Aims The overall aim of this study is to provide the data needed for Amazonian conservation and the sustainable management of the region. To this end I model the hypothetical distribution of plant species richness across the Amazon Basin, the distribution of the proportion of this species richness that can be accounted for by described species, and hence the distribution of the biodiversity which remains unknown.Location Amazonia, Neotropics.Methods Species richness across the Amazon Basin is estimated by comparing the occurrences of 1584 species of Magnoliophyta whose taxonomy and geographical distributions are relatively well known. These data are used to collate checklists for squares of 1°latitude by 1°longitude. Comparison of the checklists allows estimation of the relative expected diversity in the vicinity of each degree square. Summing the distributions of the hypothetical real ranges gives the proportion of the biodiversity that can be accounted for by described species. Subtraction of the second distribution from the first gives a distribution of the contribution to the overall biodiversity that the model predicts, potentially, results from as yet undescribed species. ResultsCollections documented in recent botanical monographs show an extremely biased distribution with the best knowledge being found in a very few relatively well-collected areas. At the degree square level, this model predicts that gamma biodiversity in the Amazon Basin is uniformly high across most of the basin. The model predicts that four large areas of the basin are particularly poorly known, and that they should contain large numbers of uncollected species. Main conclusionsThe model presented here highlights the difficulties of quantifying Amazonian plant diversity and its distribution. The low density of collections, and especially their extremely clumped distribution, undermines confidence in theories that seek to explain the apparent distribution of biodiversity. The model's prediction is substantially different from published predictions of the distribution of alpha diversity. Testing of this model in the areas identified as lacunae would require collecting programmes designed to collect fertile material of rare species. If the model's predictions are approximately accurate, the plant biodiversity of the Amazon Basin is considerably underestimated.

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O projeto mostrou que a biodiversidade na Reserva era bem maior do que havia sido estimada anteriormente. São apresentados dados ilustrando a história de exploração botânica na área. Baseando-se na experiência do projeto, são feitas recomendações sobre procedimentos para realização inventário de espécies vegetais em floresta tropical.

One hundred and thirty‐eight scat (faecal) samples from 17 mammal species native to forests of northeastern Queensland were examined for the presence of spores of both ectomycorrhizal and arbuscular mycorrhizal fungi. Spores of mycorrhizal fungi were found in 57 percent of scat samples representing 12 animal species (Aepyprymnus rufescens, Antechinus godmani, Bettongia tropica, Hypsiprymnodon moschatus, Isoodon macrourus, Melomys ceruinipes, Perameles nasuta, Rattus fuscipes, R. tunneyi, Thylogale stigmatica, Trichourur uulperula, Uromys caudimaculatus). Spores were absent in scats of Antechinus stuartii, Dasyurus hallucatus, Dendrolagus lumholtzi, Petaurus australis and Mesembriomys gouldii. Spores of ectomycorrhizal fungi occurred in 38 percent of scats, and all but one of these samples were from Eucalyptus‐dominated sclerophyll forests. Based on the frequency and abundance of spores in scats, five mammals were considered active consumers of hypogeous mycorrhizal sporocarps in sclerophyll forests (A. rufescens, B. tropica, I. macrourus, P. nasuta, and U. caudimaculatus). Individual scats of these animals generally contained a range of distinctive spore types. Spores of arbuscular mycorrhizal fungi were found in low abundance in almost 40 percent of scat samples collected, from both sclerophyll forest and rainforest habitats. We suggest that the majoriry of these spores were acquired incidentally through ingestion of soil during foraging activities on the forest floor. Glasshouse inoculation experiments in which seedlings of Eucalyptus grandis and Sorghum bicolor were inoculated with scat material from several species of mammal demonstrated that the spores of ectomycorrhizal and arbuscular mycorrhizal fungi retained some viability and colonized the roots of host‐plant seedlings. Insufficient information is known of the ecology of mycorrhizal fungi in Australia's tropical forests to speculate as to the implications of these findings for forest conservation and rehabilitation.

Canopy observations of the rain forest tree Parkia velutina (Leguminosae: Mimosoideae) in Amazonian Brazil indicate that it is pollinated by night-flying bees. The small red flowers are organized into spherical heads; they open in the late afternoon and attract Megalopta bees (Halictidae: Augochlorini) which forage for pollen after dark. In contrast to the numerous bat-pollinated species of Parkia, no nectar was detected. Nocturnal melittophily is proposed as a possible intermediate stage in the evolution of chiropterophily from diurnal entomophily in Parkia.