The biology of the bromeliad-eating weevil Metamasius mosieri Barber (Coleoptera: Dryophthoridae) was studied under laboratory conditions of 25°C, 50–60% RH, and a photoperiod of 14:10 (L:D) h. Mean duration of the egg, larval, and pupal stages was 8.2, 59.6, and 9.7 d, respectively. Mean adult longevity was 36.1 wk for females and 50.2 wk for males. Females produced on average 39.2 eggs during their lifetime. The larval and pupal stages are described, and characters for distinguishing the pupae of M. mosieri and Metamasius callizona (Chevrolat) are contrasted and illustrated. Oviposition behavior is described. The weevil is known to be present in 13 south Florida counties.