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Zusammenfassung:
Six palms of the species Attalea phalerata Mart. (Arecaceae) were sampled during the high water season of the Mato Grosso Pantanal (February 2001), in order to analyse their composition and diversity, estimate the biomass of the arthropod community associated with the canopies of this plant species, and to investigate the influence of the flood pulse on this community. This study was carried out in the region of Pirizal, in the municipality of Nossa Senhora do Livramento, at the Retiro Novo Ranch in the Pantanal of Poconé, Mato Grosso, in areas where this plant species grows together in what are know locally as “acurizais”. The method of collection employed, canopy fogging, involves the application of an insecticide which is sprayed on the canopies using a non-residual, synthetic pyrethroid, Lambdacialotrina (1%), associated with the synergist DDVP (0,1%) and applied from the ground over the whole of the canopy with the aid of a thermobilizer SWINGFOG SN50. The spray was applied at 6.00am and the arthropods were collected in nylon funnels of a diameter of 1m positioned under the canopy and which contained plastic sample collectors containig 92% alcohol. Each tree was sprayed once, followed by three consecutive collections. The first, two hours after spraying, the second, two hours after the canopy had been shaken vigorously and the third, after cutting off all the leaves and washing off any arthropods still stuck on the leaves. In the laboratory all the specimens collected were identified according to the level of the taxonomic order, species of Coleoptera by the level of the family and morphospecies (recognisable taxonomic units). Also, samples of Formicidae and Araneae were sent to specialists for identification of the family and species. A total of 63638 arthropods (642,8 ± 259,7 ind/m2), distributed between the Classes Insecta, Arachnida, Diplopoda and Crustacea and 25 orders, the most dominant groups being those of Acari, Coleoptera, Psocoptera, Diptera, Collembola and Hymenoptera the majority being Formicidae. From the Coleoptera group a total of 7670 specimens obtained, including larvae, of wich there were 48 families and 467 morphospecies. Endomychidae, Nitidulidae, Tenebrionidae, Staphylinidae and Phalacridae were the most dominant families. Staphylinidae, Curculionidae, Tenebrionidae and Chrysomelidae had the largest groups of morphospecies. In relation to the Formicidae, a total of 6 subfamilies, 13 tribes and 29 species were obtained. The Araneae consisted of 20 families with Salticidae and Araneidae being the most abundant. The biomass corresponded to 8.86g of dry weight and 0.18 mg/m2. Coleoptera, Blattodea, Orthoptera, Araneae and Hymenoptera were the most representative groups and Scarabaeidae, Tenebrionidae, Alleculidae, Nitidulidae and Curculionidae were the families of Coleoptera with the greatest biomass
