Drosophila suzukii is a serious horticultural and quarantine pest, damaging various berry crops. Although the active use of olfactory communication in D. suzukii is well-known, their olfactory sensory system has not been comprehensively reported. Therefore, the present study was carried out to understand the morphology, distribution and ultrastructure of olfactory sensilla present in the antennae and maxillary palps of D. suzukii, through scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The olfactory sensilla on the antennae of D. suzukii in both sexes could be classified into three major morphological types, basiconic, trichoid and coeloconic sensilla, according to their shapes. The antennal basiconic sensilla were further divided into three subtypes and the antennal trichoid sensilla into two subtypes, respectively, according to the size of individual sensillum. In contrast to the antennal olfactory sensilla showing diverse morphology, basiconic sensilla was the only type of olfactory sensilla in the maxillary palps of D. suzukii. The basiconic sensilla in the maxillary palps could be further classified into three subtypes, based on their size. Our SEM and TEM observations indicated that multiple nanoscale pores are present on the surface of all types of olfactory sensilla in the antennae and maxillary palps, except coeloconic sensilla. The difference in the morphological types and the distribution of olfactory sensilla suggests that their olfactory functions are different between antennae and maxillary palps in D. suzukii. The results of this study provide useful information for further studies to determine the function of olfactory sensilla in D. suzukii and to understand their chemical communication system.

铃木果蝇是一种严重的园艺和检疫性害虫，损害了各种浆果作物。虽然在铃木D.中积极使用嗅觉交流是众所周知的，但尚未全面报道其嗅觉感觉系统。因此，本研究旨在通过扫描电子显微镜（SEM）和透射电子显微镜（TEM）了解铃木D.触角和上颌触觉中嗅觉感受器的形态，分布和超微结构。铃木D.触角上的嗅觉感受器根据它们的形状，可以将两种性别分为三种主要的形态类型，即基本型，毛发型和腔圆锥形感官。根据单个感官的大小，将触角感神经感觉器进一步分为三种亚型，触角毛发感器进一步分为两种亚型。与触角嗅觉感受器呈现出不同的形态相比，在铃木D.上颌中，碱性神经感受器是唯一类型的嗅觉感受器。。上颌触觉中的碱性神经感觉器可根据其大小进一步分为三种亚型。我们的SEM和TEM观察表明，触角和上颌触觉中，除腔管性感器外，所有类型的嗅觉感器的表面均存在多个纳米级的孔。嗅觉感觉器的形态学类型和分布的差异表明，铃木中触角和上颌触觉的嗅觉功能是不同的。这项研究的结果为进一步研究确定嗅觉感官在铃木中的功能以及了解其化学通讯系统提供了有用的信息。