Columnea longipedicellata M.Amaya, Clavijo & O.H.Marín, 2015

Amaya-Márquez, Marisol, Clavijo, Laura & Marín-Gómez, Oscar Humberto, 2015, Columnea longipedicellata, a new species of Gesneriaceae from Colombia, Phytotaxa 217 (3), pp. 273-278 : 273-276

Columnea longipedicellata M.Amaya, Clavijo & O.H.Marín , sp. nov. ( Figs. 1 & 2 )

Columnea longipedicellata differs from C. segregata by having longer (15–19+ cm) pedicels and leaves homogenously green on the abaxial side.

Type:— COLOMBIA. Antioquia: Municipio Urrao, corregimiento La Encarnación, vereda Calles, National Natural Park Las Orquídeas, road Calles–Encarnación, after the confluence of the rivers Polo and Calle, place La Quiebra, 6°30’31’’N, 76°14’ W, 1600–1850 m, 31 January to 2 February 2011, P. Pedraza -Peñaloza, J. Betancur, M. F. González, G. Giraldo, F. Gómez, A. Duque & J. Serna 2139 (holotype COL!, isotypes JAUM! NY!).

Suffrutescent climber, 0.6–3 m tall. Stems terete, 2–4 mm diam., epidermis green, apically pubescent, basally glabrous; internodes 2–5 cm long, nodes with a pair of deep purple glands at the base of each petiole. Leaves opposite, strongly anisophyllous in a pair, papyraceous; larger leaf of pair with short petiole, 1–3 mm long, sericeous (5–7-celled-trichomes), blade asymmetrical, narrow oblong to falcate, 14.5–19 × 1.8–3.5 cm, base oblique, apex long acuminate, margin entire, upper surface green and glabrous, lower surface pale green and pubescent, pubescence more dense on the veins, 6 veins on the larger side of the blade; smaller leaf stipule-like, sessile, lanceolate, 9–12 × 0.8–1 mm. Inflorescence reduced to a single axillary flower; 2 inconspicuous bracts, 2 × 0.5 mm, deciduous. Flower pedicellate, pedicel 15.5–22 cm long, epidermis green to red-purple, indument red and sericeous (5–7-celled-trichomes). Calyx deep purple and reddish, sepals nearly free, unequal, lanceolate, 1.4–1.8 × 0.2–0.6 cm, adaxially pubescent, abaxially sericeous with 10-celled-trichomes that are translucent at base and center, and reddish at apex and periphery; margin pectinate with 9 segments per side. Corolla yellow, oblique to almost perpendicular relative to the calyx, outside pubescent, 3–4-celled-trichomes, inside pubescent; tube sigmoid, 21 mm long, 8 mm wide near apex (widest) to 4 mm wide near based (most constricted), base dorsally gibbous, gibbosity 4 × 7 mm; limb subactinomorphic, 9 mm wide; lobes patent, obtuse, margin erose, subequal, 2–3 × 2–4 mm. Androecium of 4 stamens, didynamous; filaments 1.3 cm long, laminar, basally pubescent; connate at base for 7 mm of their length forming a folded dorsally open blade; anther subquadrate 2 × 1.5 mm. Gynoecium with ovary oblong, 6 × 3 mm, pubescent; style 1.2 cm long, pubescent; stigma bilobed. Nectary of two connate bidentate glands, 1.4 × 0.9 mm. Fruit green, ovoid berry, 0.9 × 0.5 cm. Seeds amber, obliquely striated, 1.2 × 0.4 mm.

Distribution:— Columnea longipedicellata is endemic to Colombia, only known from the western slopes of the Cordillera Occidental, in the departments of Antioquia and Chocó. This species has been collected in the Premontane Rain forests (bp-PM) ( Holdridge 1978) at elevations from 1600–1850 m. It is a rare species that grows in the interior of well-conserved forests.

Phenology:—Flowers recorded in January, February, and April. Specimens with immature fruits have been recorded in May.

Etymology:—Named for the elongate pedicel.

Discussion: — Columnea longipedicellata is morphologically similar to C. grata Morton (1938: 1164) , C. sanguinolenta (Klotzsch ex Oersted 1858: 49) Hanstein (1865: 389) , and C. segregata Morley (1973: 459) . These species share the following characteristics: pronounced anisophylly with the larger leaf of each pair adaxially glabrous, 6 (5–7) veins per side, inflorescence reduced to a single axillary flower, bracts reduced in size (2–9 mm long) sometimes deciduous, flower pedicellate, calyx lobes or sepals fimbriate or laciniate, corolla red or yellow. Columnea longipedicellata is distinguished from the above mentioned species by a longer pedicel (15.5–22 cm vs. 2–13 cm long), and the abaxial side of the larger leaf in each pair uniformly green without red or purple spots.

Additionally, Columnea longipedicellata can be differentiated from: a) C. grata by the small yellow corollas 2–2.1 cm long (vs. red corollas 2.9–4 cm long), and the larger leaf of each node narrow oblong to falcate, 14.5–19 × 1.8–3.5 cm (vs. elliptic to oblanceolate 4.6–11 × 1.4–3.9 cm); b) C. sanguinolenta by the small yellow corollas 2.1 cm long (vs. red corollas of 3–5 cm long); and c) C. segregata by the larger leaf in each node with the margin entire (vs. serrulate), the corolla uniformly yellow (vs. yellow with maroon or deep purple spots on the corolla lobes), and the corolla oblique to almost perpendicular, relative to the calyx ( Fig. 2 ) (vs. corolla erect in the calyx).

Recent phylogenetic analyses of the genus Columnea have revealed seven monophyletic clades named A–G ( Smith et al. 2013b), and currently provides the foundation for a revised sectional classification of the genus that includes the description of a new section ( Schulte et al. 2014). Columnea longipedicellata was not included in those analyses; therefore its position in the phylogeny is unknown. Columnea segregata (one of the morphologically similar species to C. longipedicellata ) was included in the phylogeny but it was not recovered within any of the resolved clades. The inclusion of the species C. longipedicellata , C. grata , C. sanguinolenta , and C. segregata will be important in resolving their position and phylogenetic relationships within the genus Columnea and in understanding their biogeographic history. Particularly, given that C. longipedicellata is the only South American species in this group, while the other species are distributed in Central America. Additionally, ecological and phylogenetic studies on the evolution of the elongate pedicel observed in C. longipedicellata will provide an understanding of its evolutionary role in animal-plant interactions.

Additional specimens examined (paratypes):— COLOMBIA. Antioquia. Municipio de Urrao: Parque Nacional Natural Las Orquídeas, sector Calles, camino hacia la Virgen, 1800–2200 m, 15 April 2011, J. Betancur, P. Pedraza - Peñaloza, J. M. Vélez-Puerta, A. Orejuela & A. Duque 15236 ( COL!). Chocó. Municipio de San José del Palmar : vereda San Antonio, Escuela San Antonio, 4º52’N, 76º13’W, 1750 m, 15 May 2011, O. H. Marín-Gómez & D. A. Gómez-Hoyos 121 ( COL!) ; road between Alto Galápagos and San José del Palmar, 4°51’35.8’’N, 76°13’25.7’’W, 22 May 2013, J. F. Smith, O. H. Marín-Gómez & J. Arango Bermúdez 10869 ( COL!) .

Figures

FIGURE 1. Columnea longipedicellata. A. Habit. B. Detail of the indumentum on the abaxial side of the larger leaf. C. Flower. D. Corolla dissected to show the androecium. E. Pistil. F. Fruit with persistent nectary glands and calyx. (A–F from holotype, P. Pedraza–Peñaloza et al. 2139 (COL!)); Illustration by Marcela Morales).

FIGURE 2. Columnea longipedicellata. A. Plant in its natural habitat. B. Flower hanging from the elongate pedicel. C. Ventral view of the vegetative shoot showing the pronounced anisophylly at each node and the solitary axillary flower. D. Front view of the corolla limb. E. Lateral view of the flower (Photos AC: Oscar Humberto Marín Gómez, BDE: María Fernanda González Giraldo).