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

Barbara Franielczyk-Pietyra,Piotr Wegierek

doi:10.1007/s00435-017-0358-7

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.

Highlights

Insect body must be resistant to many environmental factors
Dorsal surface of Aphis fabae forewing is characterized by strongly convex reinforcement elements (Figs. 3a, 4a, 5; white arrows), each one covered by ring-like elements
The nomenclature of wing veins in insects should differentiate between true veins and false veins

Summary

Introduction

Insect body must be resistant to many environmental factors. It is especially true in case of wings, in long-distance flying insects (Dirks and Taylor 2012). An insect wing is a two-layer membrane supported by longitudinal veins, sometimes cross-veins and reinforced by extracellular cuticle. Wing veins are described as hollows circular on section, providing hemolymph, nerves and tracheae (Kukalova-Peck 1978; Dudley 2000; Shimmi et al 2014). Tracheae appear in the wing before veins so it seems that they determine the course of the veins. Nerves or hemolymph are not always present in veins. Vein sections can be far from circular—from oval to campanulate (Snodgrass 1935; Dudley 2000), but most popular are dumbbell-shaped (Rajabi et al 2016b)

Methods

Results

Conclusion