The weevilTrichobaris bridwelliBarber is a natural enemy of jimsonweed (Datura stramoniumL.) in the southern United States. The temporal distribution of all life stages showed thatT. bridwelliis bivoltine in central Texas and overwinters principally in the adult stage inside the seed capsules of jimsonweed. Females oviposited in the leaves, flowers, and capsules. Subsequent development occurred both in the stems and capsules of its host plant. All life stages ofT. bridwelliwere attacked by hymenopterous parasitoids;Anaphessp. andMicroctonussp. are new host records. In the laboratory, adult females lived an average of 16.1 wk and deposited an average of 324 eggs. Development in the laboratory required 37.8 d: egg 5.9 d, larval stage 20.2 d, prepupal period about 3 d, and pupal stage 8.7 d. The intrinsic rate of increase (Tm) ofT. bridwelliwas calculated from laboratory life table data to be 0.41 at 24°C.T. bridwelliwas evaluated for its potential effectiveness as a biological control agent of jimsonweed and possibly chinese thornapple,Datura feroxL. AlthoughT. bridwellidid not complete development on a critical test plant (tobacco) under laboratory conditions, extensive host specificity testing should be conducted to determine the limits of its host range.