A suspension concentrate formulation of Bacillus thuringiensis subsp. israelensis (strain SA3A; spore-minus strain of Bti) for control of mosquitoes. The product has a potency of 1200 International Toxin Units (ITU) per milligram against Aedes aegypti larvae. Teknar SC is intended for use in aqueous spray applications to habitats with little or no vegetation. Rates for control of mosquitoes range from 0.25–2 pints/acre (0.3–2.3 liters/ha). Rate selected should be based on habitat, larval population/stage, and/or environmental conditions.