The forewing of the Aphis fabae (Scopoli 1763) (Hemiptera, Sternorrhyncha): a morphological and histological study

Abstract

Dorsal and ventral sides of the forewing of Aphis fabae (Scopoli 1763) (Sternorrhyncha, Hemiptera) were examined by scanning electron microscopy. Reinforcement elements on their surface as well as scale-like elements were described. Using histological methods, cross-sections of the material were done. They showed a two-layered membrane with a circular foramen inside. The course of veins and places of their bifurcation were followed. Common stem of radius (R), media (M), and cubitus anterior (CuA) veins were composed of separate tracheae, which ran separately at the beginning, then continued in a single tunnel, and finally disappeared. Nerves were not observed. Neither were tracheae visible on the further course of those veins. The presence of a devoid-of-trachea costal vein was confirmed. Under scanning electron microscope, convex reinforcements on dorsal side of the wing turned out to be more sclerotized parts of chitin, not giving a zigzag-like profile of the wing on sections. In this paper, we show for the first time a cross-section of a very delicate wing of an aphid representative.

Keywords: Aphids; Cross-section; Forewing; Tracheae; Wing veins.

Fig. 1

Scanning electron microscopy showing the forewing of Aphis fabae (Scopoli 1763), places of sectional cuts

Fig. 2

Scanning electron microscopy showing the forewing of Aphis fabae (Scopoli 1763), veins organization, dorsal view

Fig. 3

Scanning electron microscopy showing part of the wing of Aphis fabae (Scopoli 1763), with pterostigma (pt) a dorsal view, b ventral view; white arrows indicate reinforcement elements; white asterisks indicate scale-like elements

Fig. 4

Scanning electron microscopy showing apical part of the wing of Aphis fabae (Scopoli 1763) a dorsal view, b ventral view, white arrows indicate reinforcement elements; white asterisks indicate scale-like elements

Fig. 5

Scanning electron microscopy showing the wing of Aphis fabae (Scopoli 1763) a apical part of media vein (M₃₊₄), dorsal view, b apical part of first branch of cubitus vein (CuA₁), dorsal view, c part of common stem and both branches of cubitus vein (CuA₁, CuA₂), dorsal view; white arrows indicate reinforcement elements; white asterisks indicate scale-like elements; scale bar 100 µm

Fig. 6

Cross-sections of the forewing of Aphis fabae (Scopoli 1763) under magnification a–c ×40, d ×20; LM light microscope, c cuticle, e epidermal cells. SEM scale bar 0.5 mm

Fig. 7

Cross-sections of the forewing of Aphis fabae (Scopoli 1763) under magnification a–f ×10; LM. SEM scale bar 0.5 mm

Fig. 8

Cross-sections of the forewing of Aphis fabae (Scopoli 1763) under magnification a–f ×10; LM. SEM scale bar 0.5 mm

Fig. 9

Cross-sections of the forewing of Aphis fabae (Scopoli 1763) under magnification a and b ×10; c–e ×20; LM. SEM scale bar 0.5 mm