Uleiorchis longipedicellata A. Cardoso & Ilkiu-Borges, 2015

Cardoso, André Luiz De Rezende, Ilkiu-Borges, Anna Luiza & Rodrigues, Tarcísio Magevski, 2015, A new species of Uleiorchis (Gastrodieae, Orchidaceae) from the Brazilian Amazon, Phytotaxa 205 (2), pp. 117-122 : 118-119

Uleiorchis longipedicellata A. Cardoso & Ilkiu-Borges , sp. nov. ( Figs. 1 & 2 )

Uleiorchis longipedicellata differs from U. ulei , U. pratënsis and U. liesneri by the extremely elongated pedicel, ligulate lip with a distal round dilatation, and elliptic, smooth stigmatic zone.

Type:— BRAZIL. Pará: Parauapebas, Carajás Range, N 5 Leste, 12 November 1998, 690 m, in a thick layer of leaf litter in the transition between rain forest and ironstone outcrops vegetation, A. Cardoso 721 (holotype, IAN 168.902).

Micoheterotrophyc, erect herb, 8.1–23.3 cm tall. Rhizome with a series of one or more, dorsiventrally compressed, verrucose tubers. Roots emerging from an annular thickening, up to 82 mm long, 1 mm wide. Stems erect, terete, glabrous, fragile, pinkish-white to pale green-purple towards the apex, aphyllous, with 1–3 sheaths; sheaths deltoid, 3.2 × 3.5 mm, erect, brown, papyraceous. Inflorescence a 1–4-flowered raceme. Bracts broadly ovate, 3.6 × 3.8 mm, similar to the stem sheaths. Pedicels pinkish-white, erect to spreading, initially ca. 2 mm, elongating with the development of the fruits up to 227 mm long, when the fruits ripen and the seeds are dispersed. Flowers campanulate, pale-white to pale-brown becoming brown distally, lip black from the base up to ¾ of the lip, distally yellow, erect to spreading. Sepals and petals fused into a cup with ventral slit, this internally occluded by the lip; perianth cup membranous, 9.3 × 11 mm, glabrous; free portions of petals and sepals spreading; free parts of sepals triangular, to 1 mm long, apex acute; free parts of petals inconspicuous, adhered to dorsal sepal. Lip membranaceous, basally fleshy, inserted at the column base, ligulate to ¾ with a distal round dilatation, 12 × 2 mm, subacute to obtuse at apex. Column white, winged, 9 × 1 mm, glabrous; stigmatic zone elliptic, 3–4 mm long, glabrous, smooth. Anther white, 2 mm long, erect. Pollinia not seen. Ovary oblong-ovoid, ca. 1 mm long, whitish-brown, glabrous. Fruit erect, ovoid, 19–23 mm long, pinkish-white to pale green-purple, ribs thickened, persisting after dehiscence.

Distribution and ecology:— This remarkable new species is only known from tree sites in the Carajás Range, located in two municipalities. Besides the type, from Parauapebas, another population of Uleiorchis longipedicellata was collected and photographed ( Fig. 2 ) in the Eastern Range of the Carajás National Forest, in the municipality of Curionópolis. Both collections sites presented a thick layer of leaf litter on the forest ground, and where situated from 500 to 690 m elevation, with ca. 2,000 mm rainfall per year. The species was found forming small populations on the edge of plateaus, in transition between rain forest and ironstone outcrops vegetation, known as Canga vegetation ( Secco & Mesquita 1983). Besides this a single plant was photographed in 18 November 2014 at “trilha lagoa da mata” at 6º 02’ 43” S, 50º 04’ 59”W growing in the forest. It flowers between October and November.

Pedicel elongation with the development of the fruits seems to be a strategy to disperse seeds a little further from the parent plant.

Conservation status: — The species is known from a conservation unit (Carajás National Forest), which belongs to a mosaic of national conservation units of about 8,073 km ², but its grows over leaf litter in the transition mainly between rain forest and ironstone outcrops vegetation close to an active mine, therefore the species endangered of becoming extinct in the wild in the near future if no action is taken. Data Deficient (DD) according to IUCN (2014).

Etymology:— The epithet refers to the length of the pedicel.

Aditional specimen examined (paratype):— BRASIL: Pará: Parauapebas, Carajás Range, N5 Leste , 12 November 1998, A. Cardoso 722, 723, 724, 725, 726, 727, 728 ( IAN 168.903 to IAN 168.909 ) ; Curionópolis, Serra Leste , October 2006, 510 m, A. Cardoso & J. B. F. da Silva 1182 ( MG) .

Figures

FIGURE 1. Uleiorchis longipedicellata A.Cardoso & Ilk.-Borg A. Habit in flower; B–C. Habit growing fruits; D. Habit riped fruits; E. Flower lateral view; F. Flower front view; G. Perianth extended, adaxial view; H. Perianth extended, adaxial detail of the apex; I. Lip extended, adaxial view; J. Bracts; K. Collumn adaxial view; L. Collumn abaxial view. Illustrated by Alex Araujo (from A.cardoso 721, 724, 725, 727 at IAN).

FIGURE 2. Uleiorchis longipedicellata A.Cardoso & Ilk.-Borg A. Habit in bud and growing fruits; B. Flower front view; C Habit in situ; D. elongated pedicels and mature fruits (Photographs by J.B.F. da Silva).