Lepanthes florenciana J.S.Moreno & D.Hoyos, 2022

Moreno, Juan Sebastián, Hoyos, David, Rincón, Milton, Sierra-Ariza, Mario, Escalante, Maria Fernanda Valencia & Morales, Nicolás Gutiérrez, 2022, Lepanthes florenciana (Orchidaceae: Pleurothallidinae), a new species from the Eastern Andes of Colombia, Phytotaxa 559 (1), pp. 55-63 : 56-62

Lepanthes florenciana J.S.Moreno & D.Hoyos , sp. nov. ( Figures 2 , 3 , 6 , 7A )

Type:— COLOMBIA. Caquetá: Municipio de Florencia, vía Florencia – Neiva, entre el puente Mirador y Viaducto Losada , 1698 m, 13 January 2022, D. Hoyos , O. López & A. Fonseca 945 (holotype: COAH!, isotype: HUAZ!) .

Lepanthes florenciana is similar to Lepanthes niphas Luer & Escobar (1991: 68) , but easily distinguished by the presence of petals transversely trilobed with the lobes dolabriform (vs. transversely bilobed with the lobes narrowly triangular); lunate lip blades (vs. semi-orbicular) and an oblong pubescent appendix (vs. with a minute apiculum in the sinus).

Description:— Plant small in size, epiphytic, caespitose, 3.7–5.25 cm tall; roots, slender, flexuous, filiform, up to 0,6 mm in diameter. Ramicauls, slender, erect 1.7–3.4 cm long, enclosed by 6–8 acuminate, ribbed and short-ciliate lepanthiform sheaths, with a dilated and ciliate ostia. Leaves occasionally suffused with purple on the abaxial surface, erect, broadly elliptic 1.25–1.82 × 0.82–1.03 cm, the apex contracted into an abaxial small apiculum in the middle, the base cuneate, contracted into a petiole of 0.97–1.39 mm long. Inflorescence 1–2 per ramicaul, a congested raceme, borne near the apex of the ramicaul at the abaxial surface of the leaf, almost as long as the leaf, 0.82–1.45 cm long including the filiform, terete peduncle, 3.34–4.59 cm long, carrying 9–25, successively, distichous flowers; floral bracts conical, acuminate, 1.02–1.43 mm long; pedicels terete, more or less arcuate, 1.13–1.90 mm. Ovary terete, costate, 1.37–3.02 mm long. Flowers have two color variation within the same population, light green and yellow, the type species with homogeneous light green, sepals translucent white or primrose to strong translucent pale yellow; petals and lip white to whitish green or yellow to lemon, bright yellow with a hint of green. Dorsal sepal ovate-lanceolate, slightly convex, acute, 3-veined, 3.70–5.51 × 1.70–2.21 mm, connate to the lateral sepals for 0.67–0.97 mm. Lateral sepals, ovatelanceolate, oblique, acute, 2-veined, 3.68–5.72 × 1.57–1.91 mm, connate for 0.99–1.21 mm long. Petals transversally trilobed, microscopically pubescent, convex, 1-veined, 0.64–0.81 × 2.11–2.46 mm; the upper and lower dolabriform; the midlobe triangular. Lip, bilaminate, the blades lunate, embracing the column the base rounded, the apex sub-acute, repand, 0.98–1.63 × 0.37–0.55 mm, supported by cuneate connectives, the body broad, adnate between the outer and middle thirds to the column, the sinus rounded, with an oblong, pubescent appendix. Column terete, 0.83–1.89 mm long, the anther dorsal and stigma ventral. Anther cap cordate, cucullate, 0.25 mm wide. Pollinia 2, yellow, pyriform, obovoid, 0,32 mm long. Fruits not seen.

Distribution and Ecology:— Lepanthes florenciana growths at mid elevation in the Eastern slope of the Andes mountains ( Figure 4 ). Despite the height of the locality in which this species is found, it may have affinities with the Amazon. It can be explained because the environmental changes have facilitated dispersal of the Amazon towards the Andes, process known as barrier displacement ( Musher et al. 2019). The highest amounts of precipitations are recorded in the Eastern or Amazon slope ( Ruiz-Hernández et al. 2021). Thus, in the Northern Andes, the outer sides of the Eastern and Western Cordilleras, floristic diversity decreases from the base upwards as a function of precipitation and temperature, for this reason, mentioned slopes are more diverse than the slopes towards the relatively dry inter-Andean valleys ( Van der Hammen 2000). The new species was found in a very wet premontane forest, in a remnant of secondary forest by the side of the road. This discovery occurred during the X Colombian Congress of Botany ( Trujillo-Trujillo et al. 2020), when a team of botanical researchers carried out an approach to the flora of the area ( Figure 5 ).

In the same population two color variation of white and yellow were recorded ( Figure 6 ), with a dominance of the white-flowered individuals within the population. This unique population was recorded at the base of a trunk of Cupania scrobiculata Richard (1792: 109) (Sapindaceae) , growing less than one meter above the ground. The new species was found growing next to Lepanthes agglutinata Luer (1983: 327) , Marcgravia sp. Linnaeus (1753: 503) ( Marcgraviaceae ), Philodendron sp. Schott (1829: 780) ( Araceae ) and Serpocaulon fraxinifolium ( Jacquin 1789: 187) A.R. Sm. in Smith et al. (2006: 928). ( Polypodiaceae ). No additional populations of Lepanthes florenciana were found in posterior expeditions to this area.

Flowers have been found in January, June and August, but probably flowering all year long based on the observation of the long lasting successive inflorescences.

Etymology:— Lepanthes florenciana is named after the Municipality of Florencia located in the department of Caquetá, where the new species was found.

Additional material examined (paratypes): — COLOMBIA. Caquetá: Municipio de Florencia , borde de carretera que conduce al Huila, 1698 m, N. Gutierrez, H. Mendoza, F. Limón, J. S. Moreno, S. Guzmán, E. Domínguez, C. Betancourt, M. Rincón, M.F. Valencia & M. Sierra 151 (TOLI!); Vía Florencia – Neiva, entre el puente Mirador y Viaducto Losada, 1698 m, 13 June 2020, D. Hoyos & M. Cuellar 326 (CUVC!) .

Taxonomic Discussion: — Lepanthes florenciana may be part of an informal group of species proposed by Moreno et al. (2017), with large and protruding column and sepals ovate-lanceolate to triangular. The most similar species to Lepanthes florenciana is the Colombian endemic Lepanthes niphas ( Figure 7B ), subsection Breves ( Luer 1993: 442) Luer (1996: 7), found in Antioquia and Risaralda departments ( Luer & Thoerle 2012). Both species share similar small white crystalline flowers, but Lepanthes florenciana can be recognized by its leaves broadly elliptic (vs. narrowly ovate); the inflorescence as long as the leaf (vs. longer than the leaf); the lateral sepals 2-veined (vs. 1-veined); the petals transversely trilobed (vs. transversely bilobed) with the upper and lower lobe dolabriform (vs. the upper and lower lobe narrowly triangular) and a bilaminate lip with the blades lunate, the base rounded, the apex sub-acute with an oblong, pubescent appendix (vs. the blades semi-orbicular with a minute apiculum in the sinus).

Figures

FIGURE 2. Drawing of Lepanthes florenciana J.S.Moreno & D.Hoyos. A. Habit. B. Flower. C. Dissected perianth. D. Ovary, column and lip, side view. E. Lip, dorsal view (extended) and lip embracing the column. F. Anther cap and pollinia. Drawn by J.S. Moreno from the plant that served as the holotype.

FIGURE 3. Photographs of Lepanthes florenciana J.S.Moreno & D.Hoyos. A. 3/4 side of flower. B. Habit and plant in-situ. C. Side view of the flower. Photographs by J.S. Moreno (A), D. Hoyos (B) from D.Hoyos et al. 945 (COAH), and E. Dominguez (C) from N.Gutierrez et al. 151 (TOLI).

FIGURE 4. Distribution map of Lepanthes florenciana J.S.Moreno & D.Hoyos, located in Florencia, Caquetá, Colombia. Map made by D. Hoyos

FIGURE 5. Habitat of Lepanthes florenciana J.S.Moreno & D.Hoyos. A. Secondary premontane forest. B. Evidence of the forest relict from the road. C. The team that carried out the expedition to the mountains of Florencia to record a sample of plant diversity of the area. Photographs by D.Hoyos (A,B) and E. Dominguez.

FIGURE 6. Color variation within the same population of Lepanthes florenciana J.S.Moreno & D.Hoyos. A. White variation (dominant). B. Yellow variation. Photographs by M.Rincon (A) and E. Dominguez (B).

FIGURE 7. Comparison with the most similar species. A. Lepanthes florenciana J.S.Moreno & D.Hoyos from N. Gutierrez et al. 151 (TOLI). B. Lepanthes niphas Luer & R. Escobar (Photographed from the type locality). Photographs by J.S. Moreno