Turtle shell#Plastron

The plastron ( m. or AD ), also known as non-compressible gas gill, is a film of air forms on the Körperöberfläche of aquatic insects. Is held by this film specially designed exterior surfaces of the body or by fine, water-repellent hairs on the body surface. The hydrophobic structures have a slight bend at the tip. In this way, a surface tension is formed, which prevents a displacement of the air by the water. The air supply gets the gas gill either at the surface or by diffusion from the surrounding water. Plastron carrier so do not necessarily come to the surface, but often remain throughout life under water to breathe. Here lies the main difference between the physical gill, which always requires an air supply from the surface.

To find the plastron is in different insect groups, such as the basic bugs ( Aphelocheiridae ), the hook beetles ( Dryopidae and Elmidae, the Jochkäfern ( Scirtidae ) and various weevils, but not spinning the way water spider ( Argyroneta aquatica ). A special form of the plastron forms the Spirakulumkieme which at various aquatic Diptera dolls occurs ( for example, in the Lidmücken ( Blephariceridae ), the crane flies ( Tipulidae ) or the blackflies ( Simuliidae ). Here, the air retaining structure is formed by a lamellar pattern.

652721
de