diagonal view. C. Flower: frontal view. D. Flower: lateral view. E–F. Flower dissected. G. Column: lateral view. H. Anther: dorsal view. I. Anther: ventral view. J. Pollinia. Illustrated by Maria Alice Rezende based on D.R. Gonzaga et al. 678 (RB).

FIGURE 2. Epidendrum campos-portoi Barberena. A. Floriferous branch. B. Flowers (lateral and back view). Photograph by D.R. Gonzaga.

FIGURE 3. Distribution map of Epidendrum campos-portoi Barberena (black hexagon), highlighting the Parque Nacional do Itatiaia and states limits.