Levantamento do número de espécies de dicotiledôneas da Amazônia legal depositadas no herbário MG (Museu Paraense Emílio Goeldi)

Abstract

Estimates of the number of species of Amazonian flora are very divergent, ranging from 18,000 to 60,000, according to some authors. However, information that is closer to reality is largely available in regional herbaria, requiring only a detailed survey to answer this question. The present work is a contribution to the knowledge of the number of species in the Amazon, emphasizing initially the dicotyledons, because they are the most representative group in the region, in an attempt to obtain a more realistic estimate of the plant resources available in the Amazon domain. A survey of the species of the Legal Amazon deposited in the MG herbarium was done, comparing the list with the "check-list" of the INPA herbarium, and the species that were not on the master list were added; some families were worked from the database of the BRAHMS Informatization Program. To date, a total of 6,151 species have been collected, distributed in 91 families (from a total of 161) of dicotyledonous plants. The families with the greatest number of species were Leguminosae (1,100), Euphorbiaceae (264), Melastomataceae (400), Lauraceae (276), Apocynaceae (243), Moraceae (230) and Myrtaceae (173). Comparing these results with those from the INPA and IAN herbaria, we found a greater richness of dicot species in the MG herbarium, in relation to the families Leguminosae, Melastomataceae, Moraceae and Apocynaceae.