Lepanthes garciarovirensis E.Restrepo, H.Caro & S.M.Arango, 2024

Caro, Heidy, Arango-Carvajal, Susana, Suescún, Diego & Restrepo, Eugenio, 2024, Unhiding Colombian orchid treasures: A new Lepanthes (Orchidaceae) from the northeastern Andes in Colombia, Phytotaxa 664 (3), pp. 191-199 : 192-197

Lepanthes garciarovirensis E.Restrepo, H.Caro & S.M.Arango , sp. nov. ( Figure 1 )

Type:— COLOMBIA. Santander: García Rovira, between San Andrés and Molagavita , 6,713 09 N, -72,817522, 2626 m. 29 November 2021, H. Caro & S. Arango 59 ( holotype: JBB!) .

Lepanthes garciarovirensis is most similar to Lepanthes rabei Foldats (1968: 341) but can be easily distinguished by a combination of characteristics: plant length ca. 7.46–8.28 cm ( vs. 4.00– 6.56 cm), elliptical-lanceolate leaves turning acute, leaves attenuated light yellowish green adaxially, paler abaxially ( vs. narrowly ovate, acute, dark green adaxially, suffused with purple abaxially), and the lip blades and appendix obtusely ovate-oblong, slightly falcate at the apex with long cilia at the very tip, the appendix minute, reflexed downwards, pubescent ( vs. the blades minutely pubescent, curved, elliptical-oblong, the appendix minute, Pubescent and pedunculate).

Description:—Epiphytic herb, medium size, caespitose, erect to horizontal, 7.46–8.28 cm tall. Roots slender, flexuous, 0.95–1.01 mm in diameter. Ramicauls 4.25–5.62 cm long, enclosed by 5–8 infundibuliform lepanthiform sheaths, light brown, long ciliate along the ribs, with a ciliate, acuminate, and dilated ostia. Leaves light yellowish-green adaxially, paler abaxially, coriaceous, elliptical-lanceolate, turning acute, attenuate, triapiculate, 2.71–2.95 × 0.87–0.99 cm, the cuneate base narrowing into a petiole ca. 2.65–3.03 mm long. Inflorescence borne behind the leaf, with multi-flowered successive, congested, distichous coflorescences, one developing at a time, suberect, with slowly successive flowers, 1 opened at a time, to 2.5 cm long, including the pseudopeduncle 5–10 mm long, with 1 internode. Floral bracts membranous, conical, echinate, acute, 1.61 mm long. Ovary costate, conical, finely verrucose-papillose. Flowers with sepals light yellow, somewhat hyaline, stronger yellow along the veins, petals yellow, suffused with magenta along the internal margins of the upper lobes, lip magenta medially and suffused with yellow along the margins. Sepals carinate along the veins, plain, glabrous. Dorsal sepal ovate, the apex acuminate, narrowly acute, sometimes slightly reflexed, smooth, 3.87–4.03 × 2.51–2.53 mm, 3-veined, the midvein sulcate, connate to the lateral sepals for about 1.17 mm. Lateral sepals, ovate, oblique, the apex acuminate, acute, slightly diverging, 3.97–4.12 × 1.62–1.88 mm, connate 1.09 mm at its base, 2-veined, with short filiform-like papillae, sparsely distributed along the margins, inconspicuous. Petals transversely bilobed, microscopically puberulent, 3.32–3.08 × 0.89–0.93 mm, the lobes similar, oblong, obtuse, turning acute, ca. 1.71 mm long, then the lower lobe oblong, obtuse, turning slightly truncate to rounded, ca. 1.62 mm long. Lip bilaminate, microscopically pubescent, the blades obtusely ovate-oblong, slightly falcate at the apex and long ciliate at the very tip, 1.83 × 0.57 mm, the connectives wide, connate to the column at the base, the appendix bristle like, minute, reflexed downwards, pubescent, 0.19 mm; column stout, 1.43 mm long, the anther apical, the stigma apical; pollinarium anther cap not seen, deciduous.

Distribution and ecology:—The new species was found in the Eastern Cordillera of the Colombian Andes in the department of Santander, in the municipality San Andrés at 2626 m of elevation ( Figure 4 ). The species dwells in a relic of oak forest dominated by Quercus humboldtii Bonpland (1809: 155) and Andesanthus lepidotus (Bonpland) P.J.F. Guimarães & Michelangeli (2019: 948) . The forest is immersed in a matrix of pasturelands. The species was found growing along with Lepanthes cocculifera Luer & R. Escobar (1984: 133) and Masdevallia tubulosa Lindl. (1846: 4) . L. rabei was found in an area close to the new species in the same forest, growing over trees but also over rocks covered by moss. Lepanthes garciarovirensis has been observed flowering in the wild during October–November and July–August.

Toponymy:—In honor of the “García Rovira” province in the department of Santander of Colombia, where the type specimen of the species was found.

Taxonomic discussion:—Following Carl Luer’s morphological infrageneric system (with modifications in Luer & Thorerle 2010), there are two subgenera currently recognized: Marsipanthes (with 6 described species in Colombia) and Lepanthes (>365 species according to Karremans et al. 2023). The latter is subdivided into two sections, sect. bilabiatae, which is characterized by totally connate lateral sepals and not recorded for Colombia, and sect. Lepanthes , which is characterized by lateral sepals with no more than three veins. Within the last, subsection Lepanthes species can be distinguished by the presence of two nerves along the lateral sepals and Lepanthes subsection Breves single vein along the lateral sepals ( Luer & Thoerle 2012). We consider that L. garcia-rovirensis should be treated under subsection Lepanthes .

The new species seems to be closely related to what has historically been treated as L. rabei ( Figures 2B, 2D & 2F ). This species was synonymized by Luer & Thoerle (2012) under Lepanthes aquila-borussiae Reichenbach (1854: 22) . Luer initially noted the latter species to be likely distinct from the former, in Luer (1986), because, as it is noted in the same document, the orchid flora of the coastal mountains of Venezuela (Cordillera de la Costa) is somewhat isolated and distinct to the orchid flora from Cordillera del Mérida, and very few orchid species are shared between both. Nevertheless, the orchid flora from Cordillera del Mérida shares several Pleurothallidinae species with the adjacent eastern cordillera of Colombia (departments of Norte de Santander and Santander). Considering that the holotype of L. rabei comes from Táchira (Cordillera del Mérida) and that L. aquila- borussiae comes from an area near Caracas (Cordillera de la costa), after a careful examination of available herbarium specimens, drawings from Venezuelan Orchids Illustrated, and protologues of both species, we do prefer to treat these taxa as separate entities. This seems to be a wiser approach until L. aquila-borussiae (near the type locality) is thoroughly characterized and documented. Additionally, it can be noted that L. rabei is found in the high mountains of western Venezuela and Colombia, at elevations around 2500–3100 m ( Luer & Thoerle 2012), contrasting with the plants from the coastal mountains of Venezuela, certainly growing at lower elevations throughout their range. It is highly improbable, considering the information cited in the protologue ( Reichenbach 1854), that L. aquila- borussiae would have its type locality with similar elevations as L. rabei , which has been found growing at the same location of the new species.

The new species shares an overall similar plant and flower shape to L. rabei . It can be easily distinguished by the plant length ca. 7.46–8.28 cm ( vs. 4.00– 6.56 cm), the leaf color and shape light yellowish green adaxially, paler abaxially, elliptical-lanceolate, turning acute, attenuated ( vs. dark green adaxially, suffused with purple abaxially, narrowly ovate, acute), the sepal colors light yellow, somewhat hyaline, stronger colored along the veins ( vs. rosybrown, paler along the margins), the sepal absence of concavity and the margin spread, plain, the dorsal smooth, the tip sometimes reflexed, the laterals with inconspicuous filiform-like papillae along the margins ( vs. slightly concave, margins ciliate-denticulate, the tip not reflexed), as well as the lip blades obtusely ovate-oblong, slightly falcate at the apex and long ciliate at the very tip, the appendix reduced to a dilated sinus, reflexed downwards, pubescent ( vs. the blades minutely pubescent, curved, elliptical-oblong, the appendix pubescent, pedunculate). The new species also resembles Lepanthes eucerca Luer & Thoerle (2011: 332) ( Figure 3B ), which also grows along with L. rabei at Páramo de Jurisdicciones, in the department of Norte de Santander, in Colombia, and shares a similar plant habit and flower color with the new species. The new species can be separated from it by the sepal shape and margins. The new species has lateral sepals whose margins have short filiform-like papillae, sparse, the dorsal sepal smooth, the tip acuminate, acute, slightly diverging ( vs. sepal margins prominently denticulate, long-caudate, the dorsal sepal ovate, acute, long-acuminate, the lateral sepal ovate, oblique, diverging, acute, long-acuminate, ciliate and heavily caudate), and the appendix shape is different with ornament minute, reflexed downwards, pubescent ( vs. microscopic, setiform, bristle-like). Furthermore the new species resembles Lepanthes estrellensis Ames (1923: 30) ( Figure 3C ) from Costa Rica, which it can be easily differentiated by the leaf shape and width, elliptical-lanceolate, turning acute, up to 1 cm wide ( vs. elliptical, 2.6 cm wide), the petal lobes and their transversely bilobed arrangement, the oblong lobes, obtuse, the lower turning slightly truncate to rounded ( vs. oblong, obtuse, obliquely divaricate) and the lip blades and appendix trilobed, blades obtusely ovate-oblong, slightly falcate at the apex and long ciliate at the very tip, the minute, reflexed downwards, with a pubescent appendix ( vs. bilobed, the blades reniform, the appendix (or middle lobe) absent).

Conservation status:—Data deficient (DD). The IUCN classification is data deficient (DD), because we lack adequate distribution and population information to make an assessment (IUCN Standards and Petitions Subcommittee 2022).

Figures

FIGURE 1. Composite plate of Lepanthes garciarovirensis E.Restrepo, H.Caro & S.Arango A. Plant. B Flower, frontal view. B Close1. 2. up to the apex of the lib blades. C 1. Flower, lateral view. C 2. Close-up to the appendix D. Dissected perianth. E. Expanded lip. Prepared by Eugenio Restrepo

FIGURE 2. Species comparison between Lepanthes garciarovirensis E.Restrepo, H.Caro & S.Arango (A, C, E) and L. rabei Foldats (B, D, F) Photographs and plate by Eugenio Restrepo.

FIGURE 3. Comparison between Lepanthes garciarovirensis (A), L. aff. eucerca (B), L. estrellensis (C) & L. cuatrecasasii (D). Photographs by Eugenio Restrepo (A, D), Carlos Uribe (B) & Piotr Tuczapski (C). Prepared by Eugenio Restrepo.

FIGURE 4. Distribution map of Lepanthes garciarovirensis E.Restrepo, H.Caro & S.Arango, located in the Eastern Cordillera of the Colombian Andes in the department of Santander, in the municipalities of Molagavita and San Andrés. Prepared by Heidy Caro.