Ultrastructural characterization of sensilla and microtrichia on the antenna of female Haematopota pandazisi (Diptera: Tabanidae)

The haematophagous females of the cleg fly Haematopota pandazisi (Kröber) (Diptera: Tabanidae) are a common pest in areas inhabited by wild and domestic ungulates in southern Europe, North Africa and Anatolia. A morphological investigation by scanning electron microscopy (SEM) was carried out for the first time on the antennae of females of H. pandazisi, with special attention to the type and distribution of sensilla and microtrichia. The typical brachyceran antenna is divided into three regions: the scape, the pedicel and the flagellum, which is the longest of the three and is composed of four flagellomeres. The scape and pedicel are characterized by only one type of microtrichium and chaetic sensillum, whereas five types of microtrichia and sensilla were identified on the flagellum and classified according to shape and distribution. The sensilla are of the chaetic, clavate, basiconic, trichoid and coeloconic types; the latter with either a basiconic or grooved peg inside. The results obtained in this study were compared to those found in other species in the family Tabanidae and other Diptera, with special attention to haematophagous species.