Ultrastructural observations on antennal sensilla of Massicus raddei Blessig ( Coleoptera: Cerambycidae ).

As part of studies to understand the mechanisms of host and mate selection by adult Massicus raddei Blessig (Coleoptera: Cerambycidae), we used scanning electron microscopy (SEM) to observe and describe the morphology of antennal sensilla on adults of both sexes. We observed seventeen different types of sensilla, seven types of sensilla basiconica, four types of sensilla chaetica, two types of sensilla trichodea, two types of sensilla dentiform, one type of sensilla gemmiformium, and one type of sensilla campaniformia. Differences were observed between males and females: Basiconica Ⅳand chaetica Ⅳ were peculiar to females whereas basiconica Ⅴ, basiconica Ⅵ, basiconica Ⅶ, trichodea Ⅳand campaniformia were found only in males. Antennae of females had more sensilla than those of males, and also had slightly more sensilla on the venter than on the dorsum, differences were insignificant. Differences between sexes in the number, type, and distribution of antennal sensilla on adult M. raddei suggest that males and females may differ in response to certain chemical and physical stimuli in the environment.