Four New Teagueia (Orchidaceae: Pleurothallidinae) from the Upper Río Pastaza Watershed of East-Central Ecuador

LANKESTERIANA 17(2): 261—278. 2017. doi: http://dx.doi.org/10.15517/lank.v17i2.30159 FOUR NEW TEAGUEIA (ORCHIDACEAE: PLEUROTHALLIDINAE) FROM THE UPPER RÍO PASTAZA WATERSHED OF EAST-CENTRAL ECUADOR LOU JOST1,2,4 & ANDERSON SHEPARD3 1 Fundacion EcoMinga, 270 12 de noviembre and Luis A Martínez, Baños, Tungurahua, Ecuador 2 Jardín Botánico de Quito, Parque Carolina, Quito, Pichincha, Ecuador 3 3285 Roland Drive, Santa Cruz, California USA 4Author for correspondence: [email protected] ABSTRACT. The genus Teagueia, once considered a minor genus with few species, has undergone a surprisingly diverse local evolutionary radiation in the upper Río Pastaza watershed of the eastern Andes of Ecuador. All species forming this local radiation are long-repent, in contrast to the rest of the species in the genus. Six species from this local radiation have been described previously, and four additional species are described here. The four new species are each distinguished by their particular lip shapes, differences in flower sizes, and differences in leaf textures. The new species, like the others in this radiation, all have extremely narrow distributions. RESUMEN. El género Teagueia, una vez considerado como un género menor con muy pocas especies, ha experimentado una sorprendente radiación evolutiva de alta diversidad en la cuenca alta del Río Pastaza ubicada en los Andes orientales del Ecuador. Todos los miembros de esta radiación local comparten un habito largo-reptante, en contraste con el resto de las especies del género. Seis especies de esta radiación local fueron descritas anteriormente; aqui se describe cuatro especies adicionales. Cada una de las cuatro especies nuevas se distingue por la forma particular de sus labelo, diferencias en los tamaños de sus flores, y diferencias en las textura de sus hojas. Todas las especies nuevas, al igual que las otras de esta radiación, tienen distribuciones extremadamente reducidas. KEY WORDS: Teagueia, Pleurothallidinae, Platystele, Orchidaceae, Ecuador Introduction. In the first volume of his classic Icones known at the time of the earlier publications, merited Pleurothallidinarum, Carl Luer (1986) proposed their own genus, Teagueia (Luer) Luer. The two Teagueia Luer as a new subgenus of Platystele Schltr. new species were T. tentaculata Luer & Hirtz from (Orchidaceae: Pleurothallidinae), to accommodate three Ecuador and T. lehmanii Luer from Colombia. A tiny aberrant large-flowered Andean species: P. phasmida new species, T. portillae Luer, was added eleven Luer & R.Escobar and P. rex Luer & R.Escobar from years later (Luer 2002). All of these Teagueia species Colombia, and P. teaguei Luer from Ecuador (Luer have very restricted distributions; each is known 1986). These three species had much larger plants and only from a single locality. Teagueia lehmannii Luer flowers than typical Platystele, with multiple veins in has only been collected once, one hundred years the sepals, while the rest of the species of Platystele had ago (Luer 1991), and has not been seen in modern single-veined sepals. The most distinctive trait of the times. Nevertheless, the high montane habitat of the members of the new subgenus was the involute margin genus is notoriously inaccessible, so the individual of the lip, forming a central channel or orifice near the species and the genus as a whole may have somewhat lip’s apex (Luer 1986). wider distributions than the sparse collection A fourth species, Platystele zeus Luer from records indicate. The recent discovery of T. moisesii Ecuador, with even larger flowers than the first three Chocce & M.E.Acuña in Peru (Chocce et al. 2011) species, was soon added to subgenus Teagueia (Luer highlights the incompleteness of our knowledge of 1990). The following year Luer (1991) found that the distribution of this genus. these four distinctive yet morphologically similar The eight Teagueia species mentioned above, species, along with two species that had not been the so-called “typical” Teagueia species, grow in Received 30 April 2017; accepted for publication 31 July 2017. First published online: 14 August 2017. Licensed under a Creative Commons Attribution-NonCommercial-No Derivs 3.0 Costa Rica License. 262 LANKESTERIANA FIGURE 1. Cerro Mayordomo, where the first long-repentTeagueia species were discovered. Photograph by Lou Jost. isolated populations without sympatric congeners, rhizome segments between ramicauls, with only one giving the impression that the genus was one of or two roots per ramicaul, and no roots on the rhizome the smaller pleurothallid genera. This changed in internodes which lack ramicauls. The flowers are 2000 when four new Teagueia species (T. alyssana also different between the two groups of species. Luer & L.Jost, T. cymbisepala Luer & L.Jost, T. Seven of the eight “typical” Teagueia species have jostii Luer, and T. sancheziae Luer & L.Jost) were a conspicuous, often ciliate callus near the base found in one small section of trail at 3100 m on of the lip (the exception is the tiny T. portillae), Cerro Mayordomo in the high Andes of the upper while all the long-repent Teagueia species lack this Río Pastaza watershed (Fig. 1) in east-central basal callus. As suggested by their morphological Ecuador (Luer 2000, Jost 2004). Since that time cohesion, genetic analysis reveals that these new we and our students (Scot Grossman, Ali Araujo, species belong to a single monophyletic clade which and Pailin Weddel) have discovered many more has no known representatives outside the upper Río species of Teagueia in the same area. Two of these, Pastaza watershed (Jost et al. in prep.). T. barbeliana L.Jost & Shepard and T. puroana The present paper describes four new species L.Jost & Shepard, were recently described (Jost & in this clade of long-repent Teagueia. A DNA-based Shepard 2011). All these new species have clear phylogeny is also being prepared for publication morphological similarities that unite them and elsewhere. With so many closely related species distinguish them from the eight “typical” Teagueia packed into such a small area, and with many of them species. Most notably, all of these new Teagueia growing sympatrically on the same mountain peaks, species from the upper Río Pastaza watershed this is one of the most diverse and puzzling local are long-repent, with three (very rarely two) long evolutionary radiations in the Orchidaceae. LANKESTERIANA 17(2). 2017. © Universidad de Costa Rica, 2017. JOST & SHEPARD — New Teagueia species 263 TAXONOMIC TREATMENT 3.6–3.9 × 2.5–2.7 mm; lateral sepals two-veined, 3.1–3.4 × 1.7–1.9 mm, connate for 2 mm, forming Teagueia kostoglouana L.Jost & A.Shepard, sp. a concave broadly elliptical-ovate synsepal; petals nov. obovate, acute, microscopically ciliate, one-veined, TYPE: Ecuador. Tungurahua: south of the Río Pastaza, 2.4–-2.6 × 1.3–1.4 mm; lip yellow heavily suffused Cerro Negro, lat. -1.43°, long. -78.37°, 3000m, with red-purple, three-veined; basal segment 0.8– terrestrial in deep moss, April 30 2002, L. Jost, A. 0.9 mm long, closely appressed to column, rigidly Shepard, P. Weddel, A. Araujo 4037 (holotype: QCA! attached to column by a narrow ligule, side lobes 1 both pressed plant and spirit flower, from a single mm long embracing the column, then widening and gathering from the same individual; isotype QCNE! spreading to form a collar around the column, collar spirit). Fig. 2–4. flattened in the same plane as the disc; disc deltoid, microscopically ciliate, 2.7–2.9 long and 1.3–1.4 mm DIAGNOSIS. This species (Fig. 2) is most similar to T wide at top, disc with a central orifice;column terete, sancheziae (Fig. 3) but is distinguished from all other 1.8–2.0 × 0.8 mm, straight, anther hooded, apical, described species by the combination of long nearly anther cap white, covering two pyriform yellow straight column more than 40% as long as the dorsal pollinia united by a drop-like viscidium; the stigma sepal, and the disc of the lip more than 50% as long as single-lobed. the dorsal sepal and reflexed more than 130°. All other species have proportionally much shorter or sigmoid PARATYPES: Ecuador. Tungurahua: north of the Río columns, and have lip discs proportionately shorter or Pastaza: Cerro Negro, lat. -1.44°, long. -78.37°, 3400 less reflexed. m, terrestrial in deep moss, April 30 2002, L. Jost, A. Herb, terrestrial, long-repent; roots ca.0.8 Shepard, P. Weddel, A. Araujo 4030 (QCA!-spirit); mm thick. Rhizome with three (rarely two) major Cerro Candelaria, lat. -1.46°, long. -78.30°, 3100 segments, each 4–11 mm long, 1.6–2.8 cm between m, terrestrial in deep moss, Jan 20 2003, L. Jost, R. ramicauls. Ramicauls slender, ca. 2 mm long, Kunstaetter, D. Kunstaetter 5278 (QCA!; QCA- consisting of two equal segments, each enclosed by spirit!). a thin, gray, ribbed, loosely imbricating, apiculate, VARIATION: The type specimen and most others have sparsely verrucose persistent sheath, the warts mainly an unsaturated orange-yellow ground color, but near the top of the sheath; the sheath of the basal individuals can be found with a more yellow ground segment 2–3 mm long, the sheath of the distal segment color, and the amount of red-purple coloration in the 5–8 mm long. Leaf erect, coriaceous, verrucose, lip can vary (Fig. 4). Flower size varies by about 15% elliptical, the blade 2.0–2.2 × 1.0-1.2 cm, apex with a but shape is fairly consistent, though specimens from small mucronate sinus, base gradually narrowing into Cerro Candelaria have less reflexed floral parts. Leaf a slender petiole 1.1-1.4 cm long, emerging from the width relative to length varies considerably. Like most apex of the ramicaul. Inflorescence a loose, more or long-repent Teagueia species, the lip of the flower less erect, strict, successive, distantly many-flowered begins to curve sharply forward at the orifice when the raceme arising from the apex of the ramicaul, up to flower is old.

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