AbstractThe venom apparatus ofChelonusnearcurvimaculatus(Braconidae) has a simple (type 2) morphology. Most of the venom is accumulated in a thin‐walled venom reservoir at the distal end of the gland filament as a 10–17% protein solution. The best results for isolation of the proteins were obtained using 7.5% sucrose in phosphate buffer, pH 7.4. There are four major proteins, with respective Mrvalues of 32,500, 47,000, 53,000, and 131,000. Of these, those of Mr32,500, 53,000, and 131,000 contain carbohydrate. Most of the venom proteins are acidic with pI values between 4.9 and 6.9. The venom does not show proteolytic activity corresponding to serine or thiol proteinases, nor does it show antitrypsin or antichymotrypsin activity. Using immunoblotting techniques, it was established that during parasitization of a single host egg (Trichoplusia ni) about 1/200 of a venom reservoir equivalent is injected. All major venom proteins have been found in stungT.nieggs; thus, no detectable changes in their molecular weight occur during injection or shortly after injection into the h