Telipogon sonia-juaniorum Zambrano, Bogarín & Solano, 2018

Romero, Bosco Javier Zambrano, Bogarín, Diego & Solano, Rodolfo, 2018, Telipogon sonia-juaniorum (Orchidaceae: Oncidiinae) a new species from Southwestern Ecuador, Phytotaxa 340 (2), pp. 167-174 : 168-172

Telipogon sonia-juaniorum Zambrano, Bogarín & Solano sp. nov. Figs. 1–4 .

Species haec T. standleyi Ames similis sed foliis elliptico-ovatis, marginibus crenulatis, petalis oblique orbiculari-ovatis, labello elliptico, obtuso differt.

Type:— ECUADOR. El Oro: Cantón Piñas, sector Piñas Grande , 1200 m, 12 December 2007, B. Zambrano 479 (Holotype in QCNE; isotype in QCNE [in spirit]) .

Small, epiphyte herb, up to 8.0 cm tall including the inflorescence. Roots thick, fleshy, slightly flattened, whitish, greenish at the tips, 2–3 mm thick. Leaves up to 3, forming a basal rosette, erect, distichous, membranous, elliptic-ovate, acuminate, minutely crenulate along the margins, 5.0–7.0 × 2.5–3.0 mm. Inflorescence developed from the axils of the leaves, simple or branched, 1–3 flowered, 55 mm long; peduncle flattened, slightly and progressively widened toward the apex, green, 0.3 mm thick; covered with 6 bracts which are reduced in size upwards, winged, slightly overlapping, distichous, obovate-lanceolate, acute, green, translucent, 2.0– 2.5 mm long, the wings resembling an obsolete blade; rachis strongly compressed, 3-winged, green, 0.6 mm thick. Floral bracts membranous, ovate-triangular, acute, green, translucent, 1.0– 1.5 mm long. Ovary with a very short pedicel, slightly arching, somewhat ellipsoid, attenuate at the base, green-purplish, 2.5 mm long and 0.8 mm thick. Flowers minute, successively opened, 4.5 mm diameter; sepals and petals purple, yellowish toward their apices, lip dark purple, column and anther purple. Dorsal sepal concave, triangular-ovate, acute, slightly reflexed, entire along the margins, translucent, 1-nerved, 2.3 × 1.8 mm. Lateral sepals concave, triangular-ovate, slightly oblique, acute, reflexed, shortly apiculate, entire along the margins, translucent, 1-nerved, 2.2 × 1.5 mm. Petals concave, obliquely orbicular-ovate, widely obtuse, shortly apiculate, minutely ciliate along the margins, the hairs retrorse, translucent, 3-veined, 2.0 × 1.5 mm. Lip entire, sessile, separate from the column by a basal low sulcus, fleshy-thickened at the basal mid, elliptic, obtuse, shortly apiculate, densely papillose on ventral surface, minutely ciliate along the margins, the hairs retrorse, 3-veined, 2.4 × 1.3 mm. Column very short, single, 0.6–0.7 mm long, 0.4 mm wide, the clinandrium projected into a narrow filament, apically recurved, shortly pilose at the base on the ventral surface, adorned with 3 tufts of prominent hairs on the dorsal surface, the hairs reddish, rigid, septate, simple to rarely furcate, 0.2–0.7 mm long. Stigma apical, suborbicular, slightly concave. Anther apical, cordiform, apparently bilocular, membranous, ca. 0.8 × 0.7 mm. Pollinarium 0.5–0.6 mm long, formed by 4 pollinia in two pairs of different size, yellow, obovate, laterally compressed, with a Y-shaped caudicle and a hooked viscidium. Capsule narrowly ellipsoid, with a persistent perianth, 4.0–5.0 mm long (4.5–5.5 mm including the remnant column), ca. 2.0 mm in diameter when mature.

Distribution and habitat: —Up to now Telipogon sonia-juaniorum is only known from three localities in southwestern Ecuador, in El Oro province, between 1,100 and 1,300 m elev., in semi-deciduous montane forests ( Fig. 3 ). The species grows as epiphyte on tree and shrub branches of Mauria sp. ( Anacardiaceae ) and Miconia sp. ( Melastomataceae ).

Floral biology: —In culture T. sonia-juaniorum flowered between June and September. Ripen fruits were observed between July and August.

Eponymy: —In honor of Sonia Romero, Juan Zambrano and Juan Pablo Zambrano, parents and brother of the first author, who have contributed substantially in his research of the Orchidaceae family from Ecuador.

Additional specimens:— ECUADOR. El Oro: Cantón Piñas, N of Piñas, sector San Jacinto, 1300 m, 12 August 2016, B. Zambrano 1798 (QCNE). Cantón Balsas, sector Santa Elena, 1248 m, 15 Sepetember 2017, B. Zambrano 2168 (QCNE).

Comments: —The most similar species with the new taxon are the Costa Rican Telipogon standleyi , T. boylei , and T. lankesteri . Telipogon standleyi can be distinguished from T. sonia-juaniorum by its lanceolate and marginally entire leaves (vs. elliptic-ovate, crenulate), slightly oblique petals (vs. evidently oblique), oblong-ovate lip (vs. elliptic), ventrally glabrous column (vs. minutely pilose), and furcate hairs (vs. simple to rarely furcate) ( Ames 1925, Bogarín 2012). Telipogon boylei , originally described as Stellilabium boylei Atwood (1989 : t. 1392), is different by its ovate leaves (vs. elliptic-ovate), green with purple flowers (vs. purple with yellow), elliptic lateral sepals (vs. triangular-ovate), elliptic subrounded petals (vs. orbicular-ovate and widely obtuse), longer and more or less sagitate lip (5.0 mm vs. 2.4 mm, elliptic), and furcate hairs (vs. simple to rarely furcate). Telipogon lankesteri differs by having lanceolate leaves (vs. elliptic-ovate), ovate-lanceolate sepals (vs. triangular-ovate), ovate petals (vs. orbicular-ovate), and oblonglanceolate lip (vs. elliptic) ( Ames 1923). On the other hand, T. boylei , T. lankesteri and T. standleyi has not been reported for Colombia and Peru, so the geographic disjunction among the southernmost populations of these species and that from T. sonia-juaniorum allows recognizing them as different taxa.

Among its Ecuadorian congeneric Telipogon sonia-juaniorum is similar to T. alexii and T. morganiae . The first species was originally described as Stellilabium hirtzii by Dodson (1984: pl. 982), it is distinguished by its elliptic leaves (vs. elliptic-ovate), pale cream flowers (vs. purple with yellow), lanceolate sepals (vs. triangular-ovate), petals linear-elliptic, 1-veined (vs. orbicular-ovate, 3-veined), ventrally glabrous column (vs. pubescent), and without hairs (vs. simple to rarely furcate). On the other hand, T. morganiae , originally described as Stellilabium morganiae by Dodson (1980: pl. 335), is different by its marginally entire leaves (vs. crenulate), green with red flowers (vs. purple with yellow), orbicular and 5-veined petals (vs. orbicular-ovate, 3-veined), lanceolate and acuminate lip (vs. elliptic, obtuse), and minute hairs (vs. prominent).

The Mexican T. amoanus and the Panamanian T. morii , originally described as Stellilabium morii by Dressler (1999: 473), are other two similar species. Telipogon amoanus is different by its rose flowers (vs. purple with yellow), sharply oblique lateral sepals (vs. slightly oblique), oblanceolate petals (vs. orbicular-ovate), and triangular-sagitate lip (vs. elliptic) ( Salazar & Hágsater 1992, Bogarín 2012). Finally, T. morii differs from T. sonia-juaniorum by its marginally entire leaves (vs. crenulate), obovate, 5-veined petals (vs. orbicular-ovate, 3-veined), oblong-ovate lip (vs. elliptic), slightly 3-lobed column (vs. single), and furcate hairs (vs. simple to rarely furcate). A summary of the comparisons between T. sonia-juaniorum and the above mentioned species is provided in Table 1.

Although T. sonia-juaniorum is morphologically similar to other exclusively Central American species, Williams et al. (2005) found that Telipogon s.l. contains at least three clades: 1) a Central American clade sister to the South American species formerly treated under Stellilabium , 2) one South American clade of Telipogon klotzscheanus - T. nervosus - T. vargasii ; and 3) another South American clade of T. venustus - T. ariasii - T. valenciae complex. So, the species (formerly Stellilabium ) from Central America and South America are not strictly mixed into a single clade. Thus, a further phylogenetic evaluation of T. sonia-juaniorum is needed to confirm its relationship among the Central- South American species.

Conservation status: —This rare species has not been found in other localities from Ecuador, it is necessary to consider it as a restricted endemic. The only known populations for this species are in remnant forest disturbed by human activities, where they exhibit low densities (1–2 plants per phorophyte) and apparently, they are subject to common extinction-recolonization events, they are isolated, out of protected areas. Telipogon sonia-juaniorum could be classified as EN (Endangered) according to the IUCN criteria ( IUCN 2014).

Figures

FIGURE 1. Telipogon sonia-juaniorum Zambrano, Bogarín & Solano. A. Habit. B. Detail of the leaf. C. Flower, frontal view. D. Flower dissection. E. Detail of the petal. F. Detail of the lip. G. Ovary, column and lip, lateral view. H. Ovary with column, lateral view, and details of the column. I. Anther and pollinarium. J. Capsule. Plate by B.J. Zambrano based on B. Zambrano 479 and 1798.

FIGURE 2. Telipogon sonia-juaniorum Zambrano, Bogarín & Solano. A. Habit. B. Detail of the leaf. C. Flower, frontal view. D. Flower dissection. E. Detail of the petal and lip. F. Ovary, column and lip, lateral view. Drawn by B.J. Zambrano based on the holotype.

FIGURE 3. Known localities for Telipogon sonia-juaniorum in Southwestern Ecuador. Map by B.J. Zambrano.

FIGURE 4. A. Telipogon sonia-juaniorum (B. Zambrano 1798). B. Telipogon standleyi (D. Bogarín 5138). Photographs by B.J. Zambrano (A), and D. Bogarín (B).