Three New Species of Eleocharis (Cyperaceae) from the Andean Páramos of Colombia and Ecuador

Abstract

INTRODUCTION Scope and geographical coverageThis extract of the PHYSIS database of the Institut Royal des Sciences Naturelles de Belgique offers a framework to organize in an ordered sequence, according to the same methodology as that used for the CORINE Biotopes Habitats of the European Cominunity typology (Devillers et al., 1991), the habitats of the South American realm. The geographical area covered encompasses South America and its nearshore islands, Trinidad and Tobago, Margarita, Aruba, Curaçao, Bonaire, Los Roques, Blanquilla and associated islands, the Galapagos Islands, Malpelo Island, the Juan Fernandes Islands, the San Felix archipelago, Fernando de Noronha, South Trinidad and the Martin Vas islands, St. Peter and St. Paul rocks, Easter Island and Sala y Gomez.Definitions and structure 1. Habitat.In the most common usage, a habitat is "the natural home of an animal or plant" (Collins English Dictionary), "the normal abode or locality of an animal or plant" (Chambers Twentieth Century Dictionary), or "the natural abode of a plant or animal" (Webster's New Collegiate Dictionary). Integrating these definitions over all species, for each of which the habitat is the sum of the abiotic enviromnent and of all other species present, a habitat can be defined as "a topographical expanse homogeneous in its physical and biotic components at the scale of the phenomenon studied" (Blondel, 1979(Blondel, , 1995. This is the defînition that has been adhered to in the CORINE Habitat typology and the Physis data-base. Thus, a habitat is a three-dimensional spatial entity that comprises at least one interface between air, water and ground spaces, it includes both the physical environment and the communities of plants and animals that occupy it, it is a fractal entity in that its définition depends on the scale at which it is considered. The conditions encountered by a given species are similar on the entire surface of the habitat, but not all characteristics of the habitat are ever assembled at any one point (Blondel, 1979(Blondel, , 1995. Scale.The définition of a habitat depends entirely on the scale at which it is considered (Blondel, 1979(Blondel, , 1995. Thus a steppe can be defined, as in the Physis Database, as a "formation dominated by medimn or tall perennial tuftforming grasses or suffrutescents, with lacunar ground cover, together with its associated therophyte communities". At a higher level of resolution it can be seen as a mosaic of habitats, bunches of tail perennial grasses on the one hand, bare surfaces temporarily supporting communities of therophytes on the other hand. At a lower level of resolution, the grass steppe and the steppe woods that dot it can be regarded as a single habitat, the wooded steppe. The level of resolution that has been used in the CORINE typology is that of the ecological requirements of small vertebrates, large invertebrates and vascular plants. A few units, clearly labelled, have been introduced to permit rendition by the use of single codes or combined codes of the ecological...