摘要
The venom apparatus in the large carpenter bees, Xylocopafenestrata （Fabricius） （Hymenoptera： Apidae） has been studied It consists of typical parts, i.e., the venom sac, free filament, Dufour gland, sting shaft and accessory sclerites. It is highly sclerotized and concealed by the 7th abdominal tergite and sternite. The venom sac serves as a reservoir for the venom which synthesized by the convoluted gland present in it, which is remarkably uniform to that of ants. The median duct extends from lower portion of venom sac, which measures 2.5 ±0.17 mm （mean ＋ SD） （n = 20） in length. The Dufour gland is a tube-like structure which is inserted in the sting-bulb. The triangular plate is attached at terminal portion of rami, which is in turn attached with lancets. The gonostyli are paired long and tubular structure with 5.29 ± 0.23 mm （n = 20） in length. The sting length is 5.29 ±0.23 mm （n = 20）. The fulcral arm is well-developed with an inverse Y-shaped structure present beneath the sting-bulb. Barbs on the sting shaft are weakly developed in X fenestrata but well developed in ants. The venom apparatus ofX. fenestrata when compared is similar to the bees but differs from that of the wasps and ants.
