Integumental glands associated with tactile hairs on the ovipositor of tephritid flies

The seventh abdominal segment, which forms the oviscape of the ovipositor in the tephritid flies Urophora affinis and U. quadrifasciata, bears setae in two bilaterally symmetrical rows on the dorsal and ventral aspects of its distal margin and scattered irregularly over the rest of its surface. At the anterior side of the base of each hair is a porous plaque covering a channel through the cuticle into which strands of a microtubular "secretory". material extend from the cytoplasm of a greatly enlarged gland cell. One such cell is associated with each hair, which is innervated by a single dendrite that terminates in a tubular body at the base of the hair. These gland cells are absent in male flies. The possible morphologic, functional, and taxonomic significances of these gland cells are discussed.