Abstract

Although state Reserves play a major role in biodiversity conservation, private Reserves may play a complementary role by increasing surface and ecological representation. The Reserva Biologica Huilo Huilo occupies an area of 100 000 ha and is situated in the temperate austral forest ecoregion of South America and includes Nothofagus forests and various types of high Andean vegetation. The Reserve is located at Region de Los Rios, near the locality of Neltume (39 degrees 51'S-71 degrees 57'W) at 500 - 2000 m altitude. The results reported were obtained within an area of 11 x 20 km. Specific richness was 406 of vascular plant species belonging to 95 families and 230 genera. The richest families were asteraceae (60 species, 14.8%), poaceae (43 species, 10.6%), cyperaceae (21 species, 5.1%) and hymenophyllaceae (16 species, 3.9%). the richest genera were Hymenophyllum (13 species), Carex and Senecio (9 species each). Alien species constituted 16.3% of the total and native species 83.7%, of which 79 % are endemic to Chile and Argentina and 6 % only to Chile. The Chilean endemics with most restricted distributions are Elaphoglossum fonkii (Lomariopsidae, Pteridophyta) exclusive of Regiones de Los Rios and de Los Lagos, and Ercilla syncarpellata (Phytolaccaceae) from Region de La Araucania, de Los Rios and de Los Lagos. Primula comberi (Primulaceae) and Oenothera stricta var. altissima (Onagraceae) are reported as a new species for Chile. We report for the first time Trichomanes exsectum at the cordillera de los Andes; Ranunculus hydrophilus is mentioned for the first time at Region de Los Rios; finally distribution areas were enlarged for Epilobium densifolium (a new southern limit in Chile) and Lycopodium alboffii (a new northern limit in Chile). Hemilcryptophyta is the richest taxon with Raunkiaer's life form (60 %), followed by macrophanerophyta (11.3%) and nanopanerophyta (11 %). Eighteen species are classified as threatened, most notably Greigia pearcei (Bromeliaceae), Elaphoglossurn fonkii (Lomariopsidaceae), Fascicularia bicolor (Bromeliaceae), Libertia tricocca (Iridaceae) and Trichomanes exsectum (Hymenophyllaceae). About 82.3 % of plant families and 77 % of the genera of the austral temperate South American forest are represented at Reserva Biologica Huilo Huilo. Genera of the Pteridophyta and Magnoliopsida s.l. are the best represented with 82.6% and 76 %, respectively. The Valdivian type forest is the richest community (136 species), followed by Nothofagus dombeyi forest (96 species), Nothofagus antarctica forest (45 species) and Nothofagus pumilio forest (34 species). The Valdivian type forest, although occupying a relatively small area is that with the highest species richness.