The ultrastructure of "sex segments" of male antennae have been studied in two diapriids representative of the subfamily Diapriinae, Trichopria drosophilae and Coptera occidentalis using scanning and transmission electron microscopes. T. drosophilae has one modified antennomere (A4) bearing a carina while C. occidentalis bears a peg-like process on A3 and a carina on A4. In both species all these external structures can be considered as release structures, being associated with epidermal glands. The glandular complexes of both species are formed by bicellular units composed of a class 3 secretory cell and a canal cell. Ultrastructural observations did not reveal noticeable differences in cytological features of the three glands. Moreover, C. occidentalis male antennal glands are provided with structures to store the secretion. They consist of a large reservoir in the A3 glandular complex and of a small bulb-like reservoir in each of the secretory units in the A4 gland. All the release structures were found to be covered by an abundant and viscous thread-like secretion. The possible involvement of male antennal glands in sex recognition and the diversity in the skeletal morphology of sex segments in other diapriids are shown and discussed.
External morphology and ultrastructure of male antennal glands in two diapriids (Hymenoptera: Diapriidae)
ROMANI, Roberto;
1999
Abstract
The ultrastructure of "sex segments" of male antennae have been studied in two diapriids representative of the subfamily Diapriinae, Trichopria drosophilae and Coptera occidentalis using scanning and transmission electron microscopes. T. drosophilae has one modified antennomere (A4) bearing a carina while C. occidentalis bears a peg-like process on A3 and a carina on A4. In both species all these external structures can be considered as release structures, being associated with epidermal glands. The glandular complexes of both species are formed by bicellular units composed of a class 3 secretory cell and a canal cell. Ultrastructural observations did not reveal noticeable differences in cytological features of the three glands. Moreover, C. occidentalis male antennal glands are provided with structures to store the secretion. They consist of a large reservoir in the A3 glandular complex and of a small bulb-like reservoir in each of the secretory units in the A4 gland. All the release structures were found to be covered by an abundant and viscous thread-like secretion. The possible involvement of male antennal glands in sex recognition and the diversity in the skeletal morphology of sex segments in other diapriids are shown and discussed.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
