Scanning Electron Microscopy of the Proboscis and Associated Sensilla in Colias erate (Esper, 1805) (Lepidoptera: Pieridae)

Morphological studies of the proboscis can provide valuable insights into the evolutionary adaptations of Lepidoptera. However, such research is relatively limited for Pieridae, a family that is significant both ecologically and economically. In this study, scanning electron microscopy (SEM) was employed to investigate the proboscis and associated sensilla of adult <i>C. erate</i>, with an emphasis on ultrastructural details and potential sex-specific differences. The proboscis in both sexes exhibits a similar structure, consisting of two elongated maxillary galeae connected by dorsal and ventral legulae. It is divided into three distinct zones based on morphological changes in the dorsal legulae. The outer surface of the proboscis is characterized by spike-like microbumps on transverse ridges, while the inner surface (food canal) is smooth throughout all three zones, with regularly spaced transverse grooves. Three types of sensilla comprising five subtypes were identified: sensilla chaetica (sc), sensilla basiconica (sb1, sb2, and sb3), and sensilla styloconica (ss). The functional implications of these morphological features are also discussed briefly.