Comunidades de aranhas (Araneae) em cultivos de seringueira (Hevea brasiliensis Muell. Arg.) no Estado de São Paulo

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

The spider fauna composition of three rubber tree commercial plantations in the Northwest part of São Paulo State, Brazil, was characterized for both canopy and litter strata. on seven occasions from April 2000 to October 2001, samples were taken by beating sheet and hand capture, resulting in a total of 946 individuals, belonging to 24 families and 119 species. The most common species were Italaman santamaria Brescovit, 1997 and Teudis sp. (Anyphaenidae), Castianeira sp. and Falconina aff. gracilis (Corinnidae), Paracleocnemis sp. (Philodromidae), Ibotyporanga naideae Mello-Leitão, 1944 (Pholcidae), Chira spinipes (Taczanowiski, 1871) and Rudra sp. (Salticidae), Achaearanea hirta (Taczanowiski, 1873) and Coleosoma floridanum (Banks, 1900) (Theridiidae) and Goeldia sp. (Titanoecidae). Anyphaenidae, Theridiidae and Salticidae were the most abundant families in the canopy, while Pholcidae and Corinnidae in the litter. Spider abundance was found to be, in general, positively correlated to the litter volume and density of branches in the trees. The use of acaricides and insecticides for one plantation resulted in a decrease in spider abundance for both strata. Abundance values among the samples suggest that the canopy spider abundance decreases with the loss of leaves in the dry season. Simultaneously, litter spider abundance increased in this season, because of the increase in litter volume. The most active canopy spiders, like runners and stalkers, should be investigated for their potential as pest control agents.