Electron microscope study on workers antennae and sting lancets of three subspecies of honey bee Apis mellifera L. (Hymenoptera: Apidae) and its bearing on their phylogeny

Abstract

Ultrastructure of antennae and sting of the honey bee workers in three subspecies of Apis mellifera; Egyptian A. m. lamarckii, Carniolan A. m. carnica and Italian A. m. ligustica was investigated. Twelve types of sensilla were recorded on the worker antennae; placodea, basiconica, trichodea types (A, B, C and D), ampullaceal, coeloconica, coelococapitular, non-innervated hair seta, campaniformia and sensilla chaetica. The latter is recorded for the first time on antennae of A. mellifera. The number and distribution of the various types of sensilla are recorded. Sensilla trichodea were found most frequently and were present on all the antennal segments. Sensilla placodea were present on the distal eight flagellomeres. Sensilla ampullaceal and sensilla coeloconica were present on the distal five while sensilla campaniformia were confined to the distal seven flagellomeres. The barbs carried on the lancets of sting differ in numbers among the workers of the three subspecies; 10, 9 and 7 in A. m. lamarckii, A. m. carnica and A. m. ligustica, respectively. Depending on morphometrical analysis, a dendrogram separated the Egyptian subspecies from the other two subspecies with a highly genetic distance of 0.25 between them. The Italian and the Carniolan subspecies were grouped into one main cluster with a genetic distance of 0.01 between them.