APPLICATION OF THE OVARIAN OIL INJECTION AND OVARIOLAR SEPARATION TECHNIQUES FOR AGE GRADING HEMATOPHAGOUS DIPTERA

The ovarian oil injection and ovariolar separation techniques were app lied to determine the physiological age of species of tie 3 dipteran f amilies Culicidae, Simuliidae, and Tabanidae. The presence of a granul ar basal body (a granular area in tile calyx wall within the ovariolar sheath) indicates at least 1 egg laying; that is, it cim be used to s eparate parous from nulliparous females, which possess no granular bas al body. In parous females, the number of ovipositions can be determin ed accurately by counting the number of dilatations in the diagnostic ovarioles. An egg sac, when present, indicates only the current egg la ying. A diagram for age grading using the technique is presented and d iscussed.