Aprostocetus vaquitarum (Wolcott) (Hymenoptera: Eulophidae) is an ectoparasitoid of Diaprepes abbreviatus (L.) (Coleoptera: Curculionidae). Diaprepes abbreviatus, a root weevil native to the Caribbean, was introduced into Florida in the 1960’s and is now an economically significant pest of several crops including citrus and various ornamentals. Aprostocetus vaquitarum was collected in the Dominican Republic and released in Florida in 2001. It has established in the extreme south-east region of the state resulting in significant Diaprepes egg mortality but to date has not successfully established further north. One possible constraint is the lower temperatures encountered in the central and northern parts of Florida. The influence of temperature on life history traits of this ectoparasitoid was investigated in the laboratory on eggs of D. abbreviatus. Development was most rapid at 25 and 30oC with slower development at 20 and 33oC. Development was not completed at temperatures of 15oC or lower. Oviposition was highest at 30oC, large numbers of eggs were also laid at temperatures of 25 and 35oC; oviposition was significantly reduced at 20oC and extremely low numbers of eggs were laid at 15 or 40oC. The effect of short periods of freezing on different developmental stages of A. vaquitarum was also investigated.