Lepanthes obandoi Tobar & M.F.López., 2018

Tobar, Francisco, López, María Fernanda, Muñoz-Upegui, Dolly & Richter, Friederike, 2018, Two new species of Lepanthes (Pleurothallidinae; Orchidaceae) from Andean forest remnants in Ibarra, Ecuador, Phytotaxa 375 (3), pp. 221-228 : 224-227

Lepanthes obandoi Tobar & M.F.López. , sp. nov. ( Figs. 3A − F , 4A − C )

Type: — ECUADOR. Imbabura: Ibarra, El Sagrario, along the maintenance path of the drinking water network system of La Carbonería , 3538 m., 0035’04” N, 78°59’4” W, Jul 2016, Tobar, Monge & Obando 1983 (holotype: QCA, spirit; isotypes: HPUSECI, QCNE)

Similar to Lepanthes muscula Luer (1983: 354) but differing in the much taller plant with distinct superposed stems, oblong petals with the upper lobe slightly broader and larger than the lower one, labellum blades obliquely lanceolate, apically divergent, yellow, elongate appendix with orbicular, pubescent apex and a prominent tuft of basal white hairs.

Terrestrial or occasionally lithophytic, caespitose, prolific herbs up to 60 cm tall. Roots flexuous, cylindrical, white or yellowish brown with yellow apex. Stems erect, superposed, with 7 − 10 internodes, 3.6 − 20 × 0.1 − 0.3 cm, covered completely by lepanthiform sheaths, these light brown to golden brown, with prominent nerves, 1.5 − 3.6 cm, the ostium microscopically muricate, apex acuminate. Leaves erect, 4.2 − 7.9 × 1.4 − 2.2 cm, blades ovate to oblong, light green, attenuate, tridenticulate apically, base cuneate, contracted into a petiole 7 − 9 mm long. Inflorescence 12.5 − 24 cm, longer than the leaves, one or two per stem, producing 20–30, widely spaced, successively opening flowers, one or two at a time; peduncle filiform, 4 mm long, ca. 0.3 mm in diameter, surrounded by a basal bract. Floral bracts 4 mm long, papillose, obliquely infundibuliform, apiculate. Ovary 3 mm long, obpyramidal, with irregular keels. Flowers ca. 16 × 5 mm, sepals entirely yellow or with a basal red spot, petals yellow with edges of the upper lobe indistinctly red, lip yellow with the base and edges of the blades red or pink, column yellow, pink or red and anther white or yellow. Dorsal sepal 8.5 × 5.0 mm, slightly concave, triangular-ovate, acute-acuminate, 3-veined, veins prominent on the back. Lateral sepals 7.5 × 2.6 mm, connate to their middle, obliquely ovate with divergent, acute-acuminate apex, 2-veined. Petals ca. 1 × 5 mm, transversely bilobed, lobes subequal, with a small apicule, 1-veined, minutely pubescent; upper lobes lanceolate-oblong, oblique, overlapping the middle and diverging in the upper part, subacute, lower lobes proportionally shorter, lanceolate-oblong, subacute. Lip with blades obliquely lanceolate, more or less flat, microscopically pubescent, close to each other in their proximal part and divergent at the apex, covering the basal half of the column, base of the blades rounded, apical part acute-attenuate, ca. 2.0 × 1.6 mm. Connective cuneate, papillose, base of the lip connate with the base of the column, sinuous, obtuse, with the appendix apex yellow, orbicular, pubescent and the base with a prominent tuft of white hairs. Column slightly arched, a little wider apically, somewhat compressed dorsiventrally, ca. 1.6 × 0.8 mm; clinandrium covering the lower half of the anther. Anther dorsal, stigma ventral, round. Rostellum with the apex rounded, yellow. Capsule ovoid with persistent perianth.

Distribution: — Lepanthes obandoi grows sympatrically with Lepanthes ibarrense and is known only from the type locality. It grows terrestrially along the edges of the maintenance path of the drinking water system found in this sector and was also observed growing on roadside embankments along the path or on rocks. So far, no individuals have been found growing epiphytically. It is probable that this species may occur in Cayambe-Coca Ecological Reserve due to its proximity to this protected area.

Conservation status: — Lepanthes obandoi is locally abundant, grows in small colonies along the maintenance path of the drinking water network system and other pathways. Several populations of this species are scattered in an area larger than 10 km 2. As with L. ibarrense , the advance of the agricultural frontier is one of the most significant threats. However, L. obandoi seems to be a colonizing species that thrives in moderately disturbed areas, and this factor, along with its relatively large population size, may represent an advantage for its survival, in contrast with L. ibarrense .

Eponymy:—Named in honour of Eduardo Obando, a young engineer of renewable natural resources and orchid enthusiast who discovered and registered these species for the first time.

Discussion: — Lepanthes obandoi is similar to L.muscula from Ecuador and Colombia, but the latter is distinguished by its smaller plants up to 30 cm in height (vs. up to 60 cm in height with superposed stems), ovate-elliptic leaves (vs. ovate-oblong), transversely oblong petals (vs. oblong to lanceolate-oblong), lip with oblong blades (vs. obliquely lanceolate) and a minute appendix with a pair of small rounded lobes (vs. elongate with a pubescent orbicular apex and prominent tuft of basal white hairs).

Lepanthes obandoi also resembles florally Lepanthes guanacasensis Luer & Escobar (1997: 97) from Colombia, but in the latter the petals have the lobes subequal (vs. petals with the upper lobe significantly larger than the lower lobe), lip blades essentially glabrous, oblong with rounded apex (vs. microscopically pubescent, obliquely lanceolate, with acute-attenuate apex) and a tiny appendage that is minutely bilobed apically (vs. elongate with an orbicular-pubescent apex and a prominent tuft of white basal hairs).

Moreover, L. obandoi resembles Lepanthes osiris Luer & Escobar (1994: 103) , which has shorter stems up to 8 cm (vs. up to 20 cm), petals with narrowly ovate lobes, with an acute apex (vs. petals with lanceolate-oblong lobes with subacute apex), ovate lip blades (vs. obliquely lanceolate) and an oblong appendix bifid at the apex (vs. appendix elongate with an orbicular-pubescent apex and a prominent tuft of white hairs at the base).

Figures

FIGURE 3. Lepanthes obandoi. (A). Habit. (B). Flower. (C). Sepals and petals dissected. (D). Frontal view of the lip with column. (E). Frontal view of the lip extended without the column. (F). Lateral view of the ovary, lip and column. Drawn by F. Tobar from the holotype, Tobar et al. 1983.

FIGURE 4. Lepanthes obandoi. (A) Plant growing in situ. (B). Front view of the flower. (C). Lateral view of the flower. Photograph by F. Tobar from the plant that provided the holotype, Tobar et al. 1983.