60

N. Chari et al.

Fig. 5.3 Termites

Isoptera

These are social insects living in large colonies. They are small to medium sized,

pale coloured social insects living underground. In macropterous forms, two pairs of

wings are present which are similar in size, shape and venation (Fig. 5.3). Venation

is simple with few cross-veins. Wings are shedding type. Wings are present only

in Macropterous forms. Termites are poor fliers and live inside the wood and soil

(subterranean). Termite mounds are known in India and Africa. The life history of

termites is highly complicated.

Examples: Termites and White Ants.

Ephemeroptera

The wings are membranous, delicate with extensive venation and are held upright

like those of a butterfly (Fig. 5.4). The wings have many veins and cross-veins.

Forewings are large and triangular. Hindwings are smaller and fan-shaped. The

second segment of the thorax, which bears the forewings, is enlarged for accommo-

dating the main flight muscles. Simple and hemi-metabolous type of metamorphosis

is found in mayflies and they have a very short life.

Fig. 5.4 Mayfly