Ultrastructure of sensilla on the antennae of Apis mellifera queens

This study aims to clarify the morphology of the antennae and the types and characteristics of sensilla in Apis mellifera queens, update and supplement the more clear photos and sensory information of the antennae of the queen.

The morphology, types and distribution of the antenna and sensilla of the 1-day-old A. mellifera queen was observed and analyzed by scanning electron microscopy.

The results showed that the antennae of the queen were geniculate, consisting of scape, pedicel and flagellum. Scape accounted for approximately one-third of the total antennal length, pedicel was the shortest segment, flagellum was the longest, and could be divided into ten flagellomeres, among which the third to tenth flagellomere had the most abundant sensilla. There were various forms of setae and nine kinds of sensilla on the antennae of the queen. Sensilla placodea was unique to the third to tenth flagellomere. Only the scape had brushy and pinnate setae. The lateral sensilla were more diverse than the medial sensilla, and the medial surface were all covered with scales without sensilla placodea.

It is concluded that the distinct spatial distribution of sensilla types across the antennal segments suggests different types of sensilla may have distinct functions. in A. mellifera queens.