A New Species Of Dichaea (Orchidaceae: Zygopetalinae) From The Andes Of Colombia
Alomía, Yasmin A.
Sambin, Aurelien
Otero, J. Tupac
Stevenson, Pablo R.
Phytotaxa
2021
2021-09-23
521
1
39
47
9L9V6
Alomia & Sambin
Alomia & Sambin
2021
[136,534,1268,1295]
Liliopsida
Orchidaceae
Dichaea
Plantae
Asparagales
1
40
Tracheophyta
species
andina
sp. nov.
Type:— COLOMBIA. Valle del Cauca, Western Cordillera, El Cairo, Reserva Comunitaria Cerro El Inglés, 4° 45’ 31.5” N, - 76° 17’ 07.6” W, 2303 m, Andean cloud forest, epiphytic in remnant primary forest, April 09, 2017. Y. A. Alomía 216( holotype: ANDES; isotypes: CUVC, COL; Figs. 2–5). Dichaea andinadiffers from D. lagotis Reichenbach (1876: 112)in the broadly anchoriform lip ( vs.sagittate), with the hypochile transversely subrounded ( vs.subquadrate) and the epichile transversely narrowly elliptic, briefly apiculate ( vs.oblong acute). It differs from D. pendula( Aublet 1775: 819) Cogniaux (1903: 182)in the caespitose plants ( vs.plants not caespitose), the leaves without cross-venation ( vs.with cross-venation), and the inflorescence straight, produced under the foliage ( vs.geniculated, above the foliage). Plantepiphytic, caespitose, up to 2 mlong. Basal roots 0.6–0.9 cmin diameter, brownish, filiform, flexuous. Caulinar roots ca. 0.4 cmin diameter, greenish, filiform, flexuous, glabrous, protruding from the leaf sheaths. Stemsup to 100 × 0.40–0.45 cmand 0.12–0.18 cmthick, covered by conduplicate sheaths, frequently branching, flattened, pendent, arched to erect at the apex. Leaves2.5–3.7 × 0.5–0.9 cm, green to olive green, distichous along stem, ovate to elliptic-ovate, distinctly apiculate, the margin entire except at the serrulate apex, thin-textured herbaceous, abaxially with a prominent midvein and conspicuous parallel secondary veins. Inflorescenceone per node, occurring below the foliage; peduncle 1.4–1.8 × 0.6–1.0 cm, terete, straight, with three tubular overlapping bracts. Floral bractdouble, the outer bract ca.6 × 3 mm, widely ovate, acuminate, the inner bract ca.7 × 0.8 mm, linear, acuminate. Ovary 3 mmlong, densely muricate. Flowersin anthesis for 1-2 days, with a sweet fragrance detected between 9:00–15:00 h, sepals and petals pale pink spotted with violet, sepals warty on abaxial surface, lip white with the apical edge outlined in violet as well as two violet spots on the base. Dorsal sepal9.6 × 3.8 mm, concave, ovate-lanceolate, acute. Lateral sepals9.2 × 4.1 mm, concave, slightly asymmetrical, elliptic, lanceolate, acute. Petals7.5 × 3.2 mm, elliptic oblong, acute, margins lightly undulated. Lipsubsessile, distally 3-lobed to anchor-shaped, fleshy, glabrous; hypochile ca.4.5 × 2.7 mm, transversely subrounded forming distinct glabrous shoulders, lateral lobes about 2 mmlong, narrowly triangular, filiform, more or less spreading; epichile ca.4 × 2.3 mm, transversely narrowly elliptic, briefly apiculate. Column5 × 4 mm, suberect, the base subterete, with two obliquely subquadrate rounded wings, ciliate along the margin; stigma transversely widely elliptic-ovate, strongly depressed; infrastigmatic ligule 1.2 × 0.8 mm, linear, projecting forward, hispid, truncate and bifid at the apex. Anther 1.1 × 1.5 mm, helmet-shaped, 2-celled. Pollinia4, orbicular, in two superposed pairs of different size; stipe chalice-shaped; viscidium rectangular. Fruit1.8 × 1.4 cm, ovoid, greenishbrown, densely muricate, exocarp about 2 mmthickness, trichomes broadly triangular, acuminate. Seeds ca.160 × 60 µm, hyalines and fusiform, pale yellow in immature stages and brownish when ripe. FIGURE 1. Known population of Dichaea andina. Bosque de San Antonio (BSA), Bosque El Aguapante (BAP), Parque Nacional Natural Cueva de los Guácharos (GUA), Reserva Comunitaria Cerro el Inglés (RCI). Additional material studied:— COLOMBIA. Valle del Cauca, Western Cordillera, El Saladito, Bosque de San Antonio, 3°29’45.6”N, - 76°37’29.1”W, 2078 m, Andean cloud forest, epiphytic in remnant primary forest, 11/05/2017, Y. A . Alomía217( ANDES, COL, CUVC). Huila, East Cordillera, Palestina, Parque Nacional Natural Cuevade los Guácharos, 1°36’26.0”N, - 76°05’45.2”W, 2189 m, Andean cloud forest, epiphytic in primary forest, 21/04/2017, Y. A . Alomía218( ANDES, COL, CUVC), P . Stevenson-2934( ANDES). Antioquia, Central Cordillera, San Antonio de Prado, 6°14’42.8”N, - 75°40’36.0”W, 2284 m, Andean cloud forest, epiphytic in remnant primary forest, 10/10/2017, Y. A . Alomía230( ANDES, COL, CUVC).
Ecology:— Dichaea andinagrows in the wet mountainous forests of the Andes mountain range at elevations between 1800 and 2400 m, with a mean temperature of 14.5 °C and a mean relative humidity of 99 %. The plants are found growing on both living trees ( Annonaceae, Arecaceae, Clusiaceae, Cyatheaceae, Lauraceae, Melastomataceae, Myrtaceae, Piperaceae) and dead trunks, usually in deep shaded areas. Two flowering peaks were recorded twice, one in April–May and another in October–November, although there may be occasional flowering year round. Plants are completely allogamous. Flowers are pollinated by male Euglossabees which are attracted by volatile floral fragrances primarily composed of 2-(4-methoxyphenyl) ethanol (4-2-hydroxyethyl anisole) and 2-methoxy-phenol ( o-Guaiacol) ( Alomía et al.2018).
Etymology:—The specific epithet is designated for two purposes: first, to honor the Andean forests (Andes mountain range) and second, in recognition of the Universidad de Los Andes, for the academic and institutional support it provided to the first author during her doctoral studies.
3358417301
2017-04-09
Y, A, ANDES, CUVC, COL
El Cairo & Reserva Comunitaria Cerro El Ingles
Colombia
2303
4.75875
Western Cordillera
1
-76.285446
1
40
1
Valle del Cauca
holotype
3358417306
2017-05-11
Y, A
Colombia
Western Cordillera
2078
3.496
Bosque de San Antonio
1
-76.62475
El Saladito
2
41
1
Valle del Cauca
3358417302
[189,614,1918,1944]
ANDES, COL, CUVC
Colombia
Alomia
2
41
1
Valle del Cauca
3358417305
2017-04-21
Y, A
Colombia
East Cordillera
2189
1.6072222
Parque Nacional Natural Cueva
1
-76.095894
Palestina
2
41
1
Huila
3358417303
[136,593,1990,2016]
ANDES, COL, CUVC, P
Colombia
Alomia
2
41
1
Huila
3358417307
2017-10-10
Y, A
Colombia
2284
6.245222
San Antonio de Prado
1
-75.67667
Central Cordillera
2
41
1
Antioquia
3358417304
[187,601,2062,2088]
ANDES, COL, CUVC
Colombia
Alomia
2
41
1
Antioquia