Novelties in the Pleurothallidinae (Orchidaceae) for the Venezuelan Flora

Abstract

Two new species, Pleurothallis phoenicoptera and P. steinbuchiae, are described. Pleurothallis delascioi is synonymized under P. kerrii. Several other members of the Pleurothallidinae are recorded for the first time for Venezuela. During the course of our studies on the Venezuelan orchid flora for several floristic projects, including the Flora of the Venezuelan Guayana, the following species, previously unrecorded within the country's boundaries, were detected. Lepanthes spelynx Luer & Escobar, Amer. Orchid Soc. Bull. 54: 586. 1985. Among several other Lepanthes species recently collected in Andean Venezuela, this taxon is a new record for Venezuela. Specimen examined. VENEZUELA. Merida: cloud forest at La Montania study area, ca. 0.5 km S of La Montana Teleferico Station, 2,450-2,650 m, 26 Sep. 1987, D. L. Kelly 9100 (K, VEN). Pleurothallis archidiaconi Ames, Sched. Orch. 9: 29. 1925. TYPE: Trinidad-Tobago. Trinidad: Verdant Valley, 11 Dec. 1924, Hombersley s.n. (holotype, AMES). Pleurothallis archidiaconi Ames is widespread in the northern Amazon Basin, the Guayana Highlands, the Coastal Range of Venezuela, TrinidadTobago, and along the lower elevations of the eastern Andean foothills in Venezuela at 50-1,300(-1,500) m. Although similar to many other species in the Macrophyllae-Fasciculatae, Pleurothallis archidiaconi is characterized by its shallowly cordate, NOVON 4: 86-93. 1994. apically acuminate leaf, a 3-nerved dorsal sepal, 57 mm long, subequal or somewhat narrower than the synsepal, relatively broad, oblong petals with serrate or denticulate margins and obtuse to acute apices. The labellum is broadly ovate to broadly ovate-oblong, convex above the middle, and the apex is obtuse to rounded. The margins of the labellum are microscopically erose. The corners at the base of the labellum are distinctly angled to either side of the concavity, which accommodates the column foot. In some populations, the margins of the labellum are somewhat incurved in the middle part making the labellar outline pandurate in natural shape. The flower color varies from dark red in the Venezuelan Guayana and Coastal Range to yellowbrown with darker brown or reddish nerves in most other populations, including the typical one from Trinidad; all color combinations may be present in some populations. The plants are average sized for the Macrophyllae-Fasciculatae. Although collected many times, especially in Venezuela, the species has frequently been misidentified. Forms of the species with incurved labellar margins have been collected in Surinam (photographed by Werkhoven, 1986: 181, as P. monocardia Reichenbach f.) and in some areas of the Venezuelan Guayana, from where it was misidentified as Pleurothallis stenocardium Schlechter by Foldats (1970: 418). Pleurothallis stenocardium is a species from higher elevations in the Guayana Highland tepuis with smaller flowers and different perianth segments. The Venezuelan material from the Coastal Range and the Andes has been identified by Dunsterville & Garay (1959: 337) and by Foldats (1970: 345) as Pleurothallis monocardia, a Colombian Andean species with differThis content downloaded from 207.46.13.11 on Mon, 17 Oct 2016 05:19:30 UTC All use subject to http://about.jstor.org/terms