OBSERVATIONS ON THE LIFE-HISTORY OF ONTHOPHAGOUS-DEPRESSUS (COLEOPTERA, SCARABAEIDAE)

Adult Onthophagus depressus Harold constructed brood cells of cattle d ung 15 to 30 cm below the soil surface. These brood cells averaged 23. 1 mm long and 16.1 mm wide. Adult females deposited a single egg in th e egg chamber of each brood cell. Eggs were 2.3 to 2.5 mm long and 1.1 to 1.4 mm wide. Embryonic development required 2.5 to 4.3 d; larval d evelopment (three instars) 27 d, and pupal development about 12 d. Dev elopment from egg to adult averaged 46.3 d at 25-27 degrees C. Adult b eetles were captured in all months except February with peak flight ac tivity between 2000 and 2100 h (EST). Overwintering occurred in the ad ult and/or pupal stage in southern Georgia.