Morphology and Olfactory Recognition of Leg Sensilla in Honeybee Workers of Apis cerana cerana.

Apis cerana cerana is a key social insect, and its ability to recognize chemical signals is crucial for maintaining colony homeostasis and coordinating collective behaviors, such as foraging, nursing, and defense. The legs of insects play a significant role in gustatory perception and proximity olfactory perception. In this study, the leg sensilla of A. c. cerana were observed by scanning electron microscopy (SEM). Two types of sensilla were observed, including sensilla trichodea (Str I, Str II, Str III, Str IV, Str V, and Str VI) and sensilla chaetica (Sch I, Sch II, and Sch III). The two unique structures of the tibial spur (Tsp I, Tsp II) and antennal brush (Abr) are carefully observed. The electrophysiological responses of workers at different ages to diverse chemical compounds were measured via electrolegogram (ELG) recordings on their legs. The results showed that 1-day-old A. c. cerana was more sensitive to nonanal; 10-day-old and 25-day-old A. c. cerana were more sensitive to ocimene. The results of behavioral responses showed that nonanal and ocimene can significantly attract 10-day-old workers of A. c. cerana. This study establishes a foundation for further exploration of the mechanisms by which the legs of A. c. cerana facilitate colony-level communication through chemical signals. It also provides an important theoretical basis for understanding their social organization and information transmission.