Ultrastructure of antennal sensilla of four skipper butterflies in Parnara sp. and Pelopidas sp. (Lepidoptera, Hesperiidae)

Most species of Parnara and Pelopidas (Hesperiidae) are important pests of rice. In this study, the antennal morphology, types of sensilla, and their distribution of four skipper butterflies, including Parnara guttata (Bremer & Grey), Pa. bada (Moore), Pelopidas mathias (Fabricius) and Pe. agna (Moore), were observed using a scanning electron microscope. Six distinct morphological types of sensilla were found on the antennae of all of these species: sensilla squamiformia, sensilla trichodea, sensilla chaetica, sensilla auricillica, sensilla coeloconica, and Böhm sensilla. The sensilla trichodea are the most abundant sensilla among the four skipper butterflies, and the sensilla auricillica are confirmed on the antennae of butterflies for the second time. In addition, the possible functions of these sensilla are discussed in the light of previously reported lepidopteran insects, which may provide useful information for further study of the function of these antennal sensilla and for related pests control by applying sex pheromones.