larvae are salt water tolerant, preferring concentrations between 10 and 20 parts per thousand (ppt). The larvicidal efficacy of two formulations of Bacillus thuringiensis var
(Vectobac-12AS® and Bactivec®), was investigated against An. aquasalis at salinities of 0, 10, and 20 ppt. A probit analysis was used to calculate the lethal concentrations (LC50
) for each product at each salinity. The LC50
were higher for Bactivec® than Vectobac-12AS®, and for Bactivec®, the LC50
increased with salinity. Vectobac-12AS® should thus be preferred to Bactivec® for An. aquasalis control, especially in saline breeding habitats.