Lepanthes dubbeldamii B.T.Larsen, 2014

Larsen, Bruno, 2014, Three new species of Lepanthes (Orchidaceae), Phytotaxa 175 (5), pp. 275-280 : 275-277

Lepanthes dubbeldamii B.T.Larsen , sp. nov. ( Fig.1 )

This species is most similar to the Ecuadorian Lepanthes alopex , but is distinguished by its longer peduncle, petals with a truncate upper lobe, oblong blades of the lip and densely pubescent, thickened sinus with an oblong, geniculate, and pubescent, appendix.

Type:— VENEZUELA. Sucre: Peninsula de Paria, Cerro de Humo , 10.41’.15” N, 62.37’.46” W, 1,800 m , collected in the wild 22 December 2007 by P . Dubbeldam 200715, flowered in cultivation in Paningen, The Netherlands, 11 November 2013, Wiel Driessen s.n. (holotype LISI-1593/2013, LISI!) .

Plant small, epiphytic, caespitose; roots slender but thicker than the ramicauls. Ramicauls slender, erect, 7.5 cm long, enclosed by 7–15 lepanthiform sheats, with oblique, acuminate and dilated ostia, recurved and microscopically ciliate at the edge, microscopically ciliate along the ribs. Leaf erect, thinly coriaceous, 2.8–4.5× 1.4–3.8 cm, ovate, acute, abruptly long-acuminate, minutely 3-dentate at the apex, shortly attenuate at the base into a petiole 2 mm long. Inflorescence an erect raceme longer than the leaf, arching above the middle, up to 4.5 cm long, successively many-flowered, flowers congested and distichous along the rachis lax flowered below, becoming congested above, distichous, successively many-flowered, deflexed bellow the middle, raceme up to 4.5 cm long, borne beyond the apex of the leaf by a filiform, flexuous peduncle 6 cm long on top of the leaf; floral bracts, glabrous, 1.3 mm long; pedicels 2.7 mm long; ovary carinate, 1.03 mm long. Sepals translucent-rose, ovate, acute; dorsal sepal ovate-triangular, acute, acuminate, 4.03 × 3.07 mm, 3-veined, connate to the lateral sepals for 0.9 mm; lateral sepals ovate, diverging, acute, acuminate, 3.29 × 1.8 mm, connate for 1.5 mm, 2-veined. Petals red, densely microscopically pubescent, transversely bilobed, 0.36 × 2.64 mm, upper lobe rectangular, apex truncate, 0.51 × 1.34 mm, lower lobe oblong-triangular, obtuse, 0.32 × 1.3 mm. Lip red, bilaminate, blades oblong with rounded ends, microscopically densely pubescent, 1.2 mm long, connectives densely pubescent, broad, cuneate, erect, the body broad, densely pubescent, connate to the base of the column, sinus thickened, densely pubescent with a oblong, uncinate, appendix 0.27 mm long. Column light rose, conical, microscopically pubescent, 1.24 mm long, anther apical, stigma ventral. Capsule unkown.

Etymology:— Named in honor of Piet Dubbeldam of Heijningen, The Nederlands, who discovered this species.

Distribution and habitat:— Venezuela, only know from one locality in Cerro de Humo, in Peninsula de Paria, where it grows as epiphyte forming colonies on the lower branches of trees in very humid cloud forest at about 1,800 m elevation.

Comments: —This species, apparently is endemic to Cerro de Humo, is similar to the Ecuadorian Lepanthes alopex Luer & Hirtz in Luer (1996: 33). Both species are characterized by the ovate, long-acuminate leaves and by the long-pedunculate, congested raceme. Lepanthes dubbeldamii differs from Lepanthes alopex by the longer peduncle, the raceme deflexed below the middle, the carinate ovary, the petals with a truncate upper lobe, and by the thickened sinus with an oblong, uncinate, densely pubescent appendix.

Figures

FIGURE 1. Lepanthes dubbeldamii B.T.Larsen.A. Segment of inflorescence with one flower in frontal view. B. Dissected flower. C. Lip and column detail, dorsal view. D. Expanded lip, frontal view. E. Ovary, column and lip, lateral view. F. Habit. Drawn from the holotype by B. Larsen.