Exuvia

The exuvia (also exuvia from Latin exuviae, stored ( animal ) skin ',' Shirt ',' empty shell ') is the shedding of ( ecdysis ) shed skin of molting animals ( Ecdysozoa ) and reptiles ( Reptilia ).

The exuvia is usually exclusively from chitinisierter or calloused cuticle and sometimes also bears cuticular organs such as scales or bristles. Exuviae are mainly found in arthropods ( Arthropoda ) such as insects, arachnids and crustaceans, but also in the lower terrestrial vertebrates, such as snakes (as snake shirt) and lizards. The snake shirt is made of usually in one piece with the inside to the outside stripped old horn (cell ) layer (stratum corneum), the outermost layer consisting of dead cells of the epidermis (outer skin). In connection with the term reptiles Exuvie is however rarely used.

The resulting arthropod shedding of preparation gap between the old and newly emerging cuticle is called Exuvialraum. In this the animal emits a predominantly of chitinases and proteases existing secretion ( exuvial fluid ), which dissolves the old endocuticle from the inside.

In trilobites, horseshoe crabs and exuviae Seeskorpionen also form important fossils, because it is not about the animals themselves, but by the many growth-related moults, usually to their shed skin for most discovered fossils of these groups of animals.