Plastron (biology)

A plastron ( m. Or n. ), Also known as incompressible gas gill , is a film of air that forms on the surface of the body of aquatic insects . This film is held by specially designed outer surfaces of the body or by fine, water-repellent hair on the body surface. The hydrophobic structures have a slight kink at the top. This creates a surface tension that prevents the air from being displaced by the water. The gas gill receives the air supply either on the surface of the water or by diffusion from the surrounding water. Plastron wearers do not necessarily have to come to the surface of the water to breathe, but often remain under water for their entire life. Here lies the main difference to the physical gill , which always needs a supply of air from the surface.

The plastron can be found in various groups of insects, such as ground bugs (Aphelocheiridae), hook beetles ( Dryopidae and Elmidae , yoke beetles ( Scirtidae ) and various weevils , but not in spiders of the water spider species (Argyroneta aquatica).

A special form of the plastron is the spiracular gill, which occurs in various aquatic two-winged pupae (for example, the eyelid gnats ( Blephariceridae), the flies (Tipulidae) or the black flies (Simuliidae)). Here the air-retaining structure is formed by a lamella pattern.

The dolls of water parasitic wasp ( Agriotypus armatus ) live in the quiver of a caddis pupa ( Trichoptera ). They are surrounded by air in their cocoons and have a tongue-shaped, air-filled breathing strap (approx. 10 to 30 mm long) that floats in the water and is used for plastron breathing.

literature

HE Hinton: Spiracular gills. In: Adv Insect Physiol. 5, 1968, pp. 65-161, 1968.

HE Hinton: Plastron respiration in bugs and beetles. In: J Insect Physiol. 22, 1976, pp. 1529-1550.

HE Hinton: The fine structure of the pupal plastron of Simuliid flies. In: J Insect Physiol. 22, 1976, pp. 1061-1070.

B. Messner, J. Adis: Functional morphological investigations on the plastron structures of arthropods. In: Verh Westd Entom Day 1993. Düsseldorf 1994.

PJ Mill: Respiration: aquatic insects. In: M. Rockstein (Ed.): The Physiology of Insecta. Vol VI, New York / London 1974, pp. 403-467.

H. Rahn, CV Paginelli: Gas exchange in gas gills of diving insects. In: Resp Physiol. 5, 1968, pp. 145-164.

W. Wichard, W. Arens, G. Eisenbeis: Atlas for the biology of water insects. Stuttgart 1994.

Individual evidence

↑ Wesley Oliveira de Sousa, Germano Henrique Rosado-Neto, Marinêz Isaac Marques: Functionality of the plastron in adults of Neochetina eichhorniae Warner (Coleoptera, Curculionidae): aspects of the integument coating and submersion laboratory experiments. In: Revista Brasileira de Entomologia. 56 (3), pp. 347-353. (download)
↑ Hans Thiele: Water spider (Argyroneta aquatica), breathing according to the principle of the physical gill.
↑ H. Bürgis: The parasitic wasp Agriotypus armatus, a caddis fly parasite . In: Nature and Museum . tape 123 , no. 5 . Frankfurt a. M. 1993, p. 140-148 .

[1] Wesley Oliveira de Sousa, Germano Henrique Rosado-Neto, Marinêz Isaac Marques: Functionality of the plastron in adults of Neochetina eichhorniae Warner (Coleoptera, Curculionidae): aspects of the integument coating and submersion laboratory experiments. In: Revista Brasileira de Entomologia. 56 (3), pp. 347-353. (download)

[2] Hans Thiele: Water spider (Argyroneta aquatica), breathing according to the principle of the physical gill.

[3] H. Bürgis: The parasitic wasp Agriotypus armatus, a caddis fly parasite . In: Nature and Museum . tape 123 , no. 5 . Frankfurt a. M. 1993, p. 140-148 .