Epidendrum unchogense Ocupa et E. Santiago. A. Habit. B. Flower. C. Dissected 2022
- Dataset
- Two new species and a new record of Epidendrum (Orchidaceae) from the Carpish Montane Forest Regional Conservation Area, Peru
- Rank
- SPECIES
- Published in
- Ocupa-Horna, Luis, Jiménez, Marco M., Salinas, Julian Duarte, Ayala, Elizabeth Santiago, Hágsater, Eric (2022): Two new species and a new record of Epidendrum (Orchidaceae) from the Carpish Montane Forest Regional Conservation Area, Peru. Phytotaxa 556 (3): 269-280, DOI: 10.11646/phytotaxa.556.3.3, URL: http://dx.doi.org/10.11646/phytotaxa.556.3.3
Classification
- kingdom
- Plantae
- phylum
- Tracheophyta
- class
- Liliopsida
- order
- Asparagales
- family
- Orchidaceae
- genus
- Epidendrum
- species
- Epidendrum unchogense
conservation
Conservation status: — DD. Data deficient. This species is currently known only from the Carpish Montane Forest Regional Conservation Area, central Peru.
description
Description: — Epiphytic, descending, monopodial, branched herb. ca. 10 cm long. Roots ca. 2.5 mm in diameter, basal, white, fleshy, thin. Stems cane-like, terete, slightly sinuous to straight; primary stem ca. 4.5 – 7.9 × 0.25 – 0.39 cm, branches ca. 3.8 – 6 × 0.2 – 0.34 cm, new branches produced from a sub-apical node of a previous branch, progressively smaller, covered by non-foliar sheaths, 0.8 – 1.7 × 0.5 – 0.7 cm, infundibuliform, light brown to dark brown, with purple tones, ancipitose, striate, chartaceous. Leaves ca. 1.5 – 3.9 × 0.4 – 0.62 cm, 5 – 6 per stem, green to purplish brown, abaxially dark purplish, distributed along branches, sub-coriaceous, articulate, distichous, straight to briefly reclined, attenuate, conduplicate at base, lanceolate, channeled in central vein, margin attenuate, apex acuminate. Spathe lacking. Inflorescence ca. 5 cm long, including flowers, apical, pendulous, racemose, few-flowered; peduncle ca. 8.5 mm long, short, thin, terete; rachis ca. 3 mm long, very short. Floral bracts 3.5 – 5 × 2 – 3 mm, narrowly triangular, apex attenuate, light green or suffused with purple, membranaceous, embracing. Ovary 1.6 – 2.1 cm long, clavate, thin, 3 - furrowed, purple-greenish and widened towards apex, forming a ventral gibbose vesicle with basal portion of column. Flowers 2 – 3, simultaneous, resupinate, nutant; sepals buff-colored, with wine-red spots, petals light green, with wine-red spots below middle, lip cream tinged with wine-red spots in center, column green, wine-red at apex. Sepals free, partly spreading, slightly thickened, lanceolate, concave, 5 - veined, margin entire, extended; dorsal sepal 20 – 22 × 5.8 – 6 mm, apex acute, adaxially sub-verrucose near apex; lateral sepals 21 – 23 × 6.5 – 7 mm, apex acuminate, oblique, unequal, adaxially sub-verrucose. Petals 20 × 4.8 – 5.3 mm, free, parallel to column, slightly convex, trullate, base long-attenuate, somewhat unequal, 3 - veined, apex acute, longitudinally thickened along mid-vein, especially at half apical portion, margins slightly revolute to apical half portion. Lip 17.5 × 14 mm, attached to column, entire, narrowly ovate, deeply ovate at base, apex acute, apical half strongly recurved in natural position; bicallose; callus reniform, fleshy, wine-red, separated, forming a small cavity between them; basal sides of lip convex, microscopic, and shortly ciliated margin, giving appearance of having a bilobed apex. Column 10 × 3.5 mm, clavate, straight, widened at base, forming a ventral, gibbous vesicle with apical portion of ovary; stigma ventral, concave, covered by a viscous substance; lateral lobes of stigma thick, dark vinaceous; clinandrium-hood much reduced, margin entire. Anther 1.43 × 1.78 mm, sub-spherical, yellowish green, 4 celled. Pollinarium formed by 4 pollinia, yellow, in 2 nearly sub-equal pairs, obovoid, flattened at interfaces, caudicles attaching them in pairs, granulose; viscarium semi-liquid. Rostellum apical, slit. Nectary penetrating apical portion of pedicellate ovary, broad, smooth. Capsule not seen.
diagnosis
Epidendrum unchogense is similar to Epidendrum llatasii Hágsater, A. G. Diaz & E. Santiago (2018: pl. 1679) but differs by the lanceolate (vs. elliptic) leaves, larger flowers, the sepals 20 – 23 mm long (vs. 12 – 15 mm long), petals 20 mm long, trullate (vs. 12.5 – 15 mm long), the lip entire, narrowly ovate with acute apex (vs. lip 3 - lobed with truncate apex in the mid-lobe).
discussion
Taxonomic discussion: — Epidendrum unchogense belongs to the Soratae subgroup of the Scabrum group (Santiago & Hágsater 2007: pl. 988) which is characterized by the branching habit starting on a monopodial, primary stem, infundibuliform, rugose leaf-sheaths, lanceolate, aristate, obtuse, acute to subacute leaves, a racemose subcapitate inflorescence on a short, thin peduncle, and the bicallose lip. The new species can be easily recognized by the leaves lanceolate, acuminate apex, the laxly, three-flowered inflorescence, the sepals 20 – 23 mm long, the petals trullate in the apical half and long attenuate at the base, parallel to the column, the lip entire, narrowly ovate with the apex acute and strongly revolute and a gibbous ventral vesicle, formed between the column and the ovary. It is similar to E. llatasii Hágsater, A. G. Diaz & E. Santiago (2018: pl. 1679), described from northern Peru but recently recorded for the San Pablo de Pillao district of Huánuco (Dalström 3675, digital images, AMO!), has greenish-yellow, concolorous flowers, sepals 12 – 15 mm long, petals linear with rounded apex and the lip incipiently 3 - lobed with the lobe transversely rectangular and the apex truncate strongly revolute. Other related species such as E. carpishense Hágsater, D. Trujillo & E. Santiago (2009: pl. 1215) has 3 – 4 creamy yellow flowers, concolorous, the sepals 4.5 – 5 mm long, the petals linear-filiform and the lip reniform. The shape of the callus and revolute apices of the lip of E. unchogense are slightly reminiscent of E. labrychilum Hágsater, Edquén & E. Santiago (2019: pl. 1730) recorded from northern Peru, in San Martín Department, but that species has smaller flowers (sepals 9 mm long) and filiform petals 8 × 0.3 mm, in addition to the lip is 3 - lobed with the median lobe short and incipient (Table 2, Figure 6).
distribution
Distribution and ecology: — Epidendrum unchogense is a rare species known presently only from a small area located on the western slope of the central branch of the Andes, in Churubamba District, Huánuco Department (Figure 2). The type specimen was recorded in a small area within the Unchog Montane Forest, in the southern part of the Carpish Montane Forest Regional Conservation Area, growing as an epiphyte on branches of Miconia monzoniensis Cogniaux (1908: 140) (Melastomataceae), between 2663 – 2817 m altitude, along the trail on the way to Ñaupamarca. This species was observed flowering in March, at the beginning of the rainy season in that department.
etymology
Etymology: — The specific epithet is named in honor of the montane forest of Unchog, where this unusual Epidendrum was found.
materials_examined
Type: — PERU. Huánuco: Prov. Huánuco, Distrito Churubamba, Área de Conservación Regional Bosque Montano de Carpish, bosque de Unchog, 2817 m, 07 Mar. 2022, L. Ocupa 299 (holotype: USM-Spirit!).