How do Insects Breath - Spiracles!

Spiracle

Spiracles are openings on the surface of some animals, which usually lead to respiratory systems.

The spiracle is a small hole behind each eye that opens to the
mouth in some fish. In the primitive jawless fish the first gill opening immediately behind the mouth is essentially similar to the other gill opening.

Insects and some more derived spiders have spiracles on their exoskeletons to allow air to enter the trachea. In the respiratory system of insects, the tracheal tubes primarily deliver oxygen directly into the animals' tissues. The spiracles can be opened and closed in an efficient manner to reduce water loss. 


Air enters the insect's body through valve-like openings in the exoskeleton. These openings (called spiracles) are located laterally along the thorax and abdomen of most insects—usually one pair of spiracles per body segment

How do insects breathe?

Instead of lungs, insects breathe with a network of tiny tubes called tracheae. Air enters the tubes through a row of holes in the body walls called spiracles. Since the biggest bugs have the longest tracheae, they should need the most oxygen to be able to breathe.

Many water-dwelling insects have tracheal gills, which are layered extensions of their bodies that enable them to take more oxygen from the water. These gills are most often located on the abdomen, but in some insects, they are found in odd and unexpected places.