Sensory Scales Along the Wing Margin of Pieris rapae (Lepidoptera: Pieridae)

Abstract

Abstract The morphology, number, and arrangement of sensory scales along wing margins of the imported cabbageworm, Pieris rapae (L.) (Lepidoptera: Pieridae), were examined by scanning electron and light microscopy, after applying a microscopic operation to the margins. The sensory scales were much more slender than the noninnervated scales, which completely covered the former. The total number of sensory scales was ≈190 and ≈60 in the forewing and hindwing, respectively, and the patterns of sensory scale arrangement differed between the forewing and hindwing and varied from region to region in each wing margin. Sensory scales were densely distributed along the proximal half of the anterior forewing margin and along a fairly small region of the anterior hindwing margin, immediate to the wing base; they were sparsely distributed or absent along other regions of the wing margin. Sensory scale morphology and arrangement were compared with those of the sensory bristle, another kind of hair-like sensilla, and are discussed in terms of wing movement regulation.