Markea huilensis A. Orejuela & J. M. Vélez, 2014

Orejuela, Andrés, Orozco, Clara Inés & Barboza, Gloria, 2014, Three new species of Markea (Solanaceae, Juanulloeae) from Colombia, Phytotaxa 167 (2), pp. 151-165 : 156-160

Markea huilensis A. Orejuela & J. M. Vélez , spec. nov. ( Fig. 3 , 6 , 7 ).

Type:― COLOMBIA. Huila: Municipio de La Plata , vereda La María, Finca Meremberg, sitio Agua Bonita, 2287 m, 02°12’13.1” N, 76°06’33.8” W, 5 August 2010, A . Orejuela & J. M. Vélez-Puerta 112 (holotype COL!; isotypes COL!, MO!) .

Markea huilensis is similar to Markea lopezii Hunz. from which it differs by its tubular-campanulate yellowishgreen corolla with conspicuous purple veins, anthers completely exerted, 2-locular fruit with leathery exocarp, not translucent and black when dry.

Epiphytic or hemi-epiphytic vine adhering to the trees by adventitious roots. Stem terete in fresh material, irregularly angulate when dry, the indument of simple trichomes, 0.2-1.8 mm long, uniseriate, (2) 4 to 7 (11) cells, hyaline, ochre to brown, with deciduous apex and a multicellular usually persistent base conferring the surface a tuberculate appearance, the internodes in young branches (1.5–) 2.1–4.5 (–5.2) cm long, densely hirsute, the adult branches are congested with apparent whorled leaf arrangements, becoming glabrescent as they age, and bearing broad circular foliar scars left by the petiole insertion and by the dryness of the branches, the bark pale brown. Leaves subopposed or alternate on young branches, apparently whorled on adult branches and crowded towards the tip; petiole pale green when fresh, 0.4–3.8 cm long, conspicuously articulate, densely hirsute; blade elliptic to broadly elliptic, 9.0–16.7 × 4.6–11.7 cm, rarely asymmetric, membranaceous, sparsely pubescent both abaxially and adaxially, with simple trichomes, 0.3–2 mm long, uniseriate, with 4 to 9 cells, hyaline in fresh, brown to dark olive when dry, the base asymmetric, cuneate or obtuse, the apex usually acuminate, 7–9 mm long, mucronate, the margin entire, undulate, the secondary veins 4 to 6 pairs, slightly raised abaxially, reticulum inconspicuous both adaxially and abaxially. Inflorescence in monochasial cymes, simple, sometimes branched, at sub-axillary position, 24–53 cm long, longpedunculate, pendulous, 2 to 7 flowers, bracteate, the surface tuberculate and densely hirsute with trichomes as on the stems; peduncle 8.5–19 cm long; bracts foliaceous and linear ca. 5.6 × 1.5 cm, the floral buds ellipsoid, ca. 10.5 × 2.5 cm, calyx and corolla aestivation valvate and cochlear respectively. Flowers pedicellate; pedicel 1.5–2 mm long, conic, 5-ribbed, distally thickened. Calyx 5-lobed, ca. 3.3 × 1.5 cm, dark green with purple margins in fresh material, adaxially reticulate, abaxially pubescent, the trichomes simple multicellular, uniseriate, 4 to 7 cells, hyaline to brown, the tube 5–7 mm long, the lobes lanceolate, 2.7–5.2 × 1.3–1.5 cm, the apex largely acuminate, acumen 6–9 mm long. Corolla 5-lobed, tubular-campanulate, 8.5–10 × ca. 4.8 cm, yellowish green, strongly reticulate both abaxially and adaxially, exhibiting violaceous veins in fresh material, scarcely pubescent, trichomes similar to those of the calyx, the tube 6.2–6.7 cm long, differentiated into a narrow base ca. 20 × 8–10 mm and a wide distal portion 4.2–4.6 x ca. 5 cm, the lobes oblong, revolute, with the apex obtuse, reflexed during anthesis, 2.3–3.3 × 1.6–1.7 cm. Stamens 5, exerted, 6.1–6.9 cm, the filaments 4.7–5 cm long, adnate at ca. 2 cm from the base of the corolla, with hyaline dense indument of simple, uniseriate trichomes at the insertion point, the anthers basifixed 14–19 × 1.3–1.5 mm, not connivent. Ovary conic, 7 × 3.5 mm, light yellow, 2-carpelar, 2-locular, glabrous, the disc nectariferous well developed and lobed, light green in fresh material. Style 7.3–8 cm long, cream, glabrous. Stigma 2-lobed, clavate, glabrous. Fruit a berry, ovoid, 4.2 × 2.5 cm, dark green when fresh, exocarp 2–2.8 mm, thick when fresh, coriaceous, black when dry, the persistent calyx partially covering the fruit, 4–5 × 2.3 cm. Seeds numerous, subreniform, 2.6–3.0 × 1.2–1.4 mm, ochre in fresh material, dark brown when dry, the testa reticulate; embryo slightly curved, 2.5 × 0.5 mm, cotyledons shorter than, and as wide as the rest of the embryo, with a slight constriction at the junction point, endosperm abundant.

Etymology: —The specific name refers to the department of Huila, where the known collected samples of this new species come from.

Habitat and distribution:— Markea huilensis is known only in the department of Huila, southwestern Colombia. This species is found in preserved or partially altered forest at 2200–2300 m .

Phenology: —Flowering and fruiting take place from July to August and December to January.

Conservation status:— Markea huilensis is known from four collections of two localities in the department of Huila, Colombia, with an approximate distance of 80 km in between. Markea huilensis is proposed here as an endangered species ( EN), conforming to criterion B 1ab [i, iii] of the IUCN (2012), as the area where it is found is approximately 300 km 2, and also because of the highly fragmented conditions of the forest relicts surrounding this area. Apart from this, the places where it has been collected are not under any governmental protection program.

Additional material examined:— COLOMBIA. Huila: municipio La Plata, vereda Agua Bonita, Finca Meremberg , 1200–1300 m (the real altitude of this locality is 2200–2300 m; the discrepancy is probably due to a typing mistake on the label of this specimen), 21 July 1975, Díaz-Piedrahita et al. 793 ( COL) ; Carretera Popayán-La Plata, km 100, Reserva forestal de Fauna y Flora Merenberg , 2300 m, 12 December 1982, Murcia 09 ( COL) ; Municipio San Agustín, vereda La Castellana, reserva privada Los Yalcones , interfluvio quebrada El Palmar-río Balseros , sitio El Palmar , 2400–2600 m, 1°47´44” N, 76°21´5” W, 15–20 August 2005, Mendoza & Robles 16548 ( FMB) .

Discussion:— Markea huilensis is sympatric with M. sturmii , but, they are morphologically very different ( Fig. 5B , 6,7), the size of the corolla in M. huilensis is longer than 4 cm (see the key), whereas in M. sturmii is up to 3 cm long. Markea huilensis is morphologically and phylogenetically (Orejuela et al. in prep.) related to Markea epifita S. Knapp (1998: 155) and Markea lopezii Hunz. (1985: 9) . These taxa form a group of species with elongated and pendulous inflorescence with nodose and tuberculate axes, bearing few flowers, with showy corollas (9-12 cm long). These species also share the apparently verticillate arrangement of the adult leaves, the membranaceus leaf blade, with simple and uniseriate trichomes persistent on both surfaces. The pedicels are distally winged and the calyx has membranaceous and well developed lobes with largely acuminate apexes ( Fig. 4F , 6 , 7 ).

Markea huilensis is differentiated from M. epifita and M. lopezii because it is a more robust and densely hairy plant. The corolla in M. huilensis is tubular-campanulate while in M. lopezii and M. epifita is tubular funnelform ( Fig.4F , 6 , 7 ). In M. huilensis the corolla is yellowish green, with purple veins both abaxially and adaxially, instead in M. lopezii the corolla is orange with purple tinges at the base of the corolla adaxially, while in M. epifita the corolla is cream or green with purple lines or tinges in the throat and in the lobes.

The anthers in M. huilensis are completely exerted while in M. lopezii they are partially included and in M. epifita completely included. The fruit in M. huilensis with leathery exocarp, not translucent and black when dry, is 2- locular, while in M. lopezii the fruit with membranaceous exocarp, light yellow and translucent when dry is visually 4-locular even though it comes from a 2-locular ovary, probably due to secondary formation of placental septa during fruit development. The fruit in M. epifita is not yet known. Finally, light microscope analysis of the pollen grains of M. huilensis indicates that this new species lacks spinal supratectal process observed by Persson et al. (1994) in M. lopezii .

Figures

FIGURE 3. Distribution map for Markea hunzikeri (circles), Markea huilensis (stars) and Markea purpurea (squares). Cordilleras in Colombia (gray color).

FIGURE 4. Markea species with corollas longer than 4 cm.A. M. antioquensis. B. M. coccinea. C. M. formicarum. D. M. fosbergii. E. M. longiflora. F. M. lopezii. G. M. pilosa. H. M. plowmanii. I. M. sessiliflora. (Photographs A by Julio Betancur; B, C by Robin Foster; D by Rocío Deanna; E by Hervé Galliffet; F by Eduardo Calderón; G by Andrés Orejuela; H by Antonio Peña; I by Günter Gerlach).

FIGURE 5. Markea species with corollas up to 3 cm long. A. M. panamensis. B. M. sturmii. C. M. ulei. (Photographs. A, B by Andrés Orejuela; C. by María Fernanda González).

FIGURE 6. Markea huilensis. A. Floriferous branch. B. Indument on the leaf blade. C. Indument on young stems. D. Leaves arrangement. E. Flower bud. F. Flower in anthesis. G. Stamens. H. Gynoecium. I. Fruit with sepals removed. J. Fruit in cross section. K. Seed. L. Embryo. Based on A. Orejuela & J. M. Vélez-Puerta 112, type collection (COL); Murcia 9 (COL); Diaz-Piedrahita et al.793 (COL). Drawing by Marcela Morales.

FIGURE 7. Markea huilensis. A. Floriferous branch. B. Detail of the indument C. Flower bud. D. Open corolla. E. Immature fruit. F. Developed fruit (holotype A. Orejuela & J. M. Vélez-Puerta 112. Photograph by Andrés Orejuela).