关键词: 家蝇, 产卵器, 足, 感受器

Abstract:

Objective　To analyze the morphological characteristics of the receptors on ovipositors and legs related to the selection of oviposition substrates in female houseflies. Methods　Ultrastructural observation of ovipositors and legs of female houseflies was performed under a scanning electron microscopy. Results　Six receptors of different morphologies were found on the ovipositors and legs of female houseflies, including bristle sensilla, styliform sensilla, trichoid sensilla, basiconic sensilla, cavity sensilla and coeloconic sensilla. Among them, they were mostly presented on bristle, styliform and trichoid sensilla, followed by basiconic, cavity and coeloconic ones. The bristle sensilla formed a large angle between its stretch direction and the surface. Segmentation of the surface junctional membrane of trichoid sensilla could be seen or not. The length of the styliform sensilla on the 5th  abdominal  segment  was  300-700 μm,  while  those  on  the  legs  no  more  than 120 μm. The  basiconic  sensilla  under the hypopygium were inserted in the cotyloid cavity, the ends slightly thin and blunt; and those on the hindtarsus did not have such basal cavity, suddenly tapering at the ends. In the tibial base of the mid legs there were cavity sensilla?intensive areas. At the end of the left cerci was a coeloconic sensillum. Conclusion　It is implied that houseflies regulate their oviposition behaviors according to the mechanical and humidity information of oviposition substrates detected by the sensitization of these sensilla.

Key words: Musca domestica, Ovipositor, Leg, Sensillum