Evaluación en laboratorio de la toxicidad aguda de los insecticidas malatión y deltametrina en Chasmagnathus granulata Dana (Crustacea, Brachyura, Grapsidae)

Abstract

Acute toxicity of two insecticides malathion and deltamethrin was studied in adult of the estuarine crab Chasmagnathus granulata. Static tests were performed and the concentration that killed 50% of test organisms (LC50) were estimated. Only adult male crabs (mean carapace width: 20.9 ± 0.73 mm and 33.0 ± 2.94 mm) were used. The toxicity of compounds varied substancially. No significant differences (P> 0.05) were found comparing both carapace. The estimated LC50 values to malathion were 13 ug/1 (11.3-19.0) and 19 ug/1 (15.0-26.0) respectivily. The estimated LC50 values to deltamethrin were 0.27 ug/1 (0.25-0.45) for both measure of carapace used. Chasmagantkus granulata was more tolerant to malathion than deltamethrin.