Ultrastructure of antennal sensilla of Erannis ankeraria Staudinger (Lepidoptera: Geometridae).

Abstract

Erannis ankeraria Staudinger, 1861 (Lepidoptera: Geometridae) is one of the major pests causing serious damages on Larix spp., Quercus L., and Picea Mill. To investigate the conceivable functions of antennal sensilla associated with pheromone detection, we observed the ultrastructure of antennae in female and male of E. ankeraria moths by scanning electron microscopy. Six types (including two subtypes and a new type) of sensilla were recorded and characterized, including Sensilla trichodea (ST I and ST II), Böhm bristles, Sensilla squamiformia, Sensilla chaetica, Sensilla auricillic (SAU) and newly observed serrate-like sensilla. ST I and SAU were abundant on male antennae, displaying a sexual dismorphism. Serrate-like sensilla were also peculiar to male antennae. In summary of reported functions of corresponding sensilla, we presumed putative functions of the recorded sensilla in E. ankeraria, providing the morphological basis for sensory mechanisms related to pest management.