Abstract: 【Aim】 This study aims to observe the morphological characteristics of different ages and wing types of Macrosiphoniella sanborni and the ultrastructure of its antennal sensilla, so as to provide a reference for identification of different ages and a basis for study on the sensillal function and odour recognition mechanism of M. sanborni. 【Methods】 The whole-body morphology and ultrastructure of antennal sensilla of M. sanborni were observed under super-depth microscope and scanning electron microscopy (SEM), and the amount, distribution and size of antennal sensilla were statistically and comparatively analyzed. 【Results】 The results revealed that the qualitative indexes such as the wing bud, the projection angle of the end of abdomen and cauda can be utilized for accurate age identification of M. sanborni. Cauda shape can be used to distinguish adults from nymphs. The 3rd and 4th instar apterous nymph don’t have wing bud, while the alatae have. Wing bud shape can be used to distinguish alatae at the 3rd and 4th instars. Projection angle of the end of abdomen can be used to distinguish apterate at the 3rd and 4th instars. The antenna of M. sanborni is of the filiform type, contains five segments in the 1st and 2nd instars, and six segments in the rest. Five morphologically unique sensilla types were found and described: placoid sensillum, coeloconic peg, trichoid sensillum type I, trichoid sensillum type II and campaniform sensillum. Nymphs are different from adults in antennal segments, sensilla types and sensilla amounts. Differences also exist in the type, amount and array
of sensilla on the antennae between alatae and apterae. 【Conclusion】 Different types of M. sanborni can be identified accurately by morphological indexes such as wing bud, projection angle of the end of abdomen and cauda. The antennal sensilla of different ages and wing types of M. sanborni differ in types, numbers and distribution positions, which may directly affect their behavioral performance on locating host plants.

Key words: Macrosiphoniella sanborni, morphology, antenna, sensilla, ultrastructure; scanning electron microscopy