The eversible membrane is the mostly membranous middle section of the ovipositor. It is between the ovicape and the aculeus, and it and the aculeus can be retracted into the oviscape. If it is not everted, the terminalia must be dissected to examine the eversible membrane. Subbasally on the dorsal side in Anastrepha and Toxotrypana, the eversible membrane bears a group of denticles of which at least some usually are large, sclerotized, and hooklike. Opposite these denticles on the ventral side the membrane usually bears only minute, simple denticles.