Consumo De Alimento Por Um Gafanhoto Neotropical, Stenacris Fissicauda Fissicauda (Bruner, 1908) (Orthoptera:Acrididae) Da Várzea Amazônica

Abstract

Average leaf consumption of the grasshopper species Stenacris f. fissicauda is determined. The results are expressed as grams of leaf biomass/gram dry weight grasshopper/ day. The material used in the experiments was collected on Ilha de Marchantaria (island of "várzea \' - Rio Solimões) near Manaus. The animals were grouped accoding to nymph stage (initial (l+ll), middle (III+IV), final (V+VI)), and sex (males, females, males+females). The plant used as food was Paspalum repens, an aquatic macrophytc of the Poaceae on which Stenacris f. fissicaudadevelops its life cycle. The initial stage nymphs consumed the most (0.7740 g/g of animal bio-mass/day), while the smallest consume of leaf biomass was done by adults (0.2622 g/g of animal biomass/day). The calculated average consumption was about 0.5 g (dry weight) of leaf biomass consumed per gram (dry weight) of animal biomass/day. Data are compared with leaf consumption of Cornops aquatietun (Acrididae) on Eichiiornia crassipes (Pontederiaceae) from the same area.