5

Types of Textures in Insect Wings and Classification

61

Fig. 5.5 Dragonfly—ventral

view

Example: Mayfly.

Odonata

Dragonflies and damselflies have two pairs of long wings that are almost equal in

size and shape. Membranous wings are thin, long and more or less semi-transparent

(Fig. 5.5). Wings are supported by a system of tubular veins. The wing veins are fused

at their bases and the wings cannot be folded over the body. The main veins and the

cross-veins form the wing venation pattern. There may be very numerous cross-veins

or very few and the wing venation patterns differ. Usually, the abdomen is very long,

and Nymphs or naiads are aquatic.

Examples: Dragonflies and Damselflies.

Dragonfly is a four-winged primitive flier. Wings twist and turn fast. The flier

has a low neurogenic frequency of 30–40 Hz. Dragonflies have a long distinct

abdomen. They are common good fliers. Metamorphosis is relatively simple

(Hemi-metabolous).

Thysanoptera

Thrips are tiny, slender insects having strap-like forewings and hindwings with long

fringes of hair, called fringed wings (Fig. 5.6). Wing lamina is usually reduced in

size with long hair or spine veins are absent. These insects literally swim through the

air as though it is a viscous medium. It is a serious agricultural pest. Metamorphosis

is simple. Thripidae is the largest injurious family for agricultural crops.

Example: Thrips.