RESUMEN
OBJECTIVE@#To investigate the larvicidal activity of essential oil and methanol extract of the Nepeta menthoides (N. menthoides) against main malaria vector, Anopheles stephensi (An. stephensi).@*METHODS@#The essential oil of plant was obtained by Clevenger type apparatus and the methanol extract was supplied with Percolation method. Larvicidal activity was tested by WHO method. Twenty five fourth-instar larvae of An. stephensi were used in the larvicidal assay and four replicates were tested for each concentration. Five different concentrations of the oil and extract were tested for calculation of LC(50) and LC(90) values.@*RESULTS@#The LC(50) and LC(90) values were determined by probit analysis. LC(50) was 69.5 and 234.3 ppm and LC(90) was 175.5 and 419.9 ppm for the extract and essential oil respectively.@*CONCLUSIONS@#According to the results of this study methanolic extract of plant exhibited more larvicidal activity than essential oil. This could be useful for investigation of new natural larvicidal compounds.