In entomology , the abdomen of an arthropod is called the abdomen . The abdomen joins the thorax . It contains the excretory, sexual and part of the digestive organs including the anus. The abdomen consists of several segments , in insects, for example, from 6 (in springtails ) to 11 (in leg masters and many flying insects , especially in their larvae ), as well as a dorsal segment ( telson ), which is not considered a full segment. Usually the maximum number of (11 + 1) segments is found in insects in the embryonic stage. Only then is it reduced accordingly. With the leg tinkerers, however, the “full” number of segments is only formed during the larval stages. With the springtails it is never reached.
A special characteristic of a segment of the abdomen is the petiolus ("small stalk", "small stalk" or "abdomen stalk").